88 results on '"Doxazosin Mesylate"'
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2. Mechanical, optical, and physicochemical properties of HPMC-based doxazosin mesylate orodispersible films
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Pamela Coradi da Silva, Larissa Aroca Colucci, Larissa Lea da Silva, Celso Molina, Marcelo Dutra Duque, and Leticia Norma Carpentieri Rodrigues
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Orodispersible films ,Design of experiments ,Doxazosin mesylate ,FTIR ,Mechanical properties ,Desirability function ,Pharmacy and materia medica ,RS1-441 - Abstract
Abstract In this study, orodispersible films formed from hydroxypropyl methylcellulose (HPMC) E6 (2, 2.5, and 3%) and plasticizers ((glycerin (Gly), propylene glycol (PP), or polyethylene glycol (PEG)), containing doxazosin mesylate, were prepared by the solvent casting method and characterized. Design of experiments (DoE) was used as a statistical tool to facilitate the interpretation of the experimental data and allow the identification of optimal levels of factors for maximum formulation performance. Differential scanning calorimetry (DSC) curves and X-ray powder diffraction (XRPD) diffractograms showed doxazosin mesylate amorphization, probably due to complexation with the polymer (HPMC E6), and the glass transition temperature of the polymer was reduced by adding a plasticizer. Fourier transformed infrared (FTIR) spectroscopy results showed that the chemical structure of doxazosin mesylate was preserved when introduced into the polymer matrix, and the plasticizers, glycerin and PEG, affected the polymer matrix with high intensity. The addition of plasticizers increased the elongation at break and adhesiveness (Gly > PEG > PP), confirming the greater plasticizer effect of Gly observed in DSC and FTIR studies. Greater transparency was observed for the orodispersible films prepared using PP. The addition of citric acid as a pH modifier was fundamental for the release of doxazosin mesylate, and the desirability formulation had a release profile similar to that of the reference product. more...
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- 2023
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Catalog
3. Determination of antihypertensive drugs irbesartan and doxazosin mesylate in healthcare products and urine samples using surface-enhanced Raman scattering.
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Ding, Yanru, Zhang, Nan, Zhao, Junqi, Lv, Haiyang, Wang, Xu, Zhao, Bing, and Tian, Yuan
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SERS spectroscopy , *ANTIHYPERTENSIVE agents , *IRBESARTAN , *DRUG tablets , *DENSITY functional theory - Abstract
In this paper, a surface-enhanced Raman scattering (SERS) strategy was constructed for the determination of antihypertensive drugs irbesartan (IRB) and doxazosin mesylate (DOX). β-Cyclodextrin-capped silver nanoparticles (CD-AgNPs) are employed as SERS-active substrate. The introduction of β-CD with hydrophobic cavity can capture drug molecules to form host–guest complex, making the drug molecules closer to the electromagnetic enhancement field of the AgNPs, thereby enhancing the SERS signal of drug molecules with low Raman cross-section. The vibrational modes of IRB and DOX are assigned by density functional theory calculations. The linear response from 3.0 × 10−7 to 1.0 × 10−5 mol L−1 for IRB and 3.0 × 10−7 to 2.0 × 10−5 mol L−1 for DOX and low limits of detection (LOD) 7.5 × 10−8 mol L−1 for IRB and 8.6 × 10−8 mol L−1 for DOX can be achieved. Meanwhile, this SERS approach can be applicable to determine IRB and DOX in commercial drug tablets, healthcare products, and human urine samples with recoveries of 90.8–115.7% and 90.0–113.5%, respectively, with relative standard deviation (RSD) less than 4.5%. This designed SERS strategy enables for the rapid determination of IRB and DOX in drug quality monitoring and illegal additives in healthcare products as well as clinical applications. [ABSTRACT FROM AUTHOR] more...
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- 2022
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4. 甲磺酸多沙唑嗪在女性膀胱过度活动症的临床应用.
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杨晓倩, 张钰泉, 王辉涛, 杨童欣, 陈韬, 翁雨亭, and 方克伟
- Abstract
Objective To study the clinical therapeutic effect of doxazosin mesylate on female patients with overactive bladder (OAB) complicated with micturition symptoms. Methods A retrospective analysis was made of 68 female patients who were diagnosed with OAB and complicated with micturition symptoms in the Outpatient Department of Urology of the Second Affiliated Hospital of Kunming Medical University from June to December 2021 due to lower urinary tract symptoms (LUTS). Among them,36 cases were treated with doxazosin mesylate combined with solinacin succinate tablets as the treatment group; 32 cases were treated with solinacin succinate tablets as the control group. After 12 weeks of the treatment,the symptoms before and after the treatment were compared using American Urological Association symptom score (AUAss), overactive bladder symptom score (OABSS) and quality of life (QOL) score. Results After 12 weeks of the treatment,the scores of OABSS,AUAss and QOL in the treatment group and the control group were significantly improved compared with those before the treatment (P < 0.05). There was significant difference in AUAss between the treatment group and the control group (P < 0.05). Conclusion Doxazosin mesylate combined with sorinaxin succinate tablets can improve lower urinary tract symptoms and quality of life in female patients with OAB complicated with micturition symptoms. [ABSTRACT FROM AUTHOR] more...
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- 2022
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5. Aggregation of Gold Nanoparticles for Spectrophotometric Determination of Bisoprolol Hemifumarate, Buspirone HCl and Doxazosin Mesylate
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Magda Mohamed Ayad, Hisham Ezzat Abdellatef, Mervat Mohamed Hosny, and Naglaa Abdel-Sattar Kabil
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gold nanoparticles ,bisoprolol hemifumarate ,buspirone hcl ,doxazosin mesylate ,Biology (General) ,QH301-705.5 ,Medicine - Abstract
A simple, rapid and sensitive spectrophotometric method was developed for determination of bisoprolol hemifumarate, buspirone HCl and doxazosin mesylate in pure form and in pharmaceutical formulations. The method was based on aggregation of synthesized gold nanoparticles (Au NPs). Gold nanoparticles showed an absorption band at 520 nm. Upon interaction with the cited drugs, the band at 520 nm disappeared with formation of a new red shifted band at 616, 656 and 670 nm for doxazosin mesylate, bisoprolol hemifumarate and buspirone HCl, respectively. Different experimental factors were optimized for higher sensitivity. The calibration curves were linear with concentrations of 3-14, 0.1-1.2 and 0.2-1.0 μg/mL for bisoprolol hemifumarate, buspirone HCl and doxazosin mesylate, respectively. The method was applied successfully to determine the studied drugs in minor concentrations in pure form and in their pharmaceutical dosage forms. more...
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- 2019
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6. Stability Indicating UPLC Method for Determination of Related Substances in Doxazosin mesylate
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Sushma, Bulusu Lakshmi, Madhusudhan, Gutta, and Jayashree, Anireddy
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- 2017
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7. Chitosan-TPP nanoparticles stabilized by poloxamer for controlling the release and enhancing the bioavailability of doxazosin mesylate: in vitro, and in vivo evaluation.
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Aljaeid, Bader M., El-Say, Khalid M., and Hosny, Khaled M.
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BIOAVAILABILITY ,BENIGN prostatic hyperplasia ,PATIENT compliance ,SODIUM tripolyphosphate ,ZETA potential ,NANOPARTICLES - Abstract
Objective: Control the release and enhance the bioavailability of chitosan-doxazosin mesylate nanoparticles (DM-NPs). Significance: Improve DM bioavailability for the treatment of benign prostatic hyperplasia and hypertension. Methods: Plackett–Burman design was utilized to screen the variables affecting the quality of DM-NPs prepared by ionic gelation method. The investigated variables were initial drug load (X
1 ), chitosan percentage (X2 ), tripolyphosphate sodium (TPP) percentage (X3 ), poloxamer percentage (X4 ), homogenization speed (X5 ), homogenization time (X6 ) and TPP addition rate (X7 ). The prepared DM-loaded NPs have been fully evaluated for particle size (Y1 ), Zeta potential (Y2 ), production yield (Y3 ), entrapment efficiency (Y4 ), loading capacity (Y5 ), initial burst (Y6 ), and cumulative drug release (Y7 ). Finally, DM pharmacokinetic has been investigated on healthy albino male rabbits by means of non-compartmental analysis. Results: The combination of variables showed variability of Y1 , Y2 , and Y3 equal to 122–710 nm, 3.49–23.63 mV, and 47.31–92.96%, respectively. While Y4 and Y5 , reached 99.87%, and 8.53%, respectively. The prepared NPs revealed that X2 , X3 , and X4 are the variables that play the important role in controlling the release behavior of DM from the NPs. The in vivo pharmacokinetic results indicated the enhancement in bioavailability of DM by 7 folds compared to drug suspension and the mean residence time prolonged to 23.72 h compared to 4.7 h of drug suspension. Conclusion: The study proved that controlling the release of DM from NPs enhance its bioavailability and improve the compliance of patients with hypertension or benign prostatic hyperplasia. [ABSTRACT FROM AUTHOR] more...- Published
- 2019
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8. A Rapid and Sensitive Reversed Phase Liquid Chromatography-Tandem Mass Spectrometry Method For Quantification Of Doxazosin Mesylate In Human Plasma Using Doxazosin Mesylate D8 As Internal Standard.
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Kapri, Anandi, Gupta, Nitin, and Raj, Garima
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LIQUID chromatography-mass spectrometry ,TANDEM mass spectrometry ,HIGH performance liquid chromatography ,BUTYL methyl ether ,LIQUID-liquid extraction ,REVERSE phase liquid chromatography - Abstract
A simple, accurate, precise and specific high performance liquid chromatography mass spectrometric method for the estimation of doxazosin in human plasma (K2EDTA), using doxazosin D8 as an internal standard was developed and validated. The samples are prepared by liquid-liquid extraction method by using tetra butyl methyl ether, followed by freezing and evaporation of the organic solvent. The remaining dry residue is redissolved in mobile phase and analyzed by LC-MS-MS with positive electro spray ionization using the multi reaction monitoring mode. An unisol C18 (150 X 4.6) mm, 5 μm, 100 A° column, a mobile phase composed of acetonitrile and 0.05 % ammonia solution in HPLC grade water with isocratic elution, and a flow rate of 1.000 mL/minute with split ratio 1:1 and the column oven temperature was set 40±2°C. The elution time for doxazosin and internal standard were 2 min. All the parameters were maintained for the study. This method is validated for 0.301 ng/mL to 75.179 ng/mL concentration range. The method is applied for doxazosin plasma levels following single administration of doxazosin mesylate tablets to human in the fed state. [ABSTRACT FROM AUTHOR] more...
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- 2019
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9. Aggregation of Gold Nanoparticles for Spectrophotometric Determination of Bisoprolol Hemifumarate, Buspirone HCl and Doxazosin Mesylate.
- Author
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Ayad, Magda Mohamed, Abdellatef, Hisham Ezzat, Hosny, Mervat Mohamed, and Kabil, Naglaa Abdel-Sattar
- Subjects
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GOLD nanoparticles , *BISOPROLOL , *DOSAGE forms of drugs , *BUSPIRONE , *REDSHIFT , *DRUG interactions - Abstract
A simple, rapid and sensitive spectrophotometric method was developed for determination of bisoprolol hemifumarate, buspirone HCl and doxazosin mesylate in pure form and in pharmaceutical formulations. The method was based on aggregation of synthesized gold nanoparticles (Au NPs). Gold nanoparticles showed an absorption band at 520 nm. Upon interaction with the cited drugs, the band at 520 nm disappeared with formation of a new red shifted band at 616, 656 and 670 nm for doxazosin mesylate, bisoprolol hemifumarate and buspirone HCl, respectively. Different experimental factors were optimized for higher sensitivity. The calibration curves were linear with concentrations of 3-14, 0.1-1.2 and 0.2-1.0 μg/mL for bisoprolol hemifumarate, buspirone HCl and doxazosin mesylate, respectively. The method was applied successfully to determine the studied drugs in minor concentrations in pure form and in their pharmaceutical dosage forms. [ABSTRACT FROM AUTHOR] more...
- Published
- 2019
- Full Text
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10. New Approach for Administration of Doxazosin Mesylate: Comparative Study between Liquid and Solid Self-nanoemulsifying Drug Delivery Systems
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Gehan F. Balata, Noura G. Eissa, Hanan M. El Nahas, and Al Zahraa G. Al Ashmawy
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PEG 400 ,Oleic acid ,chemistry.chemical_compound ,Aqueous solution ,Chemistry ,Drug delivery ,Zeta potential ,General Pharmacology, Toxicology and Pharmaceutics ,Solubility ,Dissolution ,Doxazosin Mesylate ,Nuclear chemistry - Abstract
Self-nanoemulsifying drug delivery systems (SNEDDS) in both liquid and solid forms were suggested to improve water solubility of Doxazosin mesylate (DOX) a poorly water- soluble antihypertensive drug. Oleic acid: Smix (1:9 w/w) and Tween 80: co-surfactant mixture (Ethanol and PEG 400) (1:1, 2:1, 3:1 and 4:1) were chosen to prepare a liquid and solid forms of SNEDDS according to their solubility. TEM images revealed change in the crystalline nature of DOX into uniform particles with smooth surface. Characterization studies revealed droplet size ranges from 79.80±14.39 to 273.10±4.17 nm, zeta potential ranges from -5.57±0.10 to -21.13±0.46 mV and dissolution enhancement of more than two folds with more favorable properties for the solid forms. FTIR demonstrated significant physical changes in DOX crystalline structure. In conclusion, the solid SNEDDS containing oleic acid: Smix (1:9 w/w) and Tween 80: co-surfactant mixture (3:1 w/w) and adsorbent mixture of Avicel 101 and Aerosil 200 (40:1 w/w) might be a promising formula for better management of hypertension with expected shelf stability. more...
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- 2021
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11. Development and Validation of a Reversed-Phase HPLC Method for Simultaneous Determination of Doxazosin Mesylate and Finasteride.
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KROTZ, DILLON and MENGESHA, ABEBE E.
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HIGH performance liquid chromatography ,DOXAZOSIN ,FINASTERIDE ,PHARMACEUTICAL powders ,ACETIC acid - Abstract
A reversed-phase high-performance liquid chromatographic (RP-HPLC) method was developed and validated for the simultaneous determination of doxazosin mesylate (DOX) and finasteride (FIN) in bulk powders and pharmaceutical formulations. The compounds were separated on a Pinnacle II C18 column (250 × 4.6 mm i.d.; particle size, 5 μm) with an isocratic mobile phase at a flow rate of 1.0 mL min
-1 . The mobile phase was a mixture of 25 mM ammonium acetate and acetonitrile in the ratio of 50:50 %v/v. The pH of the buffer was adjusted to 4.0 ± 0.05 with glacial acetic acid. The detection was performed at 230 nm. The total chromatographic analysis time per sample was 15 min with DOX and FIN eluting at 3.9 and 7.2 min, respectively. The accuracy, precision, specificity, linearity, and sensitivity of the method were validated according to the International Conference on Harmonization (ICH) guidelines. The calibration plots were linear (r2 > 0.999) over the concentration range 24.25-291.0 μg mL-1 and 122.5- 1470.0 μg mL-1 for DOX and FIN, respectively. The method was used for the simultaneous determination of DOX and FIN in capsules. [ABSTRACT FROM AUTHOR] more...- Published
- 2017
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12. Improved Hypertension by Investigating Circadian Rhythm of Blood Pressure
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Miwako Nakanishi, Shinji Nagahiro, Osami Watanabe, Hiroshi Bando, and Tadao Shimamura
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Amlodipine besilate ,medicine.medical_specialty ,Circadian Rhythm of Blood Pressure ,medicine.drug_class ,business.industry ,030204 cardiovascular system & hematology ,Chemical company ,Doxazosin Mesylate ,03 medical and health sciences ,0302 clinical medicine ,Blood pressure ,Hinohara-ism ,Internal medicine ,Hypertension ,Antihypertensive drug ,medicine ,Cardiology ,030212 general & internal medicine ,Circadian rhythm ,Amlodipine ,business ,Morning ,medicine.drug - Abstract
Case: The case is 86-year-old male hypertensive patient with anti-hypertensive drug for 5 years. He has been provided Amlodipine besilate 5mg at 0800h and doxazosin mesylate 2mg at 2300h for long. In June 2020, he noticed unstable fluctuation of Blood Pressure (BP) during morning, afternoon and night. Results: Then, he checked the circadian rhythm of BP, which showed higher BP in early morning, decreasing BP 0800-1000h, minimum BP during 1000-1400h, increasing BP during 1400-1800h and stable BP during 1800-2400h. Due to the result, he changed to take amlodipine at 2300h. Consequently, his BP gradually became stable during 24 hours after 2 weeks. Discussion: Some factors may exist for contributing improved BP fluctuation. They include a) pathophysiological characteristics of BP circadian rhythm, b) effective time for anti-hypertensive drug, c) accuracy of the obtained BP data and d) the social and psychological reliability of the patient. Regarding d) he was engaged in research and development work as a senior researcher at a chemical company. He has been also a member of New Elderly Association (NEA), which was established by Shigeaki Hinohara. He lives on the philosophy of Hinohara-ism for long, associated with stable mind and body. more...
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- 2021
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13. Linear pharmacokinetics of doxazosin in healthy subjects
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Jaafar J. Ibraheem, Duaa J. Al-Tamimi, Mays E. Alani, and Afaq M. Ammoo
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Drug ,medicine.medical_specialty ,business.industry ,media_common.quotation_subject ,Healthy subjects ,Cmax ,Urology ,urologic and male genital diseases ,Essential hypertension ,medicine.disease ,Doxazosin Mesylate ,Pharmacokinetics ,medicine ,Doxazosin ,Dosing ,General Pharmacology, Toxicology and Pharmaceutics ,business ,media_common ,medicine.drug - Abstract
Doxazosin is used for treating symptoms of benign prostatic hyperplasia (BPH). Besides, it is also prescribed for patients with mild to moderate essential hypertension. The object of the current study was to assess the linearity in the pharmacokinetics of doxazosin after administration of doxazosin as a single dose tablet containing 2, 4 and 8 mg doxazosin mesylate. Thirty Iraqi healthy male adult subjects were given 2, 4 and 8 mg doxazosin mesylate tablet in a randomized, cross-over, open-label, fasting, three-period, three-sequence design separated by one week wash out the interval between dosing. Serial blood samples were obtained from each subject before drug intake (zero time) and then at 0.33, 0.67, 1.0, 1.33, 1.67, 2.0, 2.5, 3.0, 4.0, 6.0, 8.0, 12.0, 24.0, 36, 48, 60, and eventually at 72 hours after dosing. The pharmacokinetic parameters Cmax, AUC0–t, AUC0–∞, Tmax and Thalf were determined from plasma concentration-time data of the drug by non-compartmental analysis. Statistical analysis of doxazosin pharmacokinetic parameters obtained after administration of the investigated dose ranges 2-8 mg demonstrated linear pharmacokinetics. more...
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- 2020
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14. Extractive spectrophotometric determination of some α-adrenergic-antagonists in pure forms and in pharmaceutical formulations
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El Sheikh Ragaa, Esmail Nahla S., Gouda Ayman A., and Basset Walid Abdel
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doxazosin mesylate ,terazosin ,alfuzosine HCl ,spectrophotometry ,ion pair complex ,acid dyes ,pharmaceutical formulations ,Chemical engineering ,TP155-156 ,Chemical industries ,HD9650-9663 - Abstract
A simple, rapid, and extractive spectrophotometric methods was developed for the determination of some postsynaptic α-1 adrenoreceptor antagonist; doxazosin mesylate (DOX), terazosin (TRZ) and alfuzosine HCl (ALF) in pure forms and pharmaceutical formulations. The developed methods are based on the formation of yellow colored chloroform ion-pair complexes between the basic nitrogen of the drugs and dyes, namely; bromocresol green (BCG), bromothymol blue (BTB), methyl orange (MO) and alizarine red S (ARS), in acidic buffer of pH range (3.0-5.0). The formed complexes were extracted with chloroform or dichloromethane and measured at 418, 414, 425 and 426 nm for DOX and at 419, 415, 425 and 428 for TRZ and at 418, 412, 421 and 427 nm for ALF using BCG, BTB, MO and ARS, respectively. The analytical parameters and their effects on the reported systems are investigated. Beer’s law was obeyed in the range 1.0-130 μg mL−1 with correlation coefficient (n = 6) ≥ 0.9991. The molar absorpitivity, Sandell sensitivity, detection and quantification limits were also calculated. The composition of the ion associates was found 1:1 by Job’s method. The proposed methods have been applied successfully for the analysis of the studied drugs in pure forms and in pharmaceutical formulations with percentage recoveries ranges from 99.18-100.61. The results of analysis were validated statistically. The results were in good agreement and compared with those obtained with reported methods. more...
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- 2012
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15. A Rapid and Sensitive Reversed Phase Liquid Chromatography-Tandem Mass Spectrometry Method For Quantification Of Doxazosin Mesylate In Human Plasma Using Doxazosin Mesylate D8 As Internal Standard
- Author
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Anandi Kapri, Garima Raj, and Nitin Gupta
- Subjects
Chromatography ,010304 chemical physics ,Chemistry ,010401 analytical chemistry ,Reversed-phase chromatography ,urologic and male genital diseases ,Tandem mass spectrometry ,01 natural sciences ,Mass spectrometric ,High-performance liquid chromatography ,Doxazosin Mesylate ,0104 chemical sciences ,Human plasma ,Liquid–liquid extraction ,0103 physical sciences ,Doxazosin ,medicine ,Earth-Surface Processes ,medicine.drug - Abstract
A simple, accurate, precise and specific high performance liquid chromatography mass spectrometric method for the estimation of doxazosin in human plasma (K2EDTA), using doxazosin D8 as an internal... more...
- Published
- 2019
- Full Text
- View/download PDF
16. Chitosan-TPP nanoparticles stabilized by poloxamer for controlling the release and enhancing the bioavailability of doxazosin mesylate: in vitro, and in vivo evaluation
- Author
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Khaled M. Hosny, Bader M Aljaeid, and Khalid M. El-Say
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Pharmacology ,Mesylate ,Organic Chemistry ,Pharmaceutical Science ,02 engineering and technology ,Poloxamer ,021001 nanoscience & nanotechnology ,030226 pharmacology & pharmacy ,Doxazosin Mesylate ,Bioavailability ,Chitosan ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,chemistry ,Pharmacokinetics ,In vivo ,Drug Discovery ,0210 nano-technology ,Homogenization (biology) - Abstract
Objective: Control the release and enhance the bioavailability of chitosan-doxazosin mesylate nanoparticles (DM-NPs). Significance: Improve DM bioavailability for the treatment of benign prostatic hyperplasia and hypertension. Methods: Plackett-Burman design was utilized to screen the variables affecting the quality of DM-NPs prepared by ionic gelation method. The investigated variables were initial drug load (X1), chitosan percentage (X2), tripolyphosphate sodium (TPP) percentage (X3), poloxamer percentage (X4), homogenization speed (X5), homogenization time (X6) and TPP addition rate (X7). The prepared DM-loaded NPs have been fully evaluated for particle size (Y1), Zeta potential (Y2), production yield (Y3), entrapment efficiency (Y4), loading capacity (Y5), initial burst (Y6), and cumulative drug release (Y7). Finally, DM pharmacokinetic has been investigated on healthy albino male rabbits by means of non-compartmental analysis. Results: The combination of variables showed variability of Y1, Y2, and Y3 equal to 122-710 nm, 3.49-23.63 mV, and 47.31-92.96%, respectively. While Y4 and Y5, reached 99.87%, and 8.53%, respectively. The prepared NPs revealed that X2, X3, and X4 are the variables that play the important role in controlling the release behavior of DM from the NPs. The in vivo pharmacokinetic results indicated the enhancement in bioavailability of DM by 7 folds compared to drug suspension and the mean residence time prolonged to 23.72 h compared to 4.7 h of drug suspension. Conclusion: The study proved that controlling the release of DM from NPs enhance its bioavailability and improve the compliance of patients with hypertension or benign prostatic hyperplasia. more...
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- 2019
- Full Text
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17. Doxazosin Free-Base Structure Determination and Its Equilibrium Solubility Compared to Polymorphic Doxazosin Mesylate Forms A and H
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Mayra Guerra, Edeilson V. Gonzaga, Marina G. Evangelista, Iara M. L. Rosa, Jéssica L. J. Vilaca, Olimpia Maria Martins Santos Viana, Sara S. Vieira, Antonio C. Doriguetto, and Mariana M. Figueiredo
- Subjects
Drug ,Hypertension treatment ,010405 organic chemistry ,Chemistry ,media_common.quotation_subject ,Free base ,General Chemistry ,Pharmacology ,urologic and male genital diseases ,010402 general chemistry ,Condensed Matter Physics ,Biopharmaceutics Classification System ,01 natural sciences ,Doxazosin Mesylate ,0104 chemical sciences ,Doxazosin ,medicine ,General Materials Science ,Solubility ,media_common ,medicine.drug - Abstract
Doxazosin mesylate (DM) is a class II drug in the Biopharmaceutics Classification System (BCS) that is used in several types of hypertension treatments. DM presents almost 20 different polymorphs d... more...
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- 2019
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18. Micellar enhanced spectrofluorimetric approach for nanogram detection of certain α1‐blocker drugs: Application in pharmaceutical preparations and human plasma
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Baher I. Salman, Mahmoud A. Omar, and Mohamed A. Hammad
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Terazosin Hydrochloride ,Bioanalysis ,Chromatography ,010401 analytical chemistry ,Biophysics ,010402 general chemistry ,01 natural sciences ,Doxazosin Mesylate ,Dosage form ,0104 chemical sciences ,chemistry.chemical_compound ,Terazosin ,chemistry ,Chemistry (miscellaneous) ,Stearate ,medicine ,Doxazosin ,Alfuzosin ,medicine.drug - Abstract
Alpha1-adrenergic-blocking drugs, namely; alfuzosin hydrochloride (ALF), doxazosin mesylate (DOX) and terazosin hydrochloride (TER) are effective as antihypertensive agents as well as in management of benign prostatic hypertrophy. In this study, a simple, very fast, highly sensitive and cheap technique was optimized for assay of these drugs in pure states and pharmaceutical tablets. The proposed method is dependent on enhancement of the native fluorescence of investigated drugs using the polyoxyethylene 50 stearate (POE50S) micellar system. The method showed excitation at 325, 340 and 250 nm for ALF, DOX and TER, respectively and an emission maxima at 382 nm. The fluorescence intensity-concentration charts of studied drugs were attained utilizing concentration ranges (2.0-60.0 ng mL-1 ) for DOX and (4.0-100.0 ng mL-1 ) for ALF and TER with quantitation limits 2.9, 1.6 and 2.5 ng mL-1 for ALF, DOX and TER, respectively. The suggested technique was approved according to International Council for Harmonisation (ICH) standards and the United States Food and Drug Administration (US FDA) bioanalytical method validation and has been effectively applied for assay of these medications in their dosage forms as well as for content uniformity test. The developed procedure was also efficiently applied for determination of these drugs in real human plasma with high accuracy. more...
- Published
- 2018
- Full Text
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19. pH-independent sustained release matrix tablet containing doxazosin mesylate: Effect of citric acid.
- Author
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Cha, Kwang-Ho, Tran, Thanh-Huyen, Kim, Min-Soo, Kim, Jeong-Soo, Park, Hee, Park, Junsung, Cho, Wonkyung, and Hwang, Sung-Joo
- Abstract
The aim of this study was to develop a pH-independent sustained release matrix tablets of doxazosin mesylate. The matrix tablets were prepared by direct compression technique using polyethylene oxide, sodium alginate and citric acid as a pH modifier. Formulations were evaluated for an in vitro drug release study, erosion study, and the microenvironmental pH was studied using the pH indicator methyl red. For formulations without citric acid, the extent and rate of drug release in simulated gastric fluid were much higher than those in simulated intestinal fluid. By adding the citric acid, the drug release rate in simulated intestinal fluid was increased, and microenvironmental pH values within the tablets were maintained at low pH during drug release. Furthermore, drug release from the matrix tablet containing 20% w/w citric acid was comparable to that from a commercial product, Cardura® XL, and a pHindependent release could be achieved. Therefore, the incorporation of citric acid as a pH modifier to Polyethylen oxide-sodium alginate matrix tablets effectively produced pHindependent doxazocin mesylate release profiles. [ABSTRACT FROM AUTHOR] more...
- Published
- 2010
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20. Matrix tablets based on carrageenans with dual controlled release of doxazosin mesylate
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Pavli, Matej, Vrečer, Franc, and Baumgartner, Saša
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- *
CONTROLLED release drugs , *DRUG tablets , *POLYSACCHARIDES , *DOXAZOSIN , *POLYELECTROLYTES , *PH effect , *HYDRODYNAMICS - Abstract
Abstract: The use of polymeric polyelectrolytes as matrix-forming agents is far from optimally or fully understood. Polyelectrolyte carrageenan (CARR) matrices loaded with oppositely charged active substance doxazosin mesylate (DM) were investigated according to their water-uptake/erosion properties, in situ complexation ability of CARR with DM, and the possibility to achieve dual drug release control. Interactions between different CARR types (ι-, κ-, and λ-) and DM were confirmed by differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and zeta potential measurements. Combination of water-uptake/erosion with in situ complexation prolonged DM release from CARR matrices for more than 24h. The rate order of drug release was in accordance with the number of ester sulfate moieties per disaccharide unit of CARRs (κ (1)>ι (2)>λ (3)). The higher the charge on the CARR backbone, the higher the number of interactions with DM and the slower the drug release. Low pH, more vigorous hydrodynamics, and higher ionic strength resulted in faster drug release. Based on zeta potential measurements of DM and CARRs, proposed influence of counterion condensation and its effect on screening polyelectrolyte–drug interactions was confirmed to lower in situ DM–CARR complexation. Dual drug release control from polyelectrolyte matrices by water-uptake/erosion and in situ complexation offers many new approaches for designing controlled-release systems. [ABSTRACT FROM AUTHOR] more...
- Published
- 2010
- Full Text
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21. Doxazosin mesylate affects localization of endothelin-1 in prostatic tissues.
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Wroński, Stanisław, Grzanka, Dariusz, Wiśniewska, Halina, Korenkiewicz, Jadwiga, and Marszałek, Andrzej
- Subjects
- *
ADRENERGIC alpha blockers , *EXOCRINE glands , *PRAZOSIN derivatives , *ANTICHOLESTEREMIC agents , *EPITHELIUM , *CILIA & ciliary motion , *HEALTH care rationing - Abstract
Introduction. Data suggest that not only alpha-adrenergic factors contribute to contractility of smooth muscles of the prostate. The authors determined the influence of doxazosin mesylate on localization of endothelin-1 in prostatic tissue in treated and non-treated patients. Material and methods. Seventy patients with symptoms of prostate enlargement: 40 patients preliminary treated with doxazosin mesylate and 30 non-treated patients. All underwent prostate biopsy due to elevated PSA level (mean 5.85 ng/ml). Specimens were H&E stained for histopathology which confirmed diagnosis of benign hyperplasia and immunohistochemically stained for ET-1 in epithelium and prostate stroma. Authors calculated ET-1 mean optical density ratios (epithelial ET-1/stromal ET-1) for treated and non-treated patients. Statistical analysis was performed. Ratios of ET-1 in epithelium and stroma of both groups differed statistically. Conclusions. Obtained data indicate that relocation of endothelin-1 from prostate epithelium to stroma is altered in the treated group in comparison with the non-treated group. Doxazosin mesylate might have an influence on ET-1 redistribution from the epithelial compartment to the non-epithelial environment. This could be an additional mechanism of action of alphaadrenergic blockers in BPH patients. [ABSTRACT FROM AUTHOR] more...
- Published
- 2010
22. LC–MS determination and relative bioavailability of doxazosin mesylate tablets in healthy Chinese male volunteers
- Author
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Ma, Ning, Liu, Wenying, Li, Huande, Chen, Benmei, Zhu, Yungui, Liu, Xiaolei, Wang, Feng, Xiang, Daxiong, and Zhang, Bikui
- Subjects
- *
ANTICHOLESTEREMIC agents , *DOXAZOSIN , *BLOOD plasma , *AMINOACETONITRILE - Abstract
Abstract: This study aims to develop a standard protocol for the relative bioavailability testing of doxazosin mesylate tablets. For this purpose, a simple rapid and selective LC–MS method using a single quadrupole mass spectrometer was developed and validated to determine the concentration of doxazosin mesylate in human plasma. Using this method, we carried out a study of relative bioavailability. N-Hexylane-tertiary butyl methyl ether (1:1, v/v) was used to extract doxazosin mesylate and terazosin (internal standard, I.S.) from an alkaline plasma sample. LC separation was performed on a Thermo Hypersil-Hypurity C18 (5μm, 150mm×2.1mm) using aqueous solution (20mmol/l ammonium acetate, pH 4.28), methanol and acetonitrile (55:10:35, v/v/v) as the mobile phase. The retention time of doxazosin and the internal standard was 2.7 and 1.8min, respectively. Quadrupole MS detection was done by monitoring at m/z 388 (M+1) corresponding to doxazosin mesylate and at m/z 452 (M+1) for I.S. The assay method described above showed acceptable precision, accuracy, linearity, stability, and specificity. The bioavailability of doxazosin mesylate was evaluated in 12 healthy Chinese male volunteers. The following pharmacokinetic parameters were elucidated after administering a single dose of 4mg doxazosin. The area under the plasma concentration versus time curve from time 0 to 72h (AUC0–72h) 743.4±149.5ngh/ml; peak plasma concentration (C max) 47.66ng/ml; time to C max (T max) 3.0±1.0h; and elimination half-life (t 1/2) 18–20h. The method was successfully used to determine the relative bioavailability of doxazosin mesylate. [Copyright &y& Elsevier] more...
- Published
- 2007
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23. Development and validation of a reversed-phase HPLC method for simultaneous determination of doxazosin mesylate and finasteride
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Dillon Krotz and Abebe Endale Mengesha
- Subjects
Chromatography ,030232 urology & nephrology ,General Chemistry ,Reversed-phase chromatography ,030226 pharmacology & pharmacy ,Doxazosin Mesylate ,03 medical and health sciences ,chemistry.chemical_compound ,Acetic acid ,0302 clinical medicine ,chemistry ,Phase (matter) ,Finasteride ,Particle size ,Acetonitrile ,Ammonium acetate - Abstract
A reversed-phase high-performance liquid chromatographic (RP-HPLC) method was developed and validated for the simultaneous determination of doxazosin mesylate (DOX) and finasteride (FIN) in bulk powders and pharmaceutical formulations. The compounds were separated on a Pinnacle II C18 column (250 × 4.6 mm i.d.; particle size, 5 μm) with an isocratic mobile phase at a flow rate of 1.0 mL min−1. The mobile phase was a mixture of 25 mM ammonium acetate and acetonitrile in the ratio of 50:50 %v/v. The pH of the buffer was adjusted to 4.0 ± 0.05 with glacial acetic acid. The detection was performed at 230 nm. The total chromatographic analysis time per sample was 15 min with DOX and FIN eluting at 3.9 and 7.2 min, respectively. The accuracy, precision, specificity, linearity, and sensitivity of the method were validated according to the International Conference on Harmonization (ICH) guidelines. The calibration plots were linear (r2 > 0.999) over the concentration range 24.25–291.0 μg mL−1 and 122.5–1470.0 μg ... more...
- Published
- 2017
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24. A COMPLETE NMR STUDY OF DOXAZOSIN CHARACTERIZATION
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Mariana Maier Gaelzer, Itamar Luís Gonçalves, Gabriel Oliveira de Azambuja, Christianne Gazzana Salbego, Vera Lucia Eifler-Lima, and CNPq
- Subjects
Stereochemistry ,Chemistry ,doxazosin ,urologic and male genital diseases ,signals assignment ,Doxazosin Mesylate ,nmr ,Doxazosin ,medicine ,Enantiomer ,Spectroscopy ,QD1-999 ,TP248.13-248.65 ,Heteronuclear single quantum coherence spectroscopy ,ft-ir ,Biotechnology ,medicine.drug - Abstract
Doxazosin is an important drug used for treating hypertension and prostatic hyperplasia. An enantiomeric mixture (R)/(S) doxazosin mesylate was complete characterized by NMR and additionally FT-IR spectroscopy techniques. Were performed different NMR experiments, such as APT, HSQC, and HMBC in order to confirm the NMR signals assignments. All the hydrogens and the most of carbons atoms were assigned. more...
- Published
- 2017
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25. Enantiomeric resolution of doxazosin mesylate and its process-related substances on polysaccharide chiral stationary phases
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Nageswara Rao, R., Nagaraju, D., and Narasa Raju, A.
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HIGH performance liquid chromatography , *ANTICHOLESTEREMIC agents , *ANTIHYPERTENSIVE agents , *CHROMATOGRAPHIC analysis - Abstract
Abstract: High-performance liquid chromatographic methods for separation of racemic doxazosin mesylate and its synthetic precursors on polysaccharide based stationary phases viz., amylose tris-(3,5-dimethylphenylcarbamate) (Chiralpak AD-H) and cellulose tris-(3,5-dimethylphenylcarbamate) (Chiralcel OD-H) were developed. The base line separation with R s >1.50 was obtained using a mobile phase containing n-hexane–alcohol–0.1% diethylamine (ethanol, 1-propanol and 2-propanol) in various proportions. The effect of concentration of the alcoholic modifiers on the resolution was studied. A good separation was achieved on amylose based Chiralpak AD-H column when compared with cellulose based Chiralcel OD-H. The effects of structural features of the solutes and solvents on discrimination between the enantiomers were examined. The detection was carried out at 240nm with UV detector while identification by polarimetric detector connected in series. The method was suitable not only for process development of doxazosin mesylate but also determination of enantiomeric purity of bulk drugs and pharmaceuticals. [Copyright &y& Elsevier] more...
- Published
- 2006
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26. Syntheses of molecularly imprinted polymers and their molecular recognition study for doxazosin mesylate
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Wang, Huai You, Jiang, Ji Gang, Ma, Li Ying, and Pang, Yan Ling
- Subjects
- *
POLYMERS , *ANTICHOLESTEREMIC agents , *ANTIHYPERTENSIVE agents , *IMPRINTED polymers - Abstract
Abstract: Molecular imprinted polymers (MIPs) (diameter is about 1.7μm) were prepared from methacrylic acid as the functional monomer and triallyl isocyanurate as the cross-linker in methanol solution using doxazosin mesylate as the template molecule and 2,2′-azobis-isobutyronitrile as the initiator. The effects of amount of the cross-linker, the ratio of template molecule and functional monomer, amount of solvent and amount of the radical initiator on the polymerization were examined. Release of the template was performed by continuous extraction with methanol containing 10% acetic acid. These MIPs showed specific binding affinity toward doxazosin mesylate and the imprinting mechanism is discussed. The principal advantage of the method is that the MIPs prepared can recognize doxazosin mesylate and the particles size can be controlled by the amount of initiator and the volume of methanol employed. [Copyright &y& Elsevier] more...
- Published
- 2005
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27. Polymorphism of doxazosin mesylate.
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Sohn, Young-Taek and Lee, Yoon-Hee
- Abstract
Nine polymorphic modifications of doxazosin mesylate have been obtained by recrystallization in organic solvents under variable conditions. Different polymorphs of doxazosin mesylate were characterized by powder X-ray crystallography diffractometry (PXRD), differential scanning calorimetry (DSC), and thermogravimetric analysis (TG). Transformation of Form 1 and Form 2 was not occurred in three relative humidities (0%, 51%, and 99%) at 20±0.5 for 30 days. [ABSTRACT FROM AUTHOR] more...
- Published
- 2005
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28. Protonation site and hydrogen bnoding in anhydrous and hydrated crystalline forms of doxazosin mesylate from powder data.
- Author
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Chernyshev, Vladimir V., Machon, Denis, Fitch, Andrew N., Zaitsev, Sergei A., Yatsenko, Alexandr V., Shmakov, Alexandr N., and Weber, Hans-Peter
- Subjects
- *
DOXAZOSIN , *CRYSTALS , *PROTON transfer reactions , *HYDROGEN bonding , *X-ray diffractometers , *SYNCHROTRONS , *ANTIHYPERTENSIVE agents - Abstract
The three-dimensional solid-state structures of two modifications of doxazosin mesylate C23H26N5O+5.CH3SO-3, 4-amino-2-[4-[(2,3-dihydro-1,4-benzodioxin-2-yl)carbonyl]piperazin-1yl]-6, 7-dimethoxyquinazoline methanesulfonate, a commonly used antihypertensive agent, have been determined by synchrotron X-ray powder diffraction. An anhydrous form (A) and a dihydrate form (dG) crystallize in monoclinic space groups. In both forms the doxazosin molecule is protonated at the N1 atom of the quinazoline bicycle. The N1 atom, and the amino H atoms and O atoms of the mesylate moieties are involved in three-dimensional hydrogen-bonding networks, while solvent water molecules and carboxamide O atoms are also incorporated in a hydrogen-bonding network in dG. [ABSTRACT FROM AUTHOR] more...
- Published
- 2003
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29. Stability-indicating methods for the determination of doxazosin mezylate and celecoxib
- Author
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Bebawy, L.I., Moustafa, A.A., and Abo-Talib, N.F.
- Subjects
- *
DOXAZOSIN , *METHANESULFONATES , *CELECOXIB - Abstract
Two stability-indicating methods were developed for the determination of doxazosin mesylate (I) and celecoxib (II) in the presence of their degradation products. The first method depends on the use of first derivative spectrophotometry (D1) at 256, 269 nm for (I) and (II), respectively. This method determines (I) and (II) in concentration ranges of 0.8–12 and 1–20 μg ml−1 with mean percentage accuracies of 99.21±0.88 and 99.59±1.67% for (I) and (II), respectively. The second method depends on the quantitative densitometric evaluation of thin-layer chromatography of (I) and (II) in the presence of their degradation products without any interference. Methylisobutyl ketone–glacial acetic acid–water (20:10:10) was used as a mobile phase for (I) and cyclohexane–dichloromethane–diethyleamine (50:40:10) for (II). The chromatograms were scanned at 248 and 253 nm for (I) and (II), respectively. This method determines (I) and (II) in concentration ranges of l–4 μg per spot for both drugs with mean percentage accuracies of 100.19±0.95 and 99.91±1.95% for (I) and (II), respectively. The suggested methods were used to determine doxazosin mesylate and celecoxib in bulk powder, laboratory-prepared mixtures and pharmaceutical dosage forms (cardura tablet and celebrex capsule). The results obtained by applying the proposed methods were statistically analysed and compared with those obtained by the reported methods. [Copyright &y& Elsevier] more...
- Published
- 2002
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30. Effects of doxazosin mesylate versus nifedipine on blood pressure variability in hypertensive patients: a randomized crossover study (SIMILAR)
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Yue Li, Yujiao Pan, Meijiao He, Guangzhong Liu, Jing Shi, Song Zhang, Hai Cang, Desen Liang, Yongtai Gong, Haiyu Zhang, and Wennan Wang
- Subjects
Adult ,Male ,medicine.medical_specialty ,Ambulatory blood pressure ,Adolescent ,Nifedipine ,Diastole ,Blood Pressure ,030204 cardiovascular system & hematology ,Assessment and Diagnosis ,Essential hypertension ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Internal medicine ,Internal Medicine ,Doxazosin ,medicine ,Humans ,030212 general & internal medicine ,Antihypertensive Agents ,Aged ,Advanced and Specialized Nursing ,Cross-Over Studies ,business.industry ,General Medicine ,Blood Pressure Monitoring, Ambulatory ,Middle Aged ,medicine.disease ,Calcium Channel Blockers ,Crossover study ,Doxazosin Mesylate ,Blood pressure ,Cardiology ,Female ,Essential Hypertension ,Cardiology and Cardiovascular Medicine ,business ,medicine.drug - Abstract
Blood pressure variability (BPV) is a powerful predictor of end-organ damage, cardiovascular events and mortality independently of the BP level. Calcium channel blockers may offer an advantage over other first-line antihypertensive drugs by preventing increased BPV. But the effect of alpha-receptor blockers on BPV in hypertensive patients is still unclear.In this crossover trial, 36 hypertensive patients were randomly assigned to two groups, receiving doxazosin mesylate gastrointestinal therapeutic system (GITS) (4 mg/day) or nifedipine GITS (30 mg/day) for 12 weeks, followed by a 2-week washout period then a 12-week crossover phase. At baseline and after 12-week treatment, 24-hour ambulatory BP monitoring was performed. BPV was evaluated through standard deviation (SD), coefficient of variation (CV), and average real variability (ARV) of systolic BP (SBP) and diastolic BP (DBP) during daytime, nighttime and over 24 hours.After 12-week treatment, both doxazosin and nifedipine significantly decreased SBP and DBP (P0.05), whereas no between-group differences were shown (P0.05). Systolic BPV (24-hour SD, CV, and ARV; daytime SD; nighttime SD and CV) and diastolic BPV (24-hour SD and ARV) were significantly lowered by nifedipine (P0.05); doxazosin resulted in significant reductions of systolic BPV (24-hour SD, CV and ARV; daytime SD; nighttime SD) and diastolic BPV (nighttime SD and CV) (P0.05). Doxazosin was revealed to be as effective as nifedipine for reducing BPV (P0.05) except for 24-hour SBP ARV.Doxazosin mesylate GITS had similar therapeutic effects on BP, BP SD, and BP CV lowering as nifedipine GITS in patients with mild-to-moderate essential hypertension. more...
- Published
- 2019
31. Fast disintegrating tablet of Doxazosin Mesylate nanosuspension: Preparation and characterization
- Author
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Gehan F. Balata, Noura G. Eissa, Hanan M. El Nahas, and Al Zahraa G. Al Ashmawy
- Subjects
Materials science ,Pharmaceutical Science ,02 engineering and technology ,Factorial experiment ,021001 nanoscience & nanotechnology ,Friability ,030226 pharmacology & pharmacy ,Doxazosin Mesylate ,Dosage form ,Bioavailability ,03 medical and health sciences ,0302 clinical medicine ,Differential scanning calorimetry ,Fourier transform infrared spectroscopy ,0210 nano-technology ,Dissolution ,Nuclear chemistry - Abstract
Doxazosin Mesylate (DOX) is an antihypertensive drug which possesses poor water solubility and hence low bioavailability. The study objective is to prepare DOX fast disintegrating tablets as a new dosage form for geriatric patients. First, 23 full factorial design using Polyvinyl pyrrolidone k 30, Poloxamer-407 and Sodium Lauryl Sulphate at low and high ratios were used for preparation of DOX nanosuspension as a trial to improve its dissolution properties. Nanosuspension formulations were characterized using Transmission electron microscopy, Differential scanning calorimetry and Fourier transform infrared spectroscopy. Then, the optimized formula was incorporated in fast disintegrating tablets using different superdisintegrants. The tablets were evaluated for hardness, thickness, friability percentage, diameter, weight variation, Wetting time, disintegration time and percentage dissolution after 10 min. A significant reduction (rapidly and efficiently) in mean arterial pressure of hypertensive rats was observed for DOX nanosuspension fast disintegrating tablet using Ac-Di-Sol as a superdisintegrant with 100% dissolution after 10 min. more...
- Published
- 2021
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32. Spectrophotometric determination of buspirone HCl and doxazosin mesylate using citrate-capped silver nanoparticles
- Author
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Magda Mohamed Ayad, Mervat M. Hosny, Hisham E. Abdellatef, and Naglaa Abdel-Sattar Kabil
- Subjects
chemistry.chemical_compound ,Materials science ,chemistry ,Calibration curve ,Absorption band ,Buspirone hcl ,Sodium citrate ,Industrial and Manufacturing Engineering ,Quantitative determination ,Doxazosin Mesylate ,Silver nanoparticle ,Nuclear chemistry - Abstract
A simple and rapid spectrophotometric method was developed for determination of buspirone HCl and doxazosin mesylate in bulk and pharmaceutical formulations. In this paper silver nanoparticles (Ag-NPs) were prepared chemically using sodium citrate as reducing and stabilising agent. Silver nanoparticles showed an absorption band at 420 nm. Aggregation of citrate stabilised silver nanoparticles (Ag NPs) were used for quantitative determination of the studied drugs with formation of a new red shifted band at 545, 690 nm for buspirone HCl and doxazosin mesylate respectively. Different experimental factors were optimised and the calibration curves were linear with concentrations of (0.10-0.60 μg/mL), (5.0-14.0 μg/mL) for buspirone HCl and doxazosin mesylate respectively. Validation of the analytical performance of the method was carefully investigated, and the results were satisfactory. more...
- Published
- 2021
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33. Aggregation of Gold Nanoparticles for Spectrophotometric Determination of Bisoprolol Hemifumarate, Buspirone HCl and Doxazosin Mesylate
- Author
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Hisham E. Abdellatef, Magda Mohamed Ayad, Mervat M. Hosny, and Naglaa Abdel-Sattar Kabil
- Subjects
Chemistry ,Colloidal gold ,Buspirone hcl ,Biomedical Engineering ,Bisoprolol Hemifumarate ,Doxazosin Mesylate ,Nuclear chemistry - Published
- 2019
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34. Preparation and characterization of controlled-release doxazosin mesylate pellets using a simple drug layering-aquacoating technique
- Author
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Ossama Y. Abdallah, Magda A. El-Massik, Hamdy Abdelkader, and Heba A. Hazzah
- Subjects
Materials science ,Chromatography ,Scanning electron microscope ,Pellets ,Pharmaceutical Science ,Pharmacology ,engineering.material ,Controlled release ,Doxazosin Mesylate ,Microcrystalline cellulose ,chemistry.chemical_compound ,chemistry ,Coating ,Pellet ,engineering ,Dispersion (chemistry) ,Pharmacology, Toxicology and Pharmaceutics (miscellaneous) - Abstract
Pellets are one of multiparticulate pharmaceutical forms and can offer numerous technical and biopharmaceutical advantages compared with single dose unit formulations, e.g. tablets and capsules. This study aimed at formulation of controlled-release pellets of doxazosin mesylate (DM), a widely used treatment for antihypertensive and benign prostatic hyperplasia. DM was loaded onto microcrystalline cellulose CELLETS® pellets using hydroalcoholic solution and alcoholic suspension layering techniques to achieve a minimum drug load of 4 mg DM/g pellets. DM-layered CELLETS were coated by Aquacoat dispersion (ready-made ethylcellulose dispersion) using a coating pan technique as a simple and widely utilized technique in pharmaceutical industry. Controlled-release DM-layered pellets showed a release profile comparable to the controlled-release commercial product Cardura® XL Tablet. Also, the mechanism of DM release from Aquacoat CELLETS was mathematically modeled and imaged by scanning electron microscopy to elucidate drug release mechanisms from the prepared pellet formulations. Accelerated stability studies of the prepared pellets were performed under stress conditions of 40 °C, and 75 % RH for 3 months. In conclusion, preparation of controlled-release DM-layered CELLETS® is feasible using a simple and conventional coating pan technology. more...
- Published
- 2013
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35. CONTROLLED-RELEASE TABLETS OF DOXAZOSIN MESYLATE AND PHENOXYBENZAMINE IN PREOPERATIVE PREPARATION AND BLOOD PRESSURE CONTROL FOR PHEOCHROMOCYTOMA PATIENTS
- Author
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Bin Liu, Xia Cao, and Xinquan Gu
- Subjects
Blood pressure control ,Pheochromocytoma ,Phenoxybenzamine ,business.industry ,Anesthesia ,medicine ,medicine.disease ,business ,Controlled release ,Doxazosin Mesylate ,medicine.drug - Published
- 2016
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- View/download PDF
36. Extractive spectrophotometric determination of some α-adrenergic-antagonists in pure forms and in pharmaceutical formulations
- Author
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Abdel Walid Basset, Sheikh Ragaa El, Ayman A. Gouda, and Nahla S. Esmail
- Subjects
General Chemical Engineering ,ion pair complex ,chemistry.chemical_compound ,Terazosin ,Spectrophotometry ,medicine ,Methyl orange ,spectrophotometry ,lcsh:Chemical engineering ,lcsh:HD9650-9663 ,Dichloromethane ,Chloroform ,Bromocresol green ,Chromatography ,medicine.diagnostic_test ,acid dyes ,Alfuzosine ,lcsh:TP155-156 ,chemistry ,alfuzosine HCl ,pharmaceutical formulations ,doxazosin mesylate ,α adrenergic ,terazosin ,medicine.drug ,lcsh:Chemical industries - Abstract
A simple, rapid, and extractive spectrophotometric methods was developed for the determination of some postsynaptic ?-1 adrenoreceptor antagonist; doxazosin mesylate (DOX), terazosin (TRZ) and alfuzosine HCl (ALF) in pure forms and pharmaceutical formulations. The developed methods are based on the formation of yellow colored chloroform ion-pair complexes between the basic nitrogen of the drugs and dyes, namely; bromocresol green (BCG), bromothymol blue (BTB), methyl orange (MO) and alizarine red S (ARS), in acidic buffer of pH range (3.0-5.0). The formed complexes were extracted with chloroform or dichloromethane and measured at 418, 414, 425 and 426 nm for DOX and at 419, 415, 425 and 428 for TRZ and at 418, 412, 421 and 427 nm for ALF using BCG, BTB, MO and ARS, respectively. The analytical parameters and their effects on the reported systems are investigated. Beer?s law was obeyed in the range 1.0-130 ?g mL?1 with correlation coefficient (n = 6) ? 0.9991. The molar absorpitivity, Sandell sensitivity, detection and quantification limits were also calculated. The composition of the ion associates was found 1:1 by Job?s method. The proposed methods have been applied successfully for the analysis of the studied drugs in pure forms and in pharmaceutical formulations with percentage recoveries ranges from 99.18-100.61. The results of analysis were validated statistically. The results were in good agreement and compared with those obtained with reported methods. more...
- Published
- 2012
37. Homologous recombination induced by doxazosin mesylate and saw palmetto in theDrosophilawing-spot test
- Author
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Marc François Richter, Rafael Rodrigues Dihl, Katiane Cella Gabriel, Heloisa Helena Rodrigues de Andrade, Maria Luiza Reguly, and Mauricio Lehmann
- Subjects
Mitotic crossover ,Gene mutation ,Biology ,Pharmacology ,urologic and male genital diseases ,Toxicology ,Doxazosin Mesylate ,Loss of heterozygosity ,chemistry.chemical_compound ,Germline mutation ,chemistry ,Saw palmetto ,Finasteride ,Doxazosin ,medicine ,medicine.drug - Abstract
Benign prostatic hyperplasia (BPH) is the most common tumor in men over 40 years of age. Acute urinary retention (AUR) is regarded as the most serious hazard of untreated BPH. α-Blockers, such as doxazosin mesylate, and 5-α reductase inhibitors, such as finasteride, are frequently used because they decrease both AUR and the need for BPH-related surgery. An extract of the fruit from American saw palmetto plant has also been used as an alternative treatment for BPH. The paucity of information available concerning the genotoxic action of these compounds led us to assess their activity as inducers of different types of DNA lesions using the somatic mutation and recombination test in Drosophila melanogaster. Finasteride did not induce gene mutation, chromosomal mutation or mitotic recombination, which means it was nongenotoxic in our experimental conditions. On the other hand, doxazosin mesylate and saw palmetto induced significant increases in spot frequencies in trans-heterozygous flies. In order to establish the actual role played by mitotic recombination and by mutation in the genotoxicity observed, the balancer-heterozygous flies were also analyzed, showing no increment in the total spot frequencies in relation to the negative control, for both drugs. Doxazosin mesylate and saw palmetto were classified as specific inducers of homologous recombination in Drosophila proliferative cells, an event linked to the loss of heterozygosity. more...
- Published
- 2011
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38. Determination of Alkyl Methanesulfonates in Doxazosin Mesylate by Gas Chromatography-mass Spectrometer
- Author
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B.N. Reddy, C.S.P Sastry, C Sitaram, and Ravichandrababu Rupakula
- Subjects
chemistry.chemical_classification ,Detection limit ,validation ,Alkyl methanesulfonate ,Chromatography ,Ethyl methanesulfonate ,Chemistry ,Short Communications ,Pharmaceutical Science ,Mass spectrometry ,Doxazosin Mesylate ,genotoxic ,Methyl methanesulfonate ,chemistry.chemical_compound ,doxazosin mesylate ,method development ,Acetonitrile ,Alkyl ,Isopropyl - Abstract
High sensitive rapid gas chromatography-mass spectrometry method for the determination of four carcinogenic alkyl methanesulfonates viz. methyl methanesulfonate, ethyl methanesulfonate, isopropyl methanesulfonate and n-butyl methanesulfonate in doxazosin mesylate has been presented by using selective ion monitoring mode. The optimum separation was achieved between methyl methanesulfonate, ethyl methanesulfonate, isopropyl methanesulfonate and n-butyl methanesulfonate on a DB-5 (30 m×0.32 mm×1.0 μm) capillary column under programming temperature. Acetonitrile, water and ammonia (90:9:1 v/v/v) mixture was used as diluent. Various factors involved in the gas chromatography-mass spectrometry method development are also presented. This method was validated as per International Conference on Harmonization guidelines. The limit of quantitation of methyl methanesulfonate, ethyl methanesulfonate, isopropyl methanesulfonate and n-butyl methanesulfonate is 6 ppm with respect to 30 mg/ml of doxazosin mesylate. more...
- Published
- 2011
39. Preparation and characterization of controlled-release doxazosin mesylate pellets using a simple drug layering-aquacoating technique
- Author
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Hazzah, Heba A., EL-Massik, Magda A., Abdallah, Ossama Y., and Abdelkader, Hamdy
- Published
- 2013
- Full Text
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40. Selective α1-adrenoceptor antagonist (controlled release tablets) in preoperative management of pheochromocytoma
- Author
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Juping Zhao, Guang Ning, Chongyu Zhang, Yuxuan Wu, Hong-chao He, Zhoujun Shen, Wen-bin Rui, Tingwei Su, Wenlong Zhou, Weiqing Wang, Yu Zhu, and Fukang Sun
- Subjects
Adult ,Male ,Adolescent ,Phenoxybenzamine ,Endocrinology, Diabetes and Metabolism ,Adrenal Gland Neoplasms ,Hemodynamics ,Blood Pressure ,Pheochromocytoma ,urologic and male genital diseases ,Preoperative care ,Young Adult ,Endocrinology ,Preoperative Care ,medicine ,Doxazosin ,Humans ,Intraoperative Complications ,Adrenergic alpha-Antagonists ,Aged ,business.industry ,Perioperative ,Middle Aged ,medicine.disease ,Doxazosin Mesylate ,Blood pressure ,Delayed-Action Preparations ,Anesthesia ,Adrenergic alpha-1 Receptor Antagonists ,Fluid Therapy ,Female ,business ,medicine.drug - Abstract
The objective of this article is to evaluate the efficacy of Doxazosin Mesylate Controlled Release Tablets for preoperative treatment of patients with pheochromocytoma. Between 2003 and 2008, 67 patients with confirmed diagnoses of pheochromocytoma were enrolled in this study. According to the drug used in preoperative management, patients were divided into two groups: Doxazosin Mesylate pretreatment group (n = 36) and Phenoxybenzamine pretreatment group (n = 31). Surgery was performed only in patients who met the optimal preoperative condition. The hematocrit decreased significantly (P < 0.001) after antiadrenergic therapy in patients pretreated with phenoxybenzamine or doxazosin. There was no significant difference between the fluid intakes during operation in both groups. The systolic arterial pressures both before and after induction of anesthesia were all significantly higher in the doxazosin patients than in the phenoxybenzamine group (P < 0.05). After tumor removed, the lowest systolic arterial pressure was significantly higher in doxazosin group than in phenoxybenzamine group (P < 0.05). The fluctuation of systolic arterial pressure during operation was more stable in doxazosin group than in phenoxybenzamine group (P < 0.05). Doxazosin mesylate controlled release tablet was as effective as phenoxybenzamine in preoperative volume expansion. Although phenoxybenzamine provided better arterial pressure control, patients pretreated with DOX experienced more stable perioperative hemodynamic changes, shorter preoperative management periods and more simple medication. more...
- Published
- 2010
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41. A LC-MS-MS Method for Determination of Low Doxazosin Concentrations in Plasma after Oral Administration to Dogs
- Author
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Lidija Pozaic Frketic, Maria Vertzoni, Christos Reppas, Marijana Erceg, Biserka Cetina-Čižmek, and Mario Cindrić
- Subjects
Electrospray ionization ,Administration, Oral ,urologic and male genital diseases ,High-performance liquid chromatography ,Analytical Chemistry ,LC-MS-MS ,doxazosin ,plasma concentrations ,Dogs ,Limit of Detection ,Tandem Mass Spectrometry ,Doxazosin ,medicine ,Animals ,Adrenergic alpha-Antagonists ,Detection limit ,Chromatography, Reverse-Phase ,Chromatography ,Elution ,Chemistry ,General Medicine ,Reversed-phase chromatography ,Doxazosin Mesylate ,Calibration ,Female ,Quantitative analysis (chemistry) ,medicine.drug - Abstract
A rapid and sensitive reversed phase liquid chromatography- tandem mass spectrometry (LC-MS-MS) method is developed for the determination of doxazosin in canine plasma. The samples are prepared by precipitation of proteins using a mixture of methanol and acetonitrile, followed by freezing and evaporation of the organic solvent. The remaining dry residue is redissolved in mobile phase and analyzed by LC-MS-MS with positive electrospray ionization using the selected reactions monitoring mode. An XTerra MS C(18) column, a mobile phase composed of acetonitrile and 2mM ammonium acetate with gradient elution, and a flow rate of 400 microL/min are employed. The elution times for prazosin (internal standard) and doxazosin are approximately 8 and 10 min, respectively. Calibration curves are linear in the 1-20 ng/mL concentration range. Limits of detection and quantification are 0.4 ng/mL and 1.2 ng/mL, respectively. Recovery is higher than 94%. Intra- and inter-day relative standard deviations are below 7% and 8%, respectively. The method is applied for the determination of doxazosin plasma levels following a single administration of doxazosin base and doxazosin mesylate tablets (2 mg dose) to dogs in the fed state. The results indicate possible superiority of the mesylate salt on the plasma input rates of doxazosin. more...
- Published
- 2010
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42. Doxazosin mesylate affects localization of endothelin-1 in prostatic tissues
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Andrzej Marszałek, Stanisław Wroński, Halina Wiśniewska, Dariusz Grzanka, and Jadwiga Korenkiewicz
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medicine.medical_specialty ,Pathology ,Prostate biopsy ,Stromal cell ,medicine.diagnostic_test ,business.industry ,General Medicine ,Endothelin 1 ,Epithelium ,Doxazosin Mesylate ,medicine.anatomical_structure ,Stroma ,Prostate ,medicine ,Histopathology ,business - Abstract
Introduction. Data suggest that not only alpha-adrenergic factors contribute to contractility of smooth muscles of the prostate. The authors determined the influence of doxazosin mesylate on localization of endothelin-1 in prostatic tissue in treated and non-treated patients. Material and methods. Seventy patients with symptoms of prostate enlargement: 40 patients preliminary treated with doxazosin mesylate and 30 non-treated patients. All underwent prostate biopsy due to elevated PSA level (mean 5.85 ng/ml). Specimens were H&E stained for histopathology which confirmed diagnosis of benign hyperplasia and immunohistochemically stained for ET-1 in epithelium and prostate stroma. Authors calculated ET-1 mean optical density ratios (epithelial ET-1/stromal ET-1) for treated and non-treated patients. Statistical analysis was performed. Ratios of ET-1 in epithelium and stroma of both groups differed statistically. Conclusions. Obtained data indicate that relocation of endothelin-1 from prostate epithelium to stroma is altered in the treated group in comparison with the non-treated group. Doxazosin mesylate might have an influence on ET-1 redistribution from the epithelial compartment to the non-epithelial environment. This could be an additional mechanism of action of alphaadrenergic blockers in BPH patients. more...
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- 2010
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43. Spectroscopic Studies and Applications of the Reactions of Some Anti-Diabetic and Anti-Hypertensive Drugs with Rose Bengal
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Zayed Ma and Farrag Ys
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Drug ,Chromatography ,Chemistry ,Chromogenic ,Stereochemistry ,media_common.quotation_subject ,PIOGLITAZONE HCL ,Dosage form ,Doxazosin Mesylate ,Terazosin hcl ,chemistry.chemical_compound ,Reagent ,Rose bengal ,media_common - Abstract
Simple, rapid and sensitive spectrophotometric methods were developed and validated for the microdetermination of terazosin HCl, doxazosin mesylate and pioglitazone HCl drugs in pure and pharmaceutical dosage forms. These methods are based on ion-pair formation reaction between these drugs and a chromogenic reagent Rose Bengal (RBeng). These reactions were studied under various conditions and the optimum parameters were selected. The spectrophotometric microdeterminations have been done at λmax=570 nm for terazosin HCl and pioglitazone HCl and at λmax=575 nm for doxazosin mesylate. Under proper conditions the suggested procedures were successfully applied for microdetermination of these drugs in pure and in pharmaceutical dosage forms. The values of SD, RSD, recovery %, LOD, LOQ and Sandell sensitivity refer to the high accuracy and precession of the applied procedures. The results obtained were compared with the data obtained by the official methods, referring to confidence and agreement with rose bengal procedure results. The solid drugs-reagent ion-pairs were prepared, separated and their structures were investigated using elemental analysis, FT-IR, 1H-NMR and thermal analyses and the results confirm the structures proposed by the stoichoimetric ratio in the solution work. The biological activities of the drugs and their solid ion-pairs against some types of (G-) and (G+) bacteria and fungai were studied and compared with each other. It is found that terazosin-RBeng and pioglitazone-RBeng reaction products have antibacterial effect higher than the parent drugs, but doxazosin-RBeng reaction product has almost the same antibacterial effect of the parent drug. more...
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- 2016
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44. Pharmacokinetics of Doxazosin Gastrointestinal Therapeutic System after Multiple Administration in Korean Healthy Volunteers
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Hye Sun Gwak, Yoon Hee Kwon, Sun Jung Yoon, and In Koo Chun
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Adult ,Male ,Pharmaceutical Science ,urologic and male genital diseases ,High-performance liquid chromatography ,Sex Factors ,Asian People ,Pharmacokinetics ,Oral administration ,Drug Discovery ,Healthy volunteers ,Doxazosin ,medicine ,Prazosin ,Humans ,Adrenergic alpha-Antagonists ,Chromatography, High Pressure Liquid ,Pharmacology ,Korea ,Chromatography ,Chemistry ,Organic Chemistry ,Antagonist ,Doxazosin Mesylate ,Area Under Curve ,Delayed-Action Preparations ,Female ,Half-Life ,medicine.drug - Abstract
Doxazosin mesylate is a selective alpha-adrenoreceptor antagonist for the treatment of hypertension and benign prostatic hyperplasia. A simple high performance liquid chromatographic method has been developed and validated for the quantitative determination of doxazosin in plasma. A reversed phase C18 column was used for the separation of doxazosin and prazosin (internal standard) with a mobile phase composed of water, acetonitrile, triethylamine (68:32:0.2 v/v, pH 5.0) at a flow rate of 1.2 mL/min. The fluorescence detector was operated at 246 (excitation) and 389 nm (emission). Intra- and inter-day precision and accuracy were acceptable for all quality control samples including the lower limit of quantification of 1 ng/mL. Recovery of doxazosin from human plasma was greater than 93.4%. Doxazosin was stable in human plasma under various storage conditions. This method was used successfully for a pharmacokinetic study in plasma after oral administration of multiple 4-mg dose of doxazosin gastrointestinal therapeutic system formulation to 16 healthy volunteers. At steady state the mean area under the curve for a dosing interval and elimination half-life were calculated to be 367.0 +/- 63.5 ng x hr/mL and 29.2 +/- 4.5 hr, respectively. There was no difference in pharmacokinetic parameters between male and female. more...
- Published
- 2007
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45. Synthesis, vasorelaxant activity and 2D-QSAR study of some novel pyridazine derivatives
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Riham F. George and Dalia O. Saleh
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Male ,Quantitative structure–activity relationship ,Stereochemistry ,Vasodilator Agents ,Quantitative Structure-Activity Relationship ,Aorta, Thoracic ,010402 general chemistry ,01 natural sciences ,Pyridazine ,chemistry.chemical_compound ,Drug Discovery ,Aortic rings ,Animals ,Rats, Wistar ,Reference standards ,Pharmacology ,Dose-Response Relationship, Drug ,Molecular Structure ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,General Medicine ,Doxazosin Mesylate ,0104 chemical sciences ,Rats ,Pyridazines ,Vasodilator agents ,Software - Abstract
Novel 3,6-disubstituted pyridazines were synthesized by facile method and screened for their vasorelaxant properties utilizing isolated thoracic rat aortic rings. Compounds 8a and 11a exerted potent vasorelaxant activity (IC50 = 198 and 177 μM, respectively) relative to doxazosin mesylate (used reference standard, IC50 = 226 μM), that, they may represent promising hits for treatment of cardiovascular disorders. The observed activity was validated by a statistically significant QSAR model (N = 32, n = 6, R(2) = 0.811782, R(2)cvOO = 0.7153, R(2)cvMO = 0.7209, F = 17.9708, s(2) = 9.65226 × 10(-8)) that was obtained employing CODESSA-Pro software. more...
- Published
- 2015
46. Highly sensitive spectrofluorimetric method for determination of doxazosin through derivatization with fluorescamine; Application to content uniformity testing
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Baher I. Salman, Sayed M. Derayea, Mahmoud A. Omar, and Mohamed A. Hammad
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Accuracy and precision ,Calibration curve ,Analytical chemistry ,02 engineering and technology ,Fluorescamine ,01 natural sciences ,Analytical Chemistry ,chemistry.chemical_compound ,Limit of Detection ,Doxazosin ,medicine ,Humans ,Derivatization ,Instrumentation ,Spectroscopy ,Antihypertensive Agents ,Detection limit ,Chromatography ,010401 analytical chemistry ,Buffer solution ,021001 nanoscience & nanotechnology ,Atomic and Molecular Physics, and Optics ,Doxazosin Mesylate ,0104 chemical sciences ,Spectrometry, Fluorescence ,chemistry ,Pharmaceutical Preparations ,0210 nano-technology ,medicine.drug - Abstract
A highly sensitive, simple and selective spectrofluorimetric method has been developed and validated for determination of doxazosin mesylate in pure form, pharmaceutical formulations and human plasma. The method is based on the reaction between doxazosin mesylate and fluorescamine in Teorell buffer solution (pH 3) to give highly fluorescent derivative that can be measured at 489 nm using excitation wavelength of 385 nm. Different experimental parameters affecting the reaction were carefully studied and optimized. The calibration plot was constructed over the concentration range of 16-400 ng mL(-1) with quantitation limit of 14.3 ng mL(-1). The developed procedure was validated according to ICH guidelines and the results were satisfactory. The proposed method has been successfully applied to the analysis of the cited drug in its pharmaceutical preparations as well as for content uniformity testing. The results showed excellent agreement with the reported method with respect to precision and accuracy. In addition, the drug concentration was determined in the spiked human plasma by the suggested method with % recovery in the range of 96.2-98.3% (SD; 0.76-0.93, n=5). more...
- Published
- 2015
47. Development and validation of a reversed-phase HPLC method for monitoring of synthetic reactions during the manufacture of a key intermediate of an anti-hypertensive drug
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Nivedita Jena, Gullapalli Kumaraswamy, Dongari Nagaraju, and Ramisetti Nageswara Rao
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Quality Control ,Detection limit ,Chromatography ,medicine.diagnostic_test ,Chemistry ,Filtration and Separation ,Reversed-phase chromatography ,Chemical synthesis ,High-performance liquid chromatography ,Doxazosin Mesylate ,Analytical Chemistry ,Terazosin ,Spectrophotometry ,Quinazolines ,medicine ,Spectrophotometry, Ultraviolet ,Drug Contamination ,Quantitative analysis (chemistry) ,Antihypertensive Agents ,Chromatography, High Pressure Liquid ,medicine.drug - Abstract
A reversed-phase high-performance liquid-chromatographic method for monitoring of reactions involved in process development of a key intermediate of antihypertensive drugs, e.g, doxazosin mesylate, prazosin, alfuzosin, terazosin, etc., has been developed and validated. The HPLC profiles of impurities of 4-amino-2-chloro-6,7-dimethoxyquinazoline were used as fingerprints to follow the synthetic procedures in the manufacturing unit. The separation was accomplished on an Inertsil ODS-3 column with isocratic elution using acetonitrile-ammonium acetate (10 mM; pH 4.0; 50:50 v/v) as mobile phase and a photodiode array detector set at 240 nm at ambient temperature. The method was validated with respect to accuracy, precision, linearity, and limits of detection and quantification. The method could detect the impurities at a level of 0.01 to 0.20 microg/mL and it was found to be suitable not only for monitoring of reactions but also for quality assurance of 4-amino-2-chloro-6,7-dimethoxyquinazoline. more...
- Published
- 2006
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48. Syntheses of molecularly imprinted polymers and their molecular recognition study for doxazosin mesylate
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Huai You Wang, Li Ying Ma, Yan Ling Pang, and Ji Gang Jiang
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chemistry.chemical_classification ,Polymers and Plastics ,Chemistry ,General Chemical Engineering ,Molecularly imprinted polymer ,General Chemistry ,Polymer ,Biochemistry ,Doxazosin Mesylate ,chemistry.chemical_compound ,Molecular recognition ,Polymerization ,Methacrylic acid ,Polymer chemistry ,Materials Chemistry ,Environmental Chemistry ,Radical initiator ,Molecular imprinting - Abstract
Molecular imprinted polymers (MIPs) (diameter is about 1.7 μm) were prepared from methacrylic acid as the functional monomer and triallyl isocyanurate as the cross-linker in methanol solution using doxazosin mesylate as the template molecule and 2,2′-azobis-isobutyronitrile as the initiator. The effects of amount of the cross-linker, the ratio of template molecule and functional monomer, amount of solvent and amount of the radical initiator on the polymerization were examined. Release of the template was performed by continuous extraction with methanol containing 10% acetic acid. These MIPs showed specific binding affinity toward doxazosin mesylate and the imprinting mechanism is discussed. The principal advantage of the method is that the MIPs prepared can recognize doxazosin mesylate and the particles size can be controlled by the amount of initiator and the volume of methanol employed. more...
- Published
- 2005
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49. Prostate apoptosis after doxazosin treatment in the spontaneous hypertensive rat model
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A. Moreno, Marcos Lujan, Alvaro Paez, A. Berenguer, and A. Ferruelo
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Male ,medicine.medical_specialty ,Adenoma ,Urology ,medicine.medical_treatment ,Prostatic Hyperplasia ,Apoptosis ,urologic and male genital diseases ,Rats, Inbred WKY ,Cohort Studies ,Prostate ,Rats, Inbred SHR ,Internal medicine ,Doxazosin ,medicine ,Animals ,RNA, Messenger ,cardiovascular diseases ,Spontaneous hypertensive rat ,Antihypertensive Agents ,Analysis of Variance ,Chemotherapy ,Reverse Transcriptase Polymerase Chain Reaction ,business.industry ,Hyperplasia ,medicine.disease ,Doxazosin Mesylate ,Rats ,medicine.anatomical_structure ,Endocrinology ,Caspases ,Hypertension ,business ,medicine.drug - Abstract
OBJECTIVE To validate the spontaneous hypertensive rat (SHR) model for basic research into benign prostate hyperplasia (BPH), and to assess doxazosin-induced changes in prostatic structure and apoptotic status. MATERIALS AND METHODS Four groups of rats were assessed: group 1, 15 SHRs treated with doxazosin; group 2, 14 SHRs with unilateral excision of the major pelvic ganglion; group 3, 14 untreated SHRs; and group 4, 16 intact Wistar-Kyoto (WKY) rats. The doxazosin mesylate (0.03 mg daily) was given compacted in rat food for 3 months. The prostatic ventral lobe (VL) was excised and weighed. Stereological light microscopy, multiplex reverse transcription-polymerase chain reaction of prostate caspases, and caspase-3 activity (cellular enzymatic assay) were assessed. RESULTS There was more development of the glandular epithelium (P more...
- Published
- 2004
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50. Altered pharmacokinetics and excessive hypotensive effect of candesartan in a patient with the CYP2C9*1/*3 genotype
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Shinya Uchida, Kyoichi Ohashi, Shinichiro Nishio, Keisuke Yamazaki, Hisakuni Hashimoto, Hiroshi Watanabe, and Hideharu Hayashi
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Male ,Genotype ,Tetrazoles ,Blood Pressure ,Pharmacology ,chemistry.chemical_compound ,Doxazosin ,medicine ,Humans ,Pharmacology (medical) ,Antihypertensive Agents ,Aged ,Cytochrome P-450 CYP2C9 ,Aged, 80 and over ,Heart Failure ,Polymorphism, Genetic ,Chemistry ,Biphenyl Compounds ,Furosemide ,medicine.disease ,Angiotensin II ,Doxazosin Mesylate ,Candesartan ,Blood pressure ,Area Under Curve ,Heart failure ,Hypertension ,Benidipine ,Benzimidazoles ,Aryl Hydrocarbon Hydroxylases ,Angiotensin II Type 1 Receptor Blockers ,medicine.drug - Abstract
An 89-year-old man with severe hypertension (190/82 mm Hg) and chronic heart failure (New York Heart Association class II) despite treatment with benidipine, doxazosin mesylate (INN, doxazosin), and furosemide was given oral candesartan cilexetil (4 mg/d), an angiotensin II type 1 receptor blocker metabolized via cytochrome P450 (CYP) 2C9. Two days later, he started to have severe dizziness and returned to the hospital on the fourth day without taking any of his medications. The blood pressure 30 hours after the last dose of candesartan was 126/64 mm Hg. Polymorphism analysis revealed the heterozygous poor metabolizer genotype CYP2C9*1/*3. The area under the concentration-time curve and the mean residence time of candesartan were both increased 2.5-fold, and the oral clearance of candesartan was 48% lower than that of the average elderly Japanese patient with hypertension. These results suggest that the CYP2C9*1/*3 genotype could be associated with decreased clearance and increased plasma concentration of candesartan, potentially enhancing its hypotensive effect. Clinical Pharmacology & Therapeutics (2003) 74, 505–508; doi: 10.1016/j.clpt.2003.08.001 more...
- Published
- 2003
- Full Text
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