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Background: The detection of lactate is an important indicator of freshness, stability, and storage stability of products as well as degree of fermentation in food industry. In addition, it can be used as a diagnostic tool in patients’ healthcare since it is known that the lactate level in blood increases in some pathological conditions including septic shock, tissue hypoxia, and sepsis. Thus, determination of lactate level plays an important role in not only food industry but also health fields. At this point, biosensor has become important to detect lactate due to having many advantages like rapid, cheap and easy to use. Methods and Results: In the current study, amperometric lactate biosensors based on lactate oxidase immobilization (with nafion 5% wt) were designed and limit of detection, linear range and sensitivity values were determined, which were found as 31 μM, 50-350 μM and 0.04 μA.μM-1.cm-2, respectively. Then, it was used for the measurement of lactic acid produced by 6 different and morphologically identified presumptive lactic acid bacteria (LAB) which were isolated from different naturally fermented cheese samples for this study. Then, the biosensors were used to perform lactate measurements successfully within 3 minutes for each sample even few of them were out of the limit of detection. Conclusion: Electrochemical biosensors should be alternative and quick solutions for measurement of lactate metabolites instead of using classical methods which are required long working time. Besides, it is the first study to measure lactate produced by foodborne LAB as real sample with a biosensor.

Bu çalışma, Bursa Uludağ Üniversitesi Fen Bilimleri Enstitüsünde Mihriban Korukluoğlu ve Evrim Güneş Altuntaş'ın danışmanlığında Özüm Özoğlu tarafından yazılan "Enzim temelli amperometrik laktat biyosensörü üretimi ve tayin sınırının belirlenmesi" adlı yüksek lisans tezine dayanılarak hazırlanmıştır. Laktik asit bakterileri pek çok fermente ve probiyotik gıdanın bünyesinde yer alan faydalı bakterilerdir. Bu bakterileri önemli kılan özellikleri arasında GRAS (Generally Recognized As Safe) statüde olmaları ve ürettikleri antimikrobiyal metabolitler bulunmaktadır. Laktik asit bakterilerinin ürettiği antagonistik etkiye sahip en önemli metabolit bu gruba adını veren laktik asit olup; bunun yanısıra hidrojen peroksit, asetik asit, diasetil, bakteriyosin vb. metabolitler ile de antagonistik etkiye neden olmaktadırlar. Bu çalışmada çeşitli peynir, sucuk ve kefir örneklerinden izole edilen 23 adet muhtemel laktik asit bakteri izolatının Salmonella Enteritidis ATCC 13076, Streptococcus mutans ATCC 25175, Escherichia coli ATCC 25922, Bacillus subtilis ATCC 6633 ve Staphylococcus aureus ATCC 43300 (metisilin ve oksasilin dirençli) patojenleri üzerindeki inhibisyon etkisi Agar Spot Yöntemi ile araştırılmıştır. Test sonucunda pozitif etki gösteren izolatların süpernatantları ile Kuyu Difüzyon denemesi gerçekleştirilmiştir. Son olarak izolatların ürettiği laktik asit miktarları HPLC yöntemi ile de belirlenmiştir. Agar Spot Testi’ne göre izolatların neredeyse tamamı tüm patojenler üzerinde etkinlik gösterirken, patojenler üzerindeki inhibisyon etkiyi gösteren zon çaplarının 1-24.5 mm aralığında değiştiği tespit edilmiştir. 24.5 mm zon çapı ile maksimum etki 31 nolu izolat tarafından E.coli ATCC 25922 üzerinde gözlemlenirken; 1 mm zon çapı ile minimum etki 431 nolu izolat tarafından S. Enteritidis ATCC 13076 test mikroorganizmasına karşı gözlemlenmiştir. Kuyu Difüzyon Testi’nde ise hiçbir pozitif sonuç elde edilememiş ve bu nedenle bakterilerin antagonistik etkilerinin daha çok laktik asit üretiminden kaynaklandığı düşünülmüştür. Yapılan kromatografik çalışma ile laktik asit bakterilerinin ürettiği laktik asit miktarının 0.13-5.52 mmol aralığında olduğu gözlenmiştir. Çalışmadan elde edilen sonuçlar laktik asit bakterilerinin bakteriyosin gibi önemli protein bazlı inhibitörleri üretmese bile, ürettiği temel metabolit olan laktik asit ile etkin bir antimikrobiyal aktivite kapasitesine sahip olduğunu göstermektedir. Lactic acid bacteria are useful bacteria which are included to composition of many fermented and probiotic food. Being GRAS (Generally Recognized As Safe) statute and the antimicrobial metabolites produced by them are among the properties which make these bacteria significant. The most important metabolite with antagonistic effect produced by lactic acid bacteria is lactic acid that gives the name of these bacteria, besides LAB can have antagonistic effect by producing hydrogen peroxide, acetic acid, diacetyl, bacteriocin etc. In this study, inhibition effects of 23 presumptive lactic acid bacteria isolates that isolated from various cheese, sucuk and kefir samples on Salmonella Enteritidis ATCC 13076, Streptococcus mutans ATCC 25175, Escherichia coli ATCC 25922, Bacillus subtilis ATCC 6633 and Staphylococcus aureus ATCC 43300 (methicillin and oxacillin resistant) were investigated by Agar Spot method. According to the assay, Well Diffusion Test was performed with supernatant of the isolates showed positive results. Finally, the quantification of lactic acid was detected by HPLC method. As a result of Agar Spot Test, while all of the isolates were effective on all pathogens, the inhibition zone diameters were ranged between 1-24.5 mm. While the maximum effect was observed by isolate 31 on E.coli ATCC 25922 with a zone diameter of 24.5 mm, the minimum effect was observed by isolate 431 against S. Enteritidis ATCC 13076 test microorganism with a zone diameter of 1 mm.Then, due to not to have any positive results from Well Diffusion Assay, it has been considered the antagonistic effect of the bacteria were originated from lactic acid production. It was observed that lactic acid produced by LAB was ranged between 0.13-5.52 mmol by chromatographic study. Even if the LAB do not produce protein-based inhibitors such as bacteriocin, the results shows LAB has an effective antimicrobial activity capacity with lactic acid, the main metabolite of LAB.

Honeybee products have been among important consumer products throughout history. Microbiota has attracted attention in recent years due to both their probiotic value and industrial potential. Fructophilic lactic acid bacteria (FLAB), whose field of study has been expanding rapidly in the last 20 years, are among the groups that can be isolated from the bee gut. This study aimed to isolate FLAB from the honeybees of two different geographic regions in Turkey and investigate their probiotic, metabolic and anti-quorum sensing (anti-QS) potential. Metabolic properties were investigated based on fructose toleration and acid and diacetyl production while the probiotic properties of the isolates were determined by examining pH, pepsin, pancreatin resistance, antimicrobial susceptibility, and antimicrobial activity. Anti-QS activities were also evaluated with the Chromobacterium violaceum biosensor strain. Two FLAB members were isolated and identified by the 16S rRNA analysis as Fructobacillus tropaeoli and Apilactobacillus kunkeei, which were found to be tolerant to high fructose, low pH, pepsin, pancreatin, and bile salt environments. Both isolates showed anti-QS activity against the C. violaceum biosensor strain and no diacetyl production. The daily supernatants of the isolates inhibited the growth of Enterococcus faecalis ATCC 29212 among the selected pathogens. The isolates were found resistant to kanamycin, streptomycin, erythromycin, and clindamycin. In the evaluation of the probiotic potential of these species, the negative effect of antibiotics and other chemicals to which honeybees are directly or indirectly exposed draws attention within the scope of the "One Health" approach.

In this article, a serially connected dual column liquid chromatography-tandem mass spectrometry (LC-MS/MS) method is described for the simultaneous separation and enantioseparation of proteinogenic amino acids. For this purpose, different achiral and chiral stationary phases (CSP) and mobile phase compositions have been tested. As a result of the optimization studies, the best enatioseparation for amino acids were achieved with a combination of zwitterionic and crown ether stationary phases using a gradient of two mobile phases: A (water:TFA 99.5:0.5, % v/v) and B (acetonitrile:ethanol:TFA 85:15:0.5, % v/v/v). The developed method provided simultaneous enantioseparation of all proteinogenic amino acids under this study including isomeric and isobaric ones except for proline. The method was successfully applied to human lung adenocarcinoma cells (A549) and healthy human lung epithelial cells (BEAS-2B) cultivated with d-amino acid containing cocktails in order to evaluate d-amino acids transfer rate in normal and cancer lines. Thed/l amino acid ratios were different in cancer and normal cell lines cultivated as mentioned above for aspartic acid, cysteine, methionine, phenylalanine, and serine.

Interest in the production of exopolysaccharides by microorganisms has increased in the recent years. Using low-cost product is the main step of microbial production to reduce cost and compete with chemical production. In this work, EPS production of Streptococcus thermophilus isolates from yogurt (S2), kefir (S3), and S. thermophilus ATCC 19258 (S1) isolate which was used as control strains were investigated by using different fruit pulps. S. thermophilus isolates were identified by morphological and 16S sequence analysis. The amount of EPS obtained was measured spectrophotometrically using glucose as standard with phenol sulfuric acid method. All three isolates produced higher amounts of EPS on M17 medium than Nutrient medium. When the fruit pulp was added to the medium, EPS production increased in all three isolates. When different nitrogen sources were added together with fruit pulp juice, EPS production increased. The highest amount of EPS produced by ATCC 19258 strain (21.570 mg/L) and S3 isolate (29.131 mg/L) is the medium where mixed fruit pulp juice and nitrogen source is tryptophan. It has been shown that EPS production is increased by adding fruit pulps to the prepared media. It is thought that apricot pulp can be a good alternative in EPS production especially in the evaluation of wastes. Also, antiquorum sensing activity of the highest amount EPS was determined by using Chromobacterium violaceum CV026 strain and found effective on violacein pigment inhibition and C6-AHL production of biosensor strain.

The aim of the present study is to develop the polymeric nanoparticulate drug delivery systems of piroxicam and to evaluate the in-vitro characteristics such as entrapment efficiency, surface morphology, in-vitro drug release performance, etc. For this reason, a novel HPLC methodology was developed for the determination of piroxicam from its bulk form, pharmaceutical preparation, and nanoparticulate delivery systems. Furthermore, the developed formulation was applied to the rats and the biological samples (plasma, liver, heart, spleen, kidney, and lung homogenates) were analyzed by the developed HPLC method following a salting-out assisted liquid-liquid extraction strategy for the first time in the literature. A Kinetex C18 analytical column (150 mm × 4.6 mm i.d., 5 µm) was used as a stationary phase with a 0.8 mL/min flow rate of acetonitrile: phosphate buffer (40:60, v/v), the column oven was adjusted to 40 °C and detection wavelength is set to 360 nm. Developed method were validated as per selectivity, linearity, LOD, LOQ, precision, and accuracy specified in the International Council for Harmonisation guidelines. As a result of the present study, it has been shown that the analysis of piroxicam from the bulk form, pharmaceutical preparation, developed polymeric-based drug delivery system, and biological samples can be successfully performed and no interferences were observed in any matrix. The developed method was also successfully utilized to study the tissue distribution of piroxicam in rats.

Drug resistance is one of the main problems of cancer treatment. For this reason, combination therapy is commonly used for years. The combination of a chemotherapeutic, carboplatin, and the epigenetic drug decitabine is a new approach to modulate drug resistance. Nanoparticulate systems can overcome the drawbacks associated with the drug combinations. An analytical method that can detect and quantify carboplatin and decitabine which is encapsulated into the nanoparticles is necessary for nanoparticle development. In the literature, there is no analytical method in which carboplatin and decitabine are determined simultaneously. The primary purpose of this study is to develop and validate a novel, and stability-indicating high-performance liquid chromatography method for simultaneous determination of carboplatin and decitabine in pharmaceutical preparations in addition to developing the first nanoformulation for this drug combination. Therefore, various experimental parameters were optimized. The chromatographic separation was achieved using an XSelect(R)CSH C18 (250 x 4.6 mm I.D., 5 mu m) column and a mobile phase consisting of methanol:water (containing 0.1% phosphoric acid) (3:97, v/v). The mobile phase pH was adjusted to 7.0 with 5 M NaOH. The developed method was successfully applied for the simultaneous determination and quantification of carboplatin and decitabine co-encapsulated in nanoparticles and released into in vitro dissolution medium.

In the present study, the enantiomer migration order (EMO) of enilconazole in the presence of various cyclodextrins (CDs) was investigated by capillary electrophoresis (CE). Opposite EMO of enilconazole were observed when β-CD or the sulfated heptakis(2-O-methyl-3,6-di-O-sulfo)-β-CD (HMDS-β-CD) was used as the chiral selectors. Nuclear magnetic resonance (NMR) spectroscopy was used to study the mechanism of chiral recognition between enilconazole enantiomers and those two cyclodextrins. On the basis of rotating frame nuclear Overhauser (ROESY) experiments, the structure of an inclusion complex between enilconazole and β-CD was derived, in which (+)-enilconazole seemed to form a tighter complex than the (-)-enantiomer. This correlates well with the migration order of enilconazole enantiomers observed in CE. No evidence of complexation between enilconazole and HMDS-β-CD could be gathered due to lack of intermolecular nuclear Overhauser effect (NOE). Most likely the interaction between enilconazole and HMDS-β-CD leads to formation of a shallow external complex that is sufficient for separation of enantiomers in CE but cannot be evidenced based on ROESY experiment. Thus, in this particular case CE documents the presence of intermolecular interactions which are at least very difficult to be evidenced by other instrumental techniques.

The aim of this study is to develop a selective liquid chromatographic method for the simultaneous determination of tamsulosin HCl and dutasteride which are used for prostate treatment, in the context of an analytical column that is packed with superficially porous particles. Therefore, compositions of the mobile phase were determined for the best separation of these compounds. For this reason, experimental conditions such as varied pH values of buffer solution, temperature of the column, additives, flow rate of mobile phase and different buffer solutions were optimized. As the final condition, Kinetex C 18 analytical column (150 × 4.6; 5 µm) (Phenomenex, USA) and an acetonitrile/water 60: 40 (v/v), 0.1% o-phosphoric acid (pH adjusted to 7.0 using 5 M with NaOH) as a mobile phase are used for the best chromatographic separation. The separation was carried out at 45 °C column temperature with detection at 220 nm, and rilpivirine was chosen as an internal standard. As a result, the proposed method under optimum conditions is easy of application, rapid, precise, sensitive, accurate and fully validated. Furthermore, there is no need for time-consuming sample preparation technique, and because of this reason, it can be applied to quality control laboratories simply. Also, the optimized method can be successfully applied for the in vitro biological samples.

Combined therapy for HIV treatment shows superior efficacy in comparison to single therapy. Furthermore, the separation and determination of the combined dosage forms hold a significant place in the pharmaceutical industry. Not only reverse phase high-performance liquid chromatography (HPLC) but also hydrophilic interaction liquid chromatography (HILIC) can be used for these purposes. Contrary to conventional RP systems, HILIC may be an alternative for the analysis of polar substances. The aim of this study was the step-by-step development of a simple, rapid, and reliable method for the simultaneous determination of antiviral compounds from their marketed formulation (Trizivir). In order to achieve this goal, various mobile phase systems, buffer types, and concentrations were prepared to provide an appropriate separation. Different types of columns were tested to find the best resolution and high efficiency for the studied compounds. The proposed method provided a simple procedure for the simultaneous analysis of abacavir, lamivudine, and zidovudine in their pharmaceutical preparation within approximately 2 min using the conventional HPLC system. The developed method was fully validated according to the International Council for Harmonisation guidelines from the viewpoint of selectivity, sensitivity, precision, accuracy, linearity, limit of detection, and quantification.

High performance liquid chromatography-electrochemical detector (HPLC-EC) is employed as a reliable device for the detection of catecholamines in blood or urine samples without any time-consuming extraction procedure. However, there is a need for the construction of cheap and easy-to-operate electrode assemble systems embedded in HPLC-EC. In this study, we present a disposable and low-cost paper-based electrode (PBE) assemble utilizing a nitrocellulose membrane, which serves support material in flow-cell device for HPLC-EC. A custom-built flow cell was inventively designed as specific to the prepared PBEs via stereolithography 3D printing. To gain the electrochemical signal enhancement, the working electrode was modified with gold nanoparticles and carboxylated-multi-walled carbon nanotubes (MWCNTs). Here, we focused on the construction of the paper-based electrode assemble and characterization of the flow cell device performance. To demonstrate the functionality of the flow cell device, we analyzed common catecholamines from spiked biological fluids using the optimized experimental parameters. Amperometric detection of the catecholamines was carried out at the potential of + 0.5 V and linear range was found to be 0.5–20.0 μg/mL, with a limit of detection in the range of 4.0–15.0 ng/mL. The obtained results confirmed our disposable paper-based electrode assemble to be promising for the construction of an electrochemical platform for reliable and fast detection of electroactive species.

Background:Probiotics are living microorganisms that have a healthy influence on a host.Objective:The aim of this study was to isolate a probiotic Pediococcus acidilactici strain from newborn faeces and develop and optimize a selective high-performance liquid chromatography method for the determination and validation of its lactic acid content and also evaluate some probiotic characteristics.Methods:Isolated strains were identified by the API 50 CH system and 16S rDNA gene sequence analysis and tested for antibiotic susceptibility, bile salt tolerance, low pH resistance, proteolytic, haemolytic activity, as well as the production of bacteriocin, hydrogen peroxide, and lactic acid. Antimicrobial activity of selected strain against standard test microorganisms was determined by the spot lawn method and the quantitation of lactic acid was carried out by high-performance liquid chromatography on a Rezex ROA organic acid (300x7.8 mm) analytical column.Results:P. acidilactici M7 strain was evaluated as a potential probiotic due to its ability to survive at low pH values or in the presence of pepsin, pancreatin, and bile salts. The lactic acid amount of strain was found in the range between 5.59-5.94 mg mL-1 by HPLC. M7 strain was also found to be resistant to vancomycin, had no bacteriocin, and hydrogen peroxide production and was able to inhibit the growth of P. aeruginosa and E. faecalis by its lactic acid content.Conclusion:This study explains a simple, selective, and fully validated procedure for the determination of lactic acid from probiotic bacteria.

High performance liquid chromatography (HPLC) and ultrahigh performance liquid chromatography (UHPLC or UPLC) have been the most widely used tools for research and routine quality control of active pharmaceutical ingredients (API). The most important challenge in these techniques is fast and efficient separation. Both techniques are preferred due to their selectivity, high accuracy and remarkable precision. On the other hand, they have some limitations: In some cases, traditional HPLC uses high amounts of organic solvents with longer analysis time, and furthermore UHPLC has high back pressure and frictional heating. To overcome these limitations, scientists have developed new type of column particles. In general, two different silica types of column packing material based on their backbone have been used for HPLC and UHPLC. Stationary phases that have fully porous silica particles comply with the essential criteria of analysis, but these show all the limitations of HPLC. However, in recent years, core–shell silica particles (a combination of solid core and porous shell) have been increasingly used for highly efficient separation with reduced run times. Thus, core–shell technology provides the same efficient separations as the sub 2 µm particles that are used in UHPLC, while eliminating the disadvantages (potentially lower backpressure). The key factors for core–shell particles are size and thickness of porous shell layer, the latter of which can be explained using the Van Deemter equation. The columns packed with core–shell particles have been employed in a wide range of applications for analysis and quality control of pharmaceutical active substances. This review will underline the advantages of core–shell silica particles in the analysis of pharmaceutically active ingredients based on liquid chromatography from the perspective of column properties, system suitability test parameter results and validation steps.

Background and objectives:Total anomalous pulmonary venous connection is a rare cyanotic CHD that requires surgical repair. An unligated vertical vein after total anomalous pulmonary venous connection surgery may help to decrease the episodes of post-operative pulmonary hypertensive crises, low cardiac output syndrome, and mortality. The aim was to assess long-term outcome and our post-operative transcatheter vertical vein closure experiences in five patients with repaired total anomalous pulmonary venous connection patients.Methods:A retrospective study was conducted in five cases with an unligated vertical vein following repair of supra-cardiac total anomalous pulmonary venous connection at our hospital from 2011 through 2018. Patients characteristics, cardiac catheterisation findings, surgical, and transcatheter procedural details were retrospectively analysed.Results:Transcatheter closure of the unligated vertical vein was technically successful in all the patients. Procedure-related complications were not observed in any of the patients. No long-term complication was found.Conclusions:We suggest that transcatheter closure of the patent vertical vein is an effective and well-tolerated alternative to the surgical approach.

In a recent study, opposite enantiomer elution order was observed for ketoprofen enantiomers on two amylose-phenylcarbamate-based chiral columns with the same chemical composition of the chiral selector but in one case with coated while in the other with an immobilized chiral selector. In the present study, the influence of this uncommon effect on method validation parameters for the determination of minor enantiomeric impurity in dexketoprofen was studied. The validated methods with two alternative elution orders for enantiomers were applied for the evaluation of enantiomeric impurity in six marketed dexketoprofen formulations from various vendors. In most of these formulations except one the content of enantiomeric impurity exceeded 0.1% (w/w).

Background:Psoriasis is a chronic inflammatory, multi-system disease that often begins in childhood and characterised by inflammatory skin, nails, scalp, and joint manifestations. The inflammation in psoriasis may promote some effect on the cardiac conduction system.Objective:The aim of this study is to investigate myocardial repolarisation anomaly on the conducting system in the paediatric psoriasis using P wave dispersion, Tpeak–Tend interval, and Tp-e/QT ratio.Methods:Forty-two patients diagnosed with psoriasis and 37 age- and sex-matched healthy children were enrolled in the study. Electrocardiographic parameters in psoriasis and control group were recorded from an electrocardiogram for each patient.Results:The results indicated that the parameters including Pdis, QTc dis, Tp-e dis interval, and Tp-e max/QTmax ratios, which are known to be key indicators for the prediction of severe atrial or ventricular arrhythmia and sudden cardiac death and also important parameters used as the indicators for the non-invasive evaluation of the transmural heterogeneity were significantly longer in the study group compared to the control group (p < 0.05).Conclusions:This study includes the evidence linking psoriasis with increased myocardial repolarisation heterogeneity. These findings suggest that this patient population may be at an increased risk for arrhythmias. Our findings may be a basis for further studies.

While the amino acids, enzymes and hormones are chiral, chirality plays significant role in the life of plants, animals, as well as the human being. Chirality of molecules is important in various industries, such as pharmaceutical, agricultural, food, electronics, etc. Chiral drugs may have different bioavailability, distribution, biotransformation and excretion, as well as quantitatively and/or qualitatively different pharmacological or toxic properties. Enantiomerically pure chiral drugs have been increasingly developed for the pharmaceutical market due to their superiority from the viewpoints of potency and safety. This is supported by the development of new methods for enantioselective production of the chiral compounds, as well as by the capability of the enantioselective analytical methods to allow a detection and quantification of minor enantiomeric impurity in the presence of another enantiomer in a large excess. The aim of the present review is to provide a short summary of the basic principles of chiral separations on an analytical and preparative scale. In addition, some selected applications for analytical techniques, such as gas chromatography, supercritical fluid chromatography, high performance liquid chromatography, capillary electrophoresis and capillary electrochromatography for the separation of enantiomers of chiral pharmaceuticals published in the last two years are also discussed.

The affinity pattern of terbutaline enantiomers towards various cyclodextrins was studied using capillary electrophoresis. The affinity pattern of terbutaline enantiomers was the same towards all studied cyclodextrins except heptakis(2-O-methyl-3,6-di-O-sulfo)-β-CD. Nuclear magnetic resonance spectroscopy was used for understanding of fine structural mechanisms of interactions of β-cyclodextrin and its two sulfated derivatives with the enantiomers of terbutaline. The structure of terbutaline complexes with all 3 cyclodextrins studied was different from each other. In confirmation with our earlier studies it was shown again that capillary electrophoresis represents very sensitive technique for studies of affinity patterns in cyclodextrin complexes with chiral guests. Other instrumental (e.g. NMR spectroscopy and X-ray diffraction analysis) and theoretical techniques, although very useful for obtaining the information regarding the stoichiometry, binding constants and structure of intermolecular complexes, as well as about the forces involved in selector-selectand binding and chiral recognition, may sometimes fail to properly sense those fine differences in the affinity patterns. Therefore, it is recommended to use capillary electrophoresis in order to examine correctness of affinity pattern determined for intermolecular complexes of cyclodextrins with guest molecules by other instrumental or computation techniques.

The aim of this study was to investigate the effects of extracts and pure Artemisia dracunculus L. (tarragon) metabolites on the antimonoamine oxidase and anticholinesterase activities. The compounds were characterized as stigmasterol (1), herniarin (2), (2E,4E)-1-(piperidin-1-yl) undeca-2,4-diene-8,10-diyn-1-one (3), (2E,4E)-N-isobutyl undeca-2,4-Bien-8,10-diynamide (4), 3,4-dehydroherniarin (5) and skimmin (6) by H-1-NMR, C-13-NMR, 1D and 2D NMR methods. The compounds 5 and 6 were isolated from tarragon for the first time. The extracts and pure compounds have inhibitory effects on the human monoamine oxidase (hMAO) A and B enzymes, whereas they did not exhibit any anticholinesterase activities. Among the tarragon compounds, only 2 and 6 compounds showed the inhibitory effects against hMAO A (IC50 = 51.76 and 73.47 mu M, respectively) and hMAO B (IC50 = 0.84 and 1.63 mM, respectively). In the study, herniarin content in the extracts was also analysed by high-performance liquid chromatography and it was found that there was a relationship between the inhibition effects of the extracts and their herniarin content., Agri Ibrahim Cecen University [BAP: ECZF.18.002, BAP: FEF.18.003], This study was supported by grants of Agri Ibrahim Cecen University Research Fund (BAP: ECZF.18.002 and BAP: FEF.18.003).

Objective: The objective of this study is to evaluate if echocardiographic examination causes any pain response in term and preterm infants.Methods: Term and preterm neonates who admitted to Neonatal Intensive Care Unit at Gazi University Hospital and Etlik Zubeyde Hanim Training and Research Hospital and were performed echocardiography for any reason were included into the study. Neonates were evaluated before, during and 10minutes after the examination. Vital signs (heart rate, respiratory rate, blood pressure, transcutaneous oxygen saturation) were recorded. All subjects were also evaluated with Neonatal Infant Pain Scale during the examination.Results: In this study, we evaluated 99 newborn infants. Five infants who received fentanyl treatment were excluded. The heart rate (p=0.000), respiratory rate (p=0.000), diastolic blood pressure (p=0.001) and oxygen saturation (p=0.000) during the examination were significantly different than the values before and 10minutes after the examination. Infants whose gestational age 32 weeks (n:20) have significantly higher NIPS scores (meanSEM=3.3 +/- 0.4) than the infants whose gestational age is greater than 32 weeks (n:71) (mean +/- SEM=2.4 +/- 0.2).Conclusions: Echocardiographic examination which is known as noninvasive and painless causes significant pain in preterm infants.

The major goal of this study was to determine the affinity pattern of brombuterol (BB) enantiomers toward various cyclodextrins (CD) and to evaluate the potential of NMR spectroscopy for understanding fine mechanisms of interactions between CDs and BB enantiomers. Separation of BB enantiomers was performed in a fused-silica capillary using a phosphate buffer, pH 2.5, at the room temperature in the normal polarity mode. It was shown once again that CE in combination with NMR spectroscopy represents a very sensitive tool for studies of affinity patterns and structure of CD complexes with chiral guests. Although opposite affinity patterns of BB enantiomers were observed toward native β- and γ-CDs, no significant differences between the structures of the complexes of these two CDs with BB were detected by NMR spectroscopy. In contrary to this, the opposite affinity pattern of BB enantiomers toward β-CD and its two sulfated derivatives, heptakis (2,3-O-diacetyl-6-sulfo)-β-CD (HDAS-β-CD) and heptakis (2-O-methyl-3,6-di-O-sulfo)-β-CD (HMDS-β-CD) was associated with major differences in the structure of the complexes. In addition, it was shown again that HMDS-β-CD provides separation of enantiomers without formation of inclusion-type complex with the chiral analyte.

In this study separation of enantiomers of 8 chiral ?-agonists were studied on 6 polysaccharide-based chiral columns in polar-organic and alcohol-hydrocarbon mobile phases. No separation of enantiomers was observed on any column with polar-organic mobile phase eluents such as pure methanol, ethanol or acetonitrile. Most of the chiral analytes were resolved into enantiomers when alcohol-hydrocarbon type mobile phases were used. The most successful column was Lux Cellulose-2 on which all 8 chiral analytes were baseline resolved into enantiomers at least with one mobile phase used. The reversal of enantiomer elution order was observed dependent on the chemistry of the chiral selector and the composition of the mobile phase. © 2016 Elsevier B.V.

Capillary electrophoretic (CE) and high performance liquid chromatographic (HPLC) methods were developed and optimized for the determination of antazoline (ANT) and tetrahydrozoline (TET) in ophthalmic formulations. Optimum electrophoretic conditions were achieved using a background electrolyte of 20mM phosphate buffer at pH 7.0, a capillary temperature of 25°C, a separation voltage of 22 kV and a pressure injection of the sample at 50 mbar for 17s. HPLC analysis was performed with Kinetex (150 × 4.6mm ID × 5 μm) (Phenomenex, USA) analytical column with 1 mL min(-1) flow rate of mobile phase which consisted of 0.05% TFA in bidistilled water (pH adjusted to 3.0 with 5M NaOH) and acetonitrile/buffer in the ratio of 63:37 (v/v) at room temperature. Injection volume of the samples was 10 μL and the wavelength of the detector was set at 215 nm for monitoring both analytes. Calibration graphs showed a good linearity with a coefficient of determination (R(2)) of at least 0.998 for both methods. Intraday and interday precision (expressed as RSD%) were lower than 2.8% for CE and 0.92% for HPLC. The developed methods were demonstrated to be simple and rapid for the determination of ANT and TET in ophthalmic solutions providing recoveries in the range between 97.9 and 102.70% for CE and HPLC.

A selective and sensitive stability indicting HPLC method was developed for the analysis of enantiomers of miconazole. For this purpose, six different polysaccharide-based chiral columns were evaluated. Optimization was performed using several polar organic and alcohol-hydrocarbon mobile phases. As a result of optimization studies, the analysis was carried out using Lux Cellulose-3, methanol as a mobile phase at a flow rate of 1 mL·min-1 , and the detection wavelength was arranged to 230 nm. Developed method has been fully validated according to International Council on Harmonization guidelines. Method was found linear in the concentration range of 1 to 200 μg·mL-1 . Coefficient of determination (R2 ) was calculated as 0.9996, intraday precision of the method was found with the RSD% of 0.56, and the recovery of the method was calculated close to 100%. Furthermore, some other validation parameters like specificity, selectivity, LOD, and LOQ were also investigated. Stability indicating capability of this method was shown by forced degradation studies, and the run time for each analysis was less than 6 minutes. As a result, simple, fast, reliable HPLC method was developed for the separation and determination of the enantiomers of miconazole. Applicability of the developed method was shown with the application of marketed pharmaceutical preparations.

Our earlier studies have demonstrated the applicability of polysaccharide-based chiral selectors in combination with superficially porous (or core-shell) silica (SPS) particles for the preparation of highly efficient chiral stationary phases (CSP). In earlier studies, CSPs were prepared by coating (adsorption) of the chiral selector onto the surface of silica. In this study we report for the first time the CSP obtained by covalent immobilization of a chiral selector onto the surface of SPS particles. The applicability of this CSP for the separation of enantiomers in pure methanol and acetonitrile, as well as in n-hexane/2-propanol mobile phases is shown. The effect of the injected sample amount, mobile phase flow rate and detection frequency on separation performance were studied, as well as high efficiency separation of enantiomers with the analysis time less than 30 s was attempted. (C) 2018 Elsevier B.V. All rights reserved.

In the past decades, patients who have chemotherapy treatment have considerably increased number. At this point, the development of rapid precise, and reliable methods are very important to analyze cancer drugs from their dosage forms, animals or human biological samples. Among all the analytical methods, electrochemical methods hold an important position with their unique properties such as specificity in the biological recognition process, fast response, and their reliability and do not need a pretreatment process. Chromatographic methods are also used in a wide range of analytical applications for the analyses of anticancer drugs. The power of chromatography comes from its ability to separate a mixture of analytes and determination of their concentrations. Chromatographic techniques can mainly be divided into gas, liquid, and supercritical fluid chromatography. In the frame of this information, this review is aimed to provide basic principles of electroanalytical and high-performance liquid chromatography methods for the analysis of cancer drugs. In addition, some selected applications for electrochemistry-related techniques and high-performance liquid chromatography, for the determination of anti-cancer pharmaceuticals published in the last five years are also discussed. © 2018, © 2018 Taylor & Francis Group, LLC.

This is the first report in literature using hydrophilic interaction liquid chromatography (HILIC) in combination with diode array detector (DAD) for stability indicating determination of 5-Fluorouracil (5-FU) from its bulk form, pharmaceutical preparations, developed solid lipid nanoparticle (SLN) and nano structured lipid carrier (NLC) drug delivery systems as well as the rat skin extracts. The separation was performed at 45 °C, on Sequant Zic HILIC (250 mm × 4.60 mm ID, 5 μm, 200 Ao), peek HPLC column. Mobile phase is consisting of a mixture of acetonitrile: buffer containing 5 mM ammonium acetate (95:5; v/v). The pH of the mobile phase was adjusted to 7.0 using 1 M NaOH. The analysis was carried out at 0.75 mL min?1 flow rate with a detection wavelength of 265 nm and the injection volume was arranged as 10 μL. The developed method was fully validated in accordance with the International Council on Harmonization (ICH) Guidelines. Specificity of this method was demonstrated by forced degradation studies. As a result of calibration studies, the calibration curve was found linear in the concentration range of 1–250 μg mL-1 (R2 = 0.999). The precision of this technique calculated within the frame of intra-day and inter-day based on a percentage of relative standard deviation (RSD%) values (

Dermal drug application is commonly used for the local treatment of skin diseases. However, the uppermost layer of the skin, stratum corneum, plays an effective role as a physical barrier against to the penetration of compounds into skin. The physicochemical properties of the active agents and vehicles are major limiting factors for the skin penetration of the drugs. In recent years, nanoparticulate drug delivery systems, especially lipid nanoparticles, attract considerable interest in providing enhanced skin penetration and to ensure site-specific skin targeting of drugs. Solid-lipid nanoparticles, nanostructured lipid carriers and lipid nanocapsules are manufactured using biocompatible and biodegradable lipids that have various advantages for dermal administration, such as controlled release of active agents, increasing the chemical stability of sensitive drugs, enhancing the penetrated amount of active substances into skin, and drug targeting to different skin layers. In this chapter, an overview of lipid-based nanoparticles as dermal drug delivery systems will be presented, preparation techniques and in vitro/in vivo characterization methods of lipid nanoparticles and their assays will be reviewed. Analytical studies related to the drug-loaded lipid nanoparticles, their characterization, and quantitation are also discussed and summarized as details.

Studies conducted in recent years show that pathogen bacteria are not asocial assets and they use the cell to cell communication mechanism called quorum sensing that depends on population density to adapt changing environmental conditions. This mechanism is coordinate gene expression of various bacterial factors like bioluminescence, antibiotic biosynthesis, plasmid conjugation and virulence. Bacteria communicate with each other by producing signal molecules and regulate the production of virulence factors that have importance in the pathogenity formation. Virulence mechanisms of Pseudomonas aeruginosa, which causes various types of infections in humans, are also regulated by quorum sensing. Nowadays, biotechnological researches are focused on the development of homoserine lactone antagonists. The use of these type of molecules are considered to be a new treatment approach for blocking communication between bacteria and reducing virulence, therefore improving infection control. In this study, lactic acid of a potential probiotic Pediococcus acidilactici M7 strain isolated from newborn faeces was used to evaluate the inhibitory effect on quorum sensing signal molecules and some virulence factors of clinical Pseudomonas aeruginosa isolates. Results showed that lactic acid has an inhibitory effect on short-chain HSL production and swarming-swimming-twitching motility, elastase, protease, pyocyanin, and biofilm production of Pseudomonas aeruginosa isolates in certain quantities that are regulated by the quorum sensing system.

The aim of this study was to increase rhamnolipid production by formulating media using kefir and fish meal for Pseudomonas aeruginosa strains isolated from different environmental resources. The strains, named as H1, SY1, and ST1, capable of rhamnolipid production were isolated from soil contaminated with wastes originating from olive and fish oil factories. Additionally, P. aeruginosa ATCC 9027 strain, which is known as rhamnolipid producer, was included in the study. Initially, rhamnolipid production by the strains was determined in Mineral Salt Medium (MSM) and then in media prepared by using kefir and fish meal. The obtained rhamnolipids were purified and quantified according to Dubois et al. (1956). The quantity of rhamnolipids of ATCC, H1 and SY1 strains in kefir media were determined as 11.7 g/L, 10.8 g/L and 3.2 g/L, respectively, and in fish meal media as 12.3 g/L, 9.3 g/L and 10.3 g/L, respectively. In addition, effect of UV light exposure on rhamnolipid production was also investigated but contrary a decrease was observed. The results indicate that P. aeruginosa strains isolated from various environmental resources used in this study can be important due to their rhamnolipid yield, and fish meal, which is obtained from waste of fish, can be an alternative source in low cost rhamnolipid production.

Vitamin D–deficient rickets is still an important and common health problem in developing countries. Since calcium is an essential ion for cardiac muscle contraction, calcium deficiency caused by rickets can cause secondary dilated cardiomyopathy. This situation can be exacerbated by coexisting hypomagnesemia. Here, we report a case of dilated cardiomyopathy due to hypocalcemia induced by vitamin D–deficient rickets and accompanying primary hypomagnesemia in an infant whose cardiomyopathy was successfully treated by replacement of calcium, vitamin D, and magnesium. In addition to genetic causes, viral infections, and idiopathic factors, metabolic abnormalities are important etiologic factors in pathogenesis of dilated cardiomyopathy and since they are treatable, prompt diagnosis of these disorders is crucial.

Milk has been used to produce fermented milk products all over the world since 10,000 BC. The fermentation process extends the shelf life of milk-based products. Transforming milk to different fermented foods (kefir, yogurt, etc.) involves adding lactic-acid-producing microorganisms, which ingest lactose and release waste organic acids. Organic acid refers to organic compounds that give a characteristic quality to foods as a result of hydrolysis and microbial activity of proteins and carbohydrates that have been widely used as food additives to prevent deterioration and extend shelf life. Determination of carbohydrates and organic acids in dairy fermented products is important, since they affect the characteristics of food. It is also important to determine bacterial activity, as well as the growth of the colonies. An early investigation of fermented products based on titration methods that are not selective. Otherwise these methods are not sufficient to detect low concentration of acids. To avoid these difficulties, separation techniques, such as high-performance liquid chromatography (HPLC), and gas chromatography (GC), electrodriven techniques like capillary electrophoresis (CE), and so forth, were chosen due to accurate, selective, and sensitive analysis. In this chapter, the place and the importance of separation techniques, especially HPLC for the determination of dairy products, are explained briefly and the published papers on analysis conditions, the sample preparation, and the parameters for validation are summarized.

The present investigation was aimed at optimizing Fulvestrant (FLV)-loaded nanoparticulate formulations to overcome side effects caused by the intramuscular injection of FLV, and to prolong local intra-tumoral action at high drug concentration. Novel poly(ethylene glycol) (PEG) conjugated poly(ethylene glycol)-block-poly(lactide-co-glycolide) (PEG-b-PLGA), and poly(ethylene glycol)-block-poly(epsilon-caprolactone) (PEG-b-PCL) nanoparticles were used as the drug-loading vehicles. The influence of hydrophobicity of the two different polymeric materials based nanoparticles was investigated with respect to in vitro properties, cytotoxic capacity and cell uptake potency. The sphere-shaped nanoparticles ranged between 84.56 and 220.20 nm, had negative surface charges, and exhibited sustained release profiles. In vitro cytotoxicity results demonstrated that nanoparticles prepared with the higher hydrophilic form of PEG-b-PCL, a diblock copolymer composition, exerted the highest inhibitory effect on the proliferation of MCF-7 cells and significantly increased the intracellular uptake, compared to free FLV and the other tested polymer-based formulations. The final data of this research indicated that polymer hydrophobicity was a key to improving the major characteristics, especially anti-proliferative activity of the developed polymer-based nanoparticles. The drug delivery systems formulated here are promising nanocarriers for FLV delivery and have potential for the treatment of hormone-dependent breast cancers. (C) 2017 Elsevier B.V. All rights reserved.

Cancer is the primary leading cause of mortality in the world. The key of a successful cancer treatment depends on many important parameters, such as the application route, anticancer compound, and dosage form. Among the administration routes, oral application is the most widely used application method. However, oral administration of many molecules as conventional dosage forms is limited due to a major problem-low bioavailability. Nanoscale drug delivery systems can ensure oral administration and improve the oral bioavailability of the drugs. Determination of the chemotherapeutically active molecules from the developed nanoscale systems has an important role in the effectiveness of the nanoparticles. Chromatographic techniques, especially liquid chromatography, are very suitable and accurate ways to determine the content of a pharmaceutical ingredient and its stability in both in vitro and in vivo systems. This chapter describes the importance of lipid- and polymer-based nanoscale drug delivery technologies of the anticancer molecules and summarizes the effect and type of the nanostructures, characterization parameters, analysis parameters, such as column types and mobile phase compositions, and validation parameters. © 2017 Elsevier Inc. All rights reserved.

Introduction: Etofenamate (2-(2-hydroxyethoxy) ethyl 2-[[3-(trifluoromethyl)phenyl]amino] benzoate) (ETO) is a yellowish viscous liquid which is a nonsteroidal anti-inflammatory drug (NSAID) that has been applied topically for joint and muscular pain and soft tissue disorders. Solid lipid nanoparticles (SLNs) are colloidal drug delivery systems prepared by non-irritant and nontoxic lipids that attract great interest because of their unique features. Semisolid SLNs are novel approach for dermal application of SLNs. Aims: The aim of this study was to show the development, validation, and application of a simple, selective and reliable RP-LC method that was extensively validated for its specificity and stability-indicating properties from its forced hydrolytic, oxidative, photolytic and thermal degradation products. Materials and Methods: In addition, the proposed method presented to application of ETO from rat skin extract in according to the United States Pharmacopeia and International Council on Harmonization Guidelines. For this reason, XSelect HSS T3 XP (150 x 4.6 mm ID x 2.5µm) (Waters Corp. Milford, MA, USA) analytical column was chosen for the best resolution. Mobile phase consisted of 0.1% H3PO4 in bidistilled water (pH adjusted to 7.0 with 5M NaOH) and acetonitrile in the ratio of (40:60, v/v) with the flow rate of 1 mL.min-1. The volume of the sample solutions was injected at 10µL and the detector was set up at 285 nm. The analysis was carried out at a temperature of 45oC. Coclusion: The developed stability indicating method presented low limit of detection, low limit of quantitation and good resolution between any of interferences from both commercial formulation and developed SLN formulation from rat skin, with symmetric, pure and perfect peak homogeneity. High percentage of recovery results shows that the proposed method is free from the interferences of the commonly used excipients and additives in the formulations of the commercial product or semisolid SLN formulations and also biological derivatives. © 2017 Bentham Science Publishers.

At the present time, infectious diseases maintain the importance among the reasons of deaths in the world. The main reasons of this situation are the antibiotic resistance of bacteria and the chemical limitations on synthesis of the new antibiotic molecules. To overcome these restrictions, effective drug delivery strategies like polymeric micelles, liposomes, dendrimers, solid–lipid nanoparticles keep its novelty by different scientist. Among these delivery systems, polymer-based nanoparticles have gained much attention because they provide to target the antibiotic agents to infectious regions, and have high stability in the biological environment. From this perspective, polymer-based nanosized systems can present a promising approach for the treatment of bacterial infections and be an effective strategy to overcome the serious problems. This chapter underlines the effectiveness and in vitro/in vivo performance of various antibiotics encapsulated polymer-based nanoparticles in the treatment of infectious diseases. A collection of published papers is summarized from this perspective and comments in terms of target microorganism, advantage and activity of the developed delivery system, properties of analytical techniques for the determination of in vitro and in vivo samples with the validation parameters.

In the present study, new isocratic stability-indicating reverse phase chromatographic methods were developed using HPLC and UPLC systems for the determination of entacapone (ENT) in its pharmaceutical dosage forms. Ultra performance liquid chromatography (UPLC) using small sub-2 μm particles and high-performance liquid chromatography (HPLC) were compared for separation and determination of the ENT using Acquity HSS C18 (50 × 2.1 mm, 1.8 µm) and Xbridge C18 (150 × 4.6 mm, 5.0 µm) columns by UPLC and HPLC, respectively. When using UPLC, the run time could be reduced five fold and actually the solvent consumption decreased 10 times. The proposed UPLC method would decrease the consumption of organic solvents and reagents. The present methods were validated according to ICH guideline. All analytical procedures including sample preparation, flow rate, run time of the analytical systems were at low levels. Forced degradation studies were also performed for both compounds in bulk drug samples to demonstrate the specificity and stability-indicating comparative advantage of both methods.

One-dimensional dynamic computer simulation was employed to investigate the separation and migration order change of ketoconazole enantiomers at low pH in presence of increasing amounts of (2-hydroxypropyl)-β-cyclodextrin (OHP-β-CD). The 1:1 interaction of ketoconazole with the neutral cyclodextrin was simulated under real experimental conditions and by varying input parameters for complex mobilities and complexation constants. Simulation results obtained with experimentally determined apparent ionic mobilities, complex mobilities, and complexation constants were found to compare well with the calculated separation selectivity and experimental data. Simulation data revealed that the migration order of the ketoconazole enantiomers at low (OHP-β-CD) concentrations (i.e. below migration order inversion) is essentially determined by the difference in complexation constants and at high (OHP-β-CD) concentrations (i.e. above migration order inversion) by the difference in complex mobilities. Furthermore, simulations with complex mobilities set to zero provided data that mimic migration order and separation with the chiral selector being immobilized. For the studied CEC configuration, no migration order inversion is predicted and separations are shown to be quicker and electrophoretic transport reduced in comparison to migration in free solution. The presented data illustrate that dynamic computer simulation is a valuable tool to study electrokinetic migration and separations of enantiomers in presence of a complexing agent.

Electroanalytical methods are chosen for the sensitive analysis of pharmaceutically active compounds in their dosage forms and biological samples. Electroanalytical method validation is the process used to confirm that the determination procedure employed for a specific test is suitable for its intended use like other analytical methods. Results from electroanalytical method validation can be used to judge the quality, applicability, accuracy, reliability and