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Indacaterol, a β2 agonist prescribed for long-term management of patients with chronic obstructive pulmonary disease and asthma. In this study the first MISPE cartridges was developed using indacaterol as a template for its selective extraction from rat lung tissues, enabling precise pharmacokinetic evaluation at the drug's site of action. A molecular imprinting polymer was synthesized using indacaterol as a template, methacrylic acid as a functional monomer and ethylene glycol dimethacrylate as a cross-linker with a molar ratio (1: 4: 20). The polymer was characterized by a high binding capacity of 9840 ± 0.86 and high selectivity with an imprinting factor of 4.53 ± 0.12. The synthesized polymer was utilized as a sorbent in solid-phase extraction to purify and extract indacaterol from lung tissue matrix. The optimum molecularly imprinted solid-phase extraction (MISPE) conditions were 20.0 mg of molecular imprinting polymer and non-imprinting polymer, acetonitrile as the loading solvent, acetonitrile: water (20: 80; by volume) as the washing solvent, and methanol: acetic acid (90: 10; by volume) as the eluting solvent. A pharmacokinetic study was performed for indacaterol in rat lungs using the synthesized and optimized MISPE cartridge as a tool for sample purification. These parameters were determined in the lung tissues of rats emphasizing the local exposure of indacaterol to its target organ. The Cmax and Tmax were 51.020 ± 2.810 µg mL− 1 and 0.083 ± 0.001 h, respectively. The AUC 0−24 and AUC0 − inf were 175.920 ± 1.053 and 542.000 ± 5.245 µg h mL− 1, respectively. The elimination rate constant was 0.014 ± 0.00012 h− 1 and the half-life time was 48.510 ± 0.012 h. This study successfully developed and optimized MISPE cartridges using indacaterol as a template, enabling precise pharmacokinetic evaluation in rat lung tissues. The cartridges demonstrated high binding capacity and selectivity, providing crucial insights into the local exposure of indacaterol at its site of action. [ABSTRACT FROM AUTHOR]

With the escalating demand for Astragalus polysaccharides products developed from Radix Astragali (RA), the necessity for quality control of polysaccharides in RA has become increasingly urgent. In this study, a specific method for the simultaneous determination of seven monosaccharides in polysaccharides extracted from Radix Astragali (RA) has been developed and validated using ultra-performance liquid chromatography equipped with an ultraviolet detector (UHPLC-UV) for the first time. The 1-phenyl-3-methyl-5-pyrazolone (PMP) derivatizations were separated on a C18 column (Waters ACQUITYTM, Milfor, MA, USA, 1.8 µm, 2.1 × 100 mm) using gradient elution with a binary system of 5 mm ammonium formate (0.1% formic acid)-acetonitrile for 24 min. Additionally, seven monosaccharides showed good linear relationships (R2, 0.9971–0.9995), adequate precision (RSD < 4.21%), and high recoveries (RSD < 4.70%). The established method was used to analyze 109 batches of RA. Results showed that the Astragalus polysaccharides (APSs) mainly consist of mannose (Man), rhamnose (Rha), glucose (Glu), galactose (Gal), arabinose (Ara), xylose (Xyl); and fucose (Fuc); however, their composition was different among RA samples from different growth patterns, species, growth years, and origins, and the growth mode of RA and the age of wild-simulated RA can be accurately distinguished by principal component analysis (PCA). In addition, the immunological activity of APSs were also evaluated jointly by measurement of the NO release with RAW264.7, with the results showing that APSs have a promoting effect on the release of NO and exhibit a significant correlation with Man, Glu, Xyl, and Fuc contents. Accordingly, the new established monosaccharides analytical method and APS-immune activity determination in this study can provide a reference for quality evaluation and the establishment of quality standards for RA. [ABSTRACT FROM AUTHOR]

In the present study, a comprehensive strategy based on substances profiling in vivo and network pharmacology method was applied to screen out the potential immunomodulatory activity substances and mechanism of Wu Shen Wan. As a result, a total of 121 constituents were identified or tentatively characterized, including 26 flavonoids, 16 alkaloids, 10 tanshinones, four diterpenes, seven iridoid glycosides, eight coumarin, 18 phenolic acids, 29 ginsenosides, and three others. Moreover, 57 prototypes were clearly screened out in rat plasma and urine after ingestion of Wu Shen Wan. The Wu Shen Wan exhibited immunomodulatory effects via significantly increasing the phagocytic activity of macrophages and inducing the release of nitric oxide, tumor necrosis factor‐α, and interleukin 6 in RAW264.7 cells. In addition, the network pharmacology results showed that the top 20 Kyoto Encyclopedia of Genes and Genomes clusters were enriched, such as mitogen‐activated protein kinases pathway. This is the first systematic study on the chemical constituents of Wu Shen Wan. The analytical method features a quick and comprehensive dissection of the chemical composition and provides a basis for exploring its immunomodulatory effects. [ABSTRACT FROM AUTHOR]

The ternary mixture of doxycycline hyclate (DOX), ambroxol hydrochloride (AMB), and ambroxol synthetic precursor and process impurity (IMP) as chemically identified in the British Pharmacopeia as 2-amino-3, 5-dibromobenzaldehyde was examined for the first time using an ultra-performance liquid chromatographic technique. The presented work aimed to develop and validate a green accurate sensitive modern method for determination of this mixture. The obtained UPLC was accomplished by using an UPLC C18 column with mobile phase combination of acetonitrile: water (60:40, v/v) which was flowed at the rate of 0.22 mL per minute. Elution was in an isocratic manner and temperature control set at room temperature. UV was used to identify the effluent, which was injected at a volume of 5.00 µL; 370 nm for DOX and 240 nm for AMB and IMP. In concentration ranges; of (5–150) µg mL−1, linearity of both DOX and AMB was attained and of (0.5–40) µg mL−1, linearity of IMP was attained. Accuracy of this UPLC method was found to be 100.28, 99.66, and 100.36 for DOX, AMB, and IMP, respectively. ICH standards were followed while making the method validation. The existing combined pharmaceutical dosage form was analyzed by the obtained UPLC method for determination of the evaluated drugs successfully and the obtained results expressed as (Recovery % ± SD) were 101.02 ± 1.37 for DOX and 102.22 ± 1.56 for AMB. Also, the statistically significant correlation of our created approach to the reported HPLC method revealed no appreciable differences in terms of accuracy and precision. The developed method's greenness profile was appraised using many greenness metrics, green assessment comparison between the established columnar method and the published ones was made. [ABSTRACT FROM AUTHOR]

Hugan tablet is a Chinese medicine preparation. It is composed of Bupleuri Radix, Artemisiae Scopariae Herba, Isatidis Radix, Schisandrae Chinensis Fructus, Suis Fellis Pulvis, and Vigna radiata L. It has the effects of dispersing stagnated liver qi, strengthening the spleen and eliminating food to be used for the treatment of chronic hepatitis and early cirrhosis. However, the chemical composition of Hugan tablet is complex and not fully understood, which hampers the research in pharmacology. In this study, a reliable method for the rapid analysis and identification of the chemical components in Hugan tablet by their characteristic fragments and neutral losses using ultra‐performance liquid chromatography‐quadrupole‐exactive orbitrap mass spectrometry was developed. A total of 144 chemical components were tentatively identified, including 57 organic acids, 19 flavonoids, 23 alkaloids, 18 lignans, 7 saponins, and 20 others. These components may be the active ingredients of Hugan tablet. The established method can systematically and rapidly analyze the chemical components in Hugan tablet, which provides a basis for the pharmacodynamic substance study and is meaningful for the quality control of Hugan tablet. [ABSTRACT FROM AUTHOR]

This study dealt with determination of ochratoxin A (OTA) in roasted coffee by ultra-performance liquid chromatography and fluorescence detection (UPLC-FLD). Coffee features characteristic sensory properties, contains a wide range of beneficial substances and is among the most sold commodities worldwide. UPLC-FLD method for determination of OTA in ground roasted coffee was optimized and validated. A calibration curve of good linearity (R² > 0.999) was obtained for the range of 0.3-10 ng·ml-1, and the limit of detection and limit of quantification for OTA were 0.1 µg·kg-1 and 0.3 µg·kg-1, respectively. The recovery of certified reference material for OTA ranged between 81.3-112.8 % and the relative standard deviation under repeatibility conditions was 11.7 %. The method was applied to the analysis of OTA in coffee obtained from retail stores in Czech Republic. Sixteen samples (29 %) of roasted coffee were positive, containing OTA in the range from 0.31 µg·kg-1 to 1.06 µg·kg-1. None of the samples analysed exceeded the legislative limit according to EU Commission Regulation No. 1881/2006. [ABSTRACT FROM AUTHOR]

BACKGROUND: Sulfonamide residues in foods of animal origin are potential risks to consumer health, so it is very important to inspect them. Among the previously reported instrumental methods, the best method can only be used to determine at most 22 sulfonamides. Thus, an instrumental method capable of determining more sulfonamide species is desirable. RESULTS: In this study, sulfadoxine was used as a template to synthesize a type of magnetic molecularly imprinted polymer that could recognize 35 sulfonamides. After characterization, this composite was used to develop a dispersive solid‐phase extraction method for extraction and purification of the 35 sulfonamides in pork, followed by determination using an ultra‐performance liquid chromatography photodiode array method. This composite exhibited high adsorption capacity (11.01–19.21 μg mg−1) and high recovery (>89.01%), and could be reused at least ten times. Due to the enrichment effect during sample preparation (enrichment factor 22–66), the limits of detection for determination of the 35 drugs in pork were in the range of 0.08–0.53 ng g−1. The detection results for some real pork samples were consistent with a liquid chromatographic–tandem mass spectrometric method. After comparison, the present method showed generally better performances than the previously reported sample preparation methods and instrumental methods for detection of sulfonamides. CONCLUSION: The method developed in the present study could be used as a practical tool for routine detection of sulfonamide residues in pork samples. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Chirality plays a vital role in the lives of humans, plants, and animals because various proteins, amino acids, hormones, enzymes are chiral in nature. It is important in different areas such as agriculture, medicine, food, and chemical industries. Chiral compounds may have varying pharmacodynamic and pharmacokinetic parameters, as well as pharmacological and toxic characteristics. Because of their advantages in terms of potency and safety, enantiomerically pure chiral compounds are increasingly being developed by the pharmaceutical industry. This is reinforced by the development of novel methods for enantioselective chiral chemical synthesis as well as the ability of enantioselective analytical methods to identify and quantify small enantiomeric impurities in the presence of a significant excess of another enantiomer. This work aims to offer a short overview on the essential principle of chiral separations on a quantitative scale through this article. In addition, this article includes various types of chiral stationary phases and their applications. Furthermore, gas and liquid chromatography are also discussed as analytical methods used for the separation of chiral compounds. [ABSTRACT FROM AUTHOR]

There is an increased need for the sensitive and accurate measurement of estradiol levels in patients with estradiol-related endocrine disorders. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is a reliable and accurate method for measuring steroid hormone levels. Here, we aimed to establish an LC-MS/MS-based method to quantify estradiol levels without sample derivatization and evaluated its analytical performance. Sciex Triple Quad 6500 + LC-MS/MS was used for estradiol analysis. We evaluated its analytical performance, including linearity, precision, the lower limit of detection and quantification (LoD and LoQ, respectively), accuracy, and carryover. The estradiol results determined by LC-MS/MS were compared with those obtained using a chemiluminescent microparticle immunoassay. The LC-MS/MS output was linear for serum estradiol concentrations in the range of 0.2–10311.6 pmol/L. The intra-laboratory precision (coefficient of variation) was 3.0–10.1 %. The LoD and LoQ were 2.8 and 7.5 pmol/L, respectively. The overall accuracy was within 15 % of bias, and the carryover was within the acceptable range (<1.0 %). The results of the estradiol analysis determined by LC-MS/MS were comparable to those obtained by the chemiluminescent microparticle immunoassay (r2 = 0.9843), although there was a negative bias of − 17.82 (95 % confidence interval, −27.21 to − 8.44). A highly sensitive, derivatization-free LC-MS/MS method was successfully developed in this study. This may be beneficial for estradiol measurements in patients with estradiol-related endocrine disorders. [ABSTRACT FROM AUTHOR]

Classical and chemometric calibration strategies based‐Ultra Performance Liquid Chromatography‐Photodiode Array (UPLC‐PDA) measurements were improved to monitor the in‐vitro dissolution profiles of lamivudine (LAM) and zidovudine (ZID) in tablets and to quantify drugs. To generate UPLC‐PDA data, UPLC analysis was done using the mobile phase containing acetonitrile‐acetate buffer pH 5.0 (18 : 82, v/v). In the classical strategy, calibration curves were obtained by using the peak area ratios detected at 274 nm for LAM and 268 nm for ZID, respectively. Principal component regression (PCR) and partial least squares (PLS) strategies were used to solve the same problem using UPLC‐PDA measurements obtained at eight different wavelengths. Both classical and chemometric approaches were successfully applied for drugs assay and in‐vitro dissolution testing. Assay results showed that the proposed chemometric tools gave better results because they helped to minimize the effect of chromatographic issues that commonly occur with the classical UPLC approach, such as the higher standard deviation of the assay results. [ABSTRACT FROM AUTHOR]

Gaucher disease is a rare inherited disorder caused by a deficiency of the lysosomal acid beta-glucocerebrosidase enzyme. Metabolomic studies by our group targeted several new potential urinary biomarkers. Apart from lyso-Gb1, these studies highlighted lyso-Gb1 analogs −28, −26, −12 (A/B), +2, +14, +16 (A/B), +30, and +32 Da, and polycyclic lyso-Gb1 analogs 362, 366, 390, and 394 Da. The main objective of the current study was to develop and validate a robust UPLC-MS/MS method to study the urine distribution of these biomarkers in patients. Method: Urine samples were purified using solid-phase extraction. A 12 min UPLC-MS/MS method was developed. Results: Validation assays revealed high precision and accuracy for creatinine and lyso-Gb1. Most lyso-Gb1 analogs had good recovery rates and high intra- and interday precision assays. Biomarker-estimated LOD and LOQ levels ranged from 56–109 pM to 186–354 pM, respectively. Comparison between GD patients and healthy controls showed significant differences in most biomarker levels. Typically, treated GD patients presented lower biomarker levels compared to untreated patients. Conclusions: These data suggest that the metabolites investigated might be interesting GD biomarkers. More studies with a larger cohort of patients will be needed to better understand the clinical significance of these GD biomarkers. [ABSTRACT FROM AUTHOR]

A graphitic carbon nitride was synthesised and nalidixic acid (NA) based molecularly imprinted microspheres (MIMs) were polymerised on its surface to create a composite material. After characterisation and evaluation of its absorption ability, the composite was used to prepare a solid-phase extraction (SPE) cartridge for purification of fluoroquinolones in chicken muscle, analysed by ultra-performance liquid chromatography. The cartridge showed high absorption capacities (378–559 μg) and high recoveries (92.1–99.4%) for eight fluoroquinolones, and could be reused at least 20 times. The limits of detection for the 8 drugs were 0.2–0.8 ng g−1, and recoveries from standard fortified blank chicken muscle samples were 71.9–96.8%. This is the first study reporting the use of molecularly imprinted graphitic carbon nitride composite to determine the residue of veterinary drug in foods of animal origin. [ABSTRACT FROM AUTHOR]

Pruni Semen, the dried ripe seed of Prunus humilis , P. japonica , or P. pedunculata as recorded in the Chinese Pharmacopoeia, has been widely used in pharmaceutical and food industries. The adulteration of the marketed product with morphologically similar plants of the same genus has led to variable product quality and clinical effectiveness. This study systematically investigated the phylogenetic relationships, morphological traits, and chemical profiles of 37 Pruni Semen samples from planting bases, markets, and fields. DNA barcoding could successfully distinguish the genuine and counterfeit Pruni Semen, and the results indicated that there was almost no authentic Pruni Semen available in the market. The samples were divided into "big seed" (P. pedunculata and P. salicina seeds) and "small seed" (P. humilis , P. japonica, P. tomentosa, and P. avium seeds) categories based on morphology results. The notable discrepancy in the chemical characteristics of "big seed" and "small seed" was that "small seeds" were rich in flavonoids and low in amygdalin, whereas "big seeds" were the opposite. Furthermore, principal component analysis and clustered heatmap analysis verified the distinguishing features of "big seed" and "small seed" based on morphological and chemical characteristics. This study suggested that a combination of DNA barcoding and morphological and chemical characteristics can aid in the identification and quality evaluation of authentic and adulterated Pruni Semen. These findings may help standardize Pruni Semen available in the market and protect the rights and interests of customers. [Display omitted] • Pruni Semen is often adulterated with morphologically similar plants. • Authentic samples were identified and evaluated using DNA barcoding, morphology, and chemical analysis. • No authentic Pruni Semen could be identified in the market. • P. humilis and P. japonica were rich in flavonoids and low in amygdalin, whereas P. pedunculata were the opposite. • Multiforin A was suggested to be used as a quality control indicator for Pruni Semen. [ABSTRACT FROM AUTHOR]

Climate change significantly affects the suitability distributions of natural populations , especially relict species such as Eucommia ulmoides Oliv. (E. ulmoides). However, the driving eco-factors of the distribution of E. ulmoides and the relationship between geo-distribution patterns and quality are still unclear. Here, a new approach was established by combining machine learning models (MaxEnt, Random Forest, and Biomod2 model), ultra-performance liquid chromatography (UPLC) and spatial analysis to address this question. The results reveal that temperature is the most critical variable influencing the distribution of E. ulmoides including Bio1, Bio10, and Bio11, followed by precipitation. Multi-model predictions of suitable habitats for E. ulmoides cover an area ranging from 113.33 × 104 km2 to 285.98 × 104 km2, mainly distributed in the mountainous areas of southwestern China, including the eastern regions of the Dalou, Wuling, and Qinling-Daba Mountains. Under different future scenarios, suitable habitat shifted northward by 184.90–424.88 km, and the contraction area is greater than the expansion area, with the difference ranging from 49.28 × 104 km2 to 98.39 × 104 km2. Eight common components (e.g., chlorogenic acid and pinoresinol doglucoside) and two endemic components (caffeic acid and geniposidic acid) were found in the leaves of the northern and southern medicinal districts (SDM and NMD). The contents of eight key secondary metabolites of E. ulmoides leaves were better distributed in SDM than in NDM. Among these, Xinyang in Henan, Lu'an and Fuyang in Anhui, and the southeastern region of Zhejiang are suitable growing areas for the high-quality cultivation of E. ulmoides , which deserve special attention. The seasonal precipitation (Bio15) was negatively correlated with chlorogenic acid and pinoresinol diglucoside while longitude significantly positively correlated with pinoresinol diglucoside. Overall, this study provides a novel assessment pattern for quality assessment and effective protection of E. ulmoides. [Display omitted] • Assessing the regularity of E. ulmoides geographic and quality distributions using machine learning models and UPLC methods. • Discovering 8 common medicinal components and 2 unique compounds in E.ulmoides leaves from SMD and NMD. • The precipitation seasonality and longitude are vital environmental variables affecting the accumulation of active components in leaves. [ABSTRACT FROM AUTHOR]

Antigenic peptide-loaded cationic liposomes have shown promise as cancer vaccines. Quantification of both peptides and lipids is critical for quality control of such vaccines for clinical translation. In this work we describe a reversed phase ultra-performance liquid chromatography (RP-UPLC) method that separates lipids (DOTAP, DOPC and their degradation products) and two physicochemically different peptides within 12 min. Samples were prepared by dilution in a 1:1 (v/v) mixture of methanol and water. Peptide quantification was done via UV detection and lipids were quantified by an evaporative light scattering detector (ELSD), both coupled to the RP-UPLC system, with high precision (RSD < 3.5%). We showed that the presence of lipids and peptides did not mutually influence their quantification. Limit of detection (LOD) and limit of quantification (LOQ), as determined in the ICH guidelines, were 6 and 20 ng for DOTAP, 12 ng and 40 ng for DOPC, 3.0 ng and 8.0 ng for peptide A and 2.4 ng and 7.2 ng for the more hydrophobic peptide B. Finally, lipid degradation of DOTAP and DOPC was monitored in peptide loaded DOTAP:DOPC liposomes upon storage at 4 °C and 40 °C. [ABSTRACT FROM AUTHOR]

Soil is useful physical evidence for linking a suspect/victim to a particular crime scene. However, the discrimination of soils from neighboring locations can be a very challenging task. In this work, we evaluated four row-wise manipulations (RWMs) on chromatographic data of soils for improving the discriminative ability of the data. Five red, brown, and yellowish-brown soils were collected from five nearby locations in Bangi, Malaysia. Then, the non-volatile organic compounds of soils extracted via acetonitrile were determined using an ultra-performance liquid chromatography (UPLC) system. Eventually, three sets of UPLC data were obtained at 254 nm and independently pre-processed using the four RWMs, respectively. The improvements caused by the RWMs were first derived from visual inspection on the mean chromatograms and scores plot of principal component analysis. Next, the two most desired principal components were determined using a one-way ANOVA-least significant difference test and inspected via composite box plots. Results showed that standard normal variate is the only one that caused the positive impacts though not always. Normalization to sum appeared to reduce the quality of the raw data. Hence, in conclusion, the use of RWMs on the UPLC chromatogram must be carefully evaluated. [ABSTRACT FROM AUTHOR]

The aim of this study was to develop a new simple and cost-effective spectrophotometric method to be used as an alternative to chromatography for the analysis of paracetamol and methocarbamol (PAR-MET) combination. In this regard, a comparative study on the quantitative resolution of PAR and MET mixture using continuous wavelet transform (CWT) and ultra-performance liquid chromatography (UPLC) techniques was performed. In interpretation of the spectrophotometric data, three different wavelet families Biorthogonal3.5 (Bior3.5), Mexican Hat Function (Mexh), and Symlets5 (Sym5) were found suitable to get better transform of zero-order spectra of the samples containing PAR and MET. The concentrations of PAR and MET in the working range of 4.0 – 20.0 μg/mL and 5.0 – 45.0 μg/mL, respectively, were proportional to the wavelet amplitudes. This mathematical relationship was used to construct calibration curves for each compound. After validation of the CWT method, analyses of commercial tablets were successfully performed. A new UPLC method was developed and validated in order to compare the results with those obtained by the CWT method and the data were found comparable. The analysis of results obtained from experimental trials showed that the proposed CWTmethod is suitable for the quality control and quantitative assessment of both active substances in tablet formulations. [ABSTRACT FROM AUTHOR]

Background: Therapeutic drug monitoring (TDM) of voriconazole is recommended for personalizing doses. The objective of this study was to compare the enzyme immunoassay developed by ARKTM Diagnostics Inc. for the quantification of voriconazole adapted to the Architect C4000 autoanalyzer (Abbott®) with ultra-performance liquid chromatography using ultraviolet detector (UPLC-UV) method. Materials and Methods: Linearity, precision and accuracy of both methods were validated according to the Food and Drug Administration (FDA) and European Medicines Agency guidelines. The limit of quantification (LOQ) of the UPLC-UV method was determined experimentally. Both methods were applied to the analysis of 62 samples from patients. Correlation was evaluated by Passing-Bablok analysis and the concordance by the Bland–Altman method. Dosage recommendations were generated; the discordances according to the technique were evaluated. Results: All validation parameters determined for UPLC-UV met the criteria set out and LOQ of 0.1 μg/mL was established. However, when the enzyme immunoassay was used to determine concentrations ≤1 μg/ml, CVs were >20%. A linear correlation between both methods was found. However, an overestimation of immunoassay (systematic error of 0.39 μg/mL) was detected. In 11.3% of the samples, the differences in concentrations when they were determined by different techniques would imply a different therapeutic regime. These samples had concentrations close to 1 μg/mL. Conclusion: Although both techniques can be used for TDM of voriconazole, when a value close to the lower limit of the therapeutic range is determined by the ARKTM immunoassay, it would be better to verify the result by a non-automated technique to avoid possible underdosing. [ABSTRACT FROM AUTHOR]

Tuberculosis (TB) is caused by Mycobacterium tuberculosis and is one of the primary causes of death worldwide. Rapid and accurate diagnosis of TB is one of the most direct means to reduce the incidence of TB. In this study, urinary proteomic profiling of TB patients and non‐TB individual controls (HCs) was performed, and differentially expressed urinary proteins between TB and HCs were compared and exclusively expressed proteins in TB patients were selected to establish a clinically useful disease marker panel. In total, these top 11 targeted proteins with 265 peptides were scheduled for multiple reaction monitoring validation analysis by using urine samples from 52 TB patients and 52 HCs. The result demonstrated that a three‐protein combination out of the five‐protein panel (namely P22352, Q9P121, P15151, Q13291, and Q8NDA2) exhibited sensitivity rate of 82.7% in the diagnosis of TB. Furthermore, the three‐protein combination could differentiate TB from the latent tuberculosis (LTB) effectively, which exhibited specificity rate of 92.3% for the diagnosis of TB from the LTB category. Although more numbers of clinical samples are required for further verification, the results provided preliminary evidence that this "three‐protein combination" out of the five‐protein panel could probably be a novel TB diagnostic biomarker in clinical application. [ABSTRACT FROM AUTHOR]

As chitin is gaining an increased attention as feedstock for industry, quantification thereof is becoming increasingly important. While gravimetric procedures are long, not specific and highly labour-intensive, acidic hydrolysis of chitin into glucosamine followed by quantification of the latter is more performant. Even though several quantification procedures for the determination of chitin can be found in the literature, they give inconsistent results and their accuracy was not assessed due to the lack of certified analytical standards. Therefore, in the present study, commercially available chitin from practical grade was characterised in detail, allowing the assessment of method accuracy. The procedure for the hydrolysis of chitin into glucosamine and subsequent quantification via UPLC-MS was investigated in detail as well. Using 9-fluorenylmethyl chloroformate (FMOC-Cl) as derivatisation reagent, glucosamine was quantified using reversed-phase chromatography. For the chitin hydrolysis, the highest glucosamine recovery was obtained with 8.0 M HCl for 2 h at 100 °C. The entire procedure for chitin quantification, including the hydrolysis, was characterised by high interday and intraday precision and accuracy. The specificity of the procedure was assessed as well by analysing different mixtures of cellulose and chitin. Chitin recoveries from these analyses ranged from 98.8 to 105.8% while no signal was observed for 100% cellulose, indicating the high specificity of the procedure. It was also concluded that the procedure is much faster and less labour-intensive compared to the gravimetric procedure. [ABSTRACT FROM AUTHOR]

A method is proposed for the identification of surfactants by ultra-performance liquid chromatography (UPLC) with high-resolution mass spectrometry detection after screening water and food samples for the total concentration of cationic and anionic surfactants by microextraction–fluorimetry. The method is based on the use of dispersive liquid–liquid microextraction with chloroform of surfactant ion pairs with organic reagents (eosin and acridine yellow), measuring the fluorescence of the obtained adducts using a smartphone, obtaining RGB colorimetric characteristics, and determining the total surfactant concentration. The main analytical characteristics of the identification of cationic surfactants (alkylpyrdinium, alkyltrimethylammonium, alkyldimethylbenzylammonium (benzalkonium), alkylmethylethylbenzylammonium, didecyldimethylammonium, benzyldimethyl[3-(myristoylamino)propyl]ammonium, N,N-bis(3-aminopropyl)dodecylamine chlorides) and anionic surfactants (alkyl benzene sulfonates (sulfonol), alkyl sulfates, laureth sulfates, alkyl sulfonates, and sodium alkyl carboxylates) by chromatography–mass spectrometry under the selected conditions of chromatographic separation and mass spectrometric detection are found. The features of the chromatographic behavior of the surfactant polymerhomologs under the conditions of UPLC and gradient elution are considered. [ABSTRACT FROM AUTHOR]

A novel chromatographic method, ultra-performance liquid chromatography (UPLC) was improved to determine sulfamethoxazole and trimethoprim in a two-component tablet formulation. In the implemented of the method, the chromatographic parameters were optimized by using the experimental design and optimization procedure. The central composite design and fitting model was applied to identify the suitable chromatographic conditions providing a desirable elution of sulfamethoxazole and trimethoprim in a chromatogram. In the central composite design, temperature, flow rate and buffer% were selected as the effective factors on the chromatographic resolution. The buffer system was the mixture of 0.1 M CH3COOH and CH3COONa (pH 4.75) in mobile phase system. In the optimization step, the chromatographic conditions were found to be 0.20 mL/min for flow rate, 38.0 °C for the column temperature and 66% for the acetate buffer system (v/v) in the mobile phase. Analysis of the investigated drugs was accomplished on a stationary phase based on Waters BEH C18 column (50 mm-2.1 mm, 1.7 mm i.d.). In the validation step, recovery study was performed by analyzing the synthetic binary mixture of sulfamethoxazole and trimethoprim. Recovery results were found as 99.12% for sulfamethoxazole and 99.44% for trimethoprim. Assay results showed that the optimized chromatographic technique was very suitable for the quantitation of sulfamethoxazole and trimethoprim in tablets. [ABSTRACT FROM AUTHOR]

Introduction: Andrographis paniculata contained many pharmacologically active diterpenoids. Objectives: A simple and rapid isocratic reverse phase chromatographic method was developed using UPLC for simultaneous determination of 5 diterpenoids; andrographolide, deoxyandrographiside, neoandrographolide, 14-deoxyandrographolide and 14-deoxy-11,12-didehydroandrographolide in A. paniculata capsules. Materials and Methods: The chromatographic separation was achieved on a Waters Acquity BEH C18, 50 × 2.1 mm, 1.7 µm column using mobile phase consisting of acetonitrile and water in a ratio of 25:75 (v/v). The flow rate was 0.4 ml/min with a runtime of 12 min. The method was validated according to the regulatory guidelines with respect to specificity, linearity, precision, accuracy, limit of detection, limit of quantitation and robustness. Results: The proposed method provided linear responses (r2>0.999) with good precision (%RSD<3%). The recovery values ranged from 98.00% to 101.36% for all compounds. Conclusion: A validated UPLC method for analysis of andrographolide and four bioactive analogs in A. paniculata was successfully established. The developed method was applied for analysis of 5 active compounds in capsule formulation. [ABSTRACT FROM AUTHOR]

A rapid, robust and accurate ultra-high performance liquid chromatographic method was developed and validated for determination of impurities of simvastatin in drug and its pharmaceutical formulation. A systematic Quality-by-design approach was used for method development with the Fusion AETM software, to screen and optimize the column, mobile phase, column temperature, gradient time and other chromatographic conditions. The optimized method uses Waters Acquity Charged Surface Hybrid, Octadecylsilane C18 (1.7μm×2.1 mm×100 mm) column with gradient elution. Orthophosphoric acid pH was adjusted to 4.5 with triethylamine and acetonitrile with a ratio of (80:20) was used as mobile phase A, whereas methanol:acetonitrile (20:80) as mobile phase B, with a flow rate of 0.35 ml/min. Ultra Violet detector was programmed at 238 nm with a runtime of 13 min, wherein all the impurities were well resolved and were separated from main peak of simvastatin. The method was validated for accuracy, repeatability, reproducibility and robustness. All the validation parameters were in acceptable range. The linearity, limit of detection and limit of quantitation was established for all the impurities and for simvastatin. The method was also applied suitably for determining the degradation products of simvastatin using stress degradation studies. [ABSTRACT FROM AUTHOR]

Because the conventional methods for furosine analysis are time-consuming, a modified method is presented to improve analysis efficiency. Microwave-assisted HCl hydrolysis was performed at 140, 150, and 160°C for 10 to 200 min, with 6, 8, or 9 M HCl. The hydrolysate purification process was carried out using only paper and membrane filtration. An ultra-performance liquid chromatography (UPLC) system was used to achieve rapid analysis of furosine. The results showed that microwave-assisted HCl hydrolysis at 8 M and 160°C led to a stable furosine yield and took only 40 min. The UPLC analysis was completed in 8 min. The modified method was validated and obtained limit of detection at 3 µg/L, limit of quantitation of 10 µg/L, linearity range of 0.2 to 5.0 mg/L, 80.5 to 94.2% recoveries from spiked samples, and coefficients of variation of 2.2 to 6.8%. The modified method is rapid and reliable for the determination of furosine in milk. [ABSTRACT FROM AUTHOR]

Background: Medicinal plant extracts and herbal preparations are complex mixtures of active and ballast substances, which may contain in frequently up to several hundreds of different constituents, with no exactly defined structures at which chromatography undoubtedly is a fundamental tool to overcome the challenges of these phytoanalytics. Aim of the Study: To investigate Pterocephalus frutescens aerial part extracts biologically and chemically and the correlation of biologically active constituents with their corresponding activities. Materials and Methods: Ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometer with principal component statistical analysis was used for the identification of phytoconstituents, while spectrophotometer was used for quantitative analysis and both qualitative and quantitative antioxidant effects using stable radical diphenylpicrylhydrazyl, and the cytopathic effect inhibition assay was used for antiviral screening. Results and Conclusion: P. frutescens extracts exhibited antioxidant and antiviral activities along with tentative identifying of 46 compounds from which 38 compounds were correlated with either antiviral and/or antioxidant activities, besides the quantification of phenolic, flavonoid, phenylethanoid, and iridoid contents. [ABSTRACT FROM AUTHOR]

Introduction: Sattakavata formula (SVF) is a Thai traditional medicine from Ayurved Siriraj for a relief of joint pain. It comprises six ingredients, namely, Andrographis paniculata (Burm. F.) Wall. ex Nees (AP), Cinnamomum sp. (CN), Morus alba Linn. (MA), Crateva adansonii DC. subsp. trifoliata (Roxb.) Jacobs (CA), Moringa oleifera Lam. (MO), and Acorus calamus Linn. (AC). There was no method for identification and quantification of SVF before. Objective: The objective of the study was to establish a method for identification and quantification of apigenin and quercetin in SVF and its components using ultra-performance liquid chromatography-mass spectrometry (UPLC-MS). Materials and Methods: SVF and six components were extracted with 80% ethanol by ultrasonication. The separation was performed in an RP18 column using a gradient elution with 0.1% formic acid in deionized water and acetonitrile. The method was fully validated in terms of precision, limit of detection, limit of quantification, and recovery. Results: Apigenin was found in SVF, AP, and CN, and quercetin was found in SVF, CN, and MA. There was a good linearity (R2 > 0.999) in the range of 100-1400 ng/ml for apigenin and 300-3000 ng/ml for quercetin. The recovery of apigenin and quercetin was in the range of 88.33-111.52% and 90.71-109.17%, respectively. Relative standard deviations of precision in apigenin and quercetin were 0.62-6.02 and 0.65-4.01, respectively. Conclusion: A reliable UPLC-MS method for identification and quantification of apigenin and quercetin in SVF was successfully established in this study. The method is useful in the quality control of the herbal medicines and can be used routinely. [ABSTRACT FROM AUTHOR]

An ultra-performance liquid chromatography method with ultraviolet detection was developed for the determination of related substances in rivaroxaban in active pharmaceutical ingredient. The determination of related substances in rivaroxaban is highly significant as this would tolerate more effective generation of clinical data. The chromatography analysis was performed at 30°C using a gradient mobile phase consisting of buffer (0.01 N potassium dihydrogen ortho phosphate with pH 4.8) and acetonitrile in the ratio of 50:50% (v/v) using variable wavelength ultraviolet–visible detector set at 240 nm. Rivaroxaban and related impurities (A, B, and C) were eluted in a gradient at a steady flow rate of 1.0 mL/min with retention times around 5.6 min (rivaroxaban), 2.4 min (Imp A), 8.8 min (Imp B), and 3.6 min (Imp C) with asymmetry factor 1.2 (rivaroxaban), and linearity correlation coefficients in the range of 0.25–1.5 ppm for all impurities. Regression coefficient was 0.999 for all the impurities, while recovery from samples was 96.4–98.6 % (Imp A), 96.3–96.6 % (Imp B), and 95.7– 98.5% (Imp C) for rivaroxaban impurities, respectively. Relative standard deviations of method precision were <1% for total impurities in rivaroxaban. Specificity/selectivity characteristics were established and confirmed that the absence of interference of related impurities with respect to rivaroxaban analyte peak. From the above parameters indicated that the present developed method is most precise, accurate, reproducible, and specific for the determination of rivaroxaban related impurities in drug substance for routine analysis. [ABSTRACT FROM AUTHOR]

BACKGROUND: Fungicides are often applied to pears before they are kept in storage facilities. The scientific application of pesticides can reduce unnecessary exposure, which in turn could benefit both humans and the environment. RESULTS: We investigated dissipation behavior and residue distribution, and conducted risk assessments for prochloraz, pyraclostrobin, and tebuconazole in pears stored under different conditions using ultra‐performance liquid chromatography (UPLC). The recoveries of the three fungicides ranged from 76.5% to 114.5%, and the coefficients of variation were 1.0%–8.5%. The half‐life (t1/2) ranges for degradation of the three fungicides in Dangshan Su pear peel were 8.8–13.9 days after storage at 25 °C and 99.0–346.6 days after storage at 2 °C. Among the three fungicides, tebuconazole had the lowest residue concentration in pear pulp (maximum of 0.226 mg·kg−1) and the longest half‐life (≥ 231.0 days). Accordingly, among these fungicides, tebuconazole is the most suitable for the preservation of Dangshan Su pears during storage. Finally, we analyzed samples of six pear varieties from markets in China and found that the residue concentrations of the three fungicides in pear pulp and fruit met Chinese standards. CONCLUSION: The results provide a scientific basis for rationalizing the use of prochloraz, pyraclostrobin, and tebuconazole, and improving the safety of pears for eating. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

A novel enzyme, thiourocanate hydratase, which catalyses the conversion of thiourocanic acid to 3-(5-oxo-2-thioxoimidazolidin-4-yl) propionic acid, was isolated from the ergothioneine-utilizing strain, Burkholderia sp. HME13. When the HME13 cells were cultured in medium containing ergothioneine as the sole nitrogen source, thiourocanate-metabolizing activity was detected in the crude extract from the cells. However, activity was not detected in the crude extract from HME13 cells that were cultured in Luria-Bertani medium. The gene encoding thiourocanate hydratase was cloned and expressed in Escherichia coli , and the recombinant enzyme was purified to homogeneity. The enzyme showed maximum activity at pH 7.5 and 55°C and was stable between pH 5.0 and 10.5, and at temperatures up to 45°C. The K m and V max values of thiourocanate hydratase towards thiourocanic acid were 30 μM and 7.1 μmol/min/mg, respectively. The enzyme was strongly inhibited by CuCl2 and HgCl2. The amino acid sequence of the enzyme showed 46% identity to urocanase from Pseudomonas putida , but thiourocanate hydratase had no urocanase activity. [ABSTRACT FROM AUTHOR]

Chronic kidney disease (CKD), characterized as renal dysfunction, is recognized as a major public health problem with high morbidity and mortality worldwide. Unfortunately, there are no obvious clinical symptoms in early stage disease until severe damage has occurred. Further complicating early diagnosis and treatment is the lack of sensitive and specific biomarkers. As such, novel biomarkers are urgently needed. Metabolomics has shown an increasing potential for identifying underlying disease mechanisms, facilitating clinical diagnosis and developing pharmaceutical treatments for CKD. Recent advances in metabolomics revealed that CKD was closely associated with the dysregulation of numerous metabolites, such as amino acids, lipids, nucleotides and glycoses, that might be exploited as potential biomarkers. In this review, we summarize recent metabolomic applications based on animal model studies and in patients with CKD and highlight several biomarkers that may play important roles in diagnosis, intervention and development of new therapeutic strategies. • Chronic kidney disease is a major public problem with high morbidity and mortality. • Potential biomarkers are useful for the diagnosis of chronic kidney disease. • Metabolomics shows the potential for biomarker discovery and clinical diagnosis. • Biomarkers provide new therapeutic strategy for patient with chronic kidney disease. [ABSTRACT FROM AUTHOR]

Immunoglobulin G (IgG) glycans are emerging as a new putative biomarker for biological age and different diseases, requiring a robust workflow for IgG glycome analysis, ideally beginning with a simple and undemanding sampling procedure. Here, we report the first comprehensive study on total N-glycans of IgG isolated from dried blood spots (DBSs), which was performed in a high-throughput mode. We compared the IgG N-glycan profiles originating from DBS with those originating from plasma, compared different media for DBS collection, evaluated analytical variation and assessed IgG N-glycan profile stability for different storage conditions. In conclusion, we show that DBSs are a good and stable source material for a robust IgG N-glycan analysis by ultra-performance liquid chromatography, suitable for blood sampling in conditions where no trained personnel and necessary laboratory equipment are available. [ABSTRACT FROM AUTHOR]

Etoxazole is a newly registered and widely used acaricide. However, its metabolites were not fully understood and might exhibit similar or even higher toxicity than parent compound. Therefore, in this study, the metabolites of etoxazole in citrus, soil and earthworms were firstly identified by an ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-QTOF/MS). Four potential metabolites in citrus, 11 in soil, and 8 in earthworms were determined. These metabolites were then further structural elucidated based on the fragment pathways, and accurate mass measurement. The distributions of etoxazole and its main metabolites (M1, M2, M3, M4 and M5) which were identified as the dehydrogenation, hydrolysis, oxidation products of etoxazole (M0) were also monitored in citrus, soil and earthworms at different exposure periods. The 45 days exposure experiment showed that M0 gradually decreased in citrus and soil samples by 80% and 28% of the initial amounts, respectively. In earthworm samples, M0 accumulated in the bodies of the worms during 24 days exposure and then decreased with time. The dissipation rate of etoxazole were citrus > earthworms > soil. Concentrations of M1 and M3 in soil were found continuously increased with time during the experimental period. Moreover, the persistence of M1 in earthworm samples was also observed. Great attention should be paid to these two compounds due to their potential risks to both environmental and human health. • Eleven metabolites of etoxazole were detected in citrus, soil and earthworms. • Fragment pathways of etoxazole were evaluated in three matrices. • Dissipation behaviors of etoxazole and its major metabolites were monitored. • Dissipation rates of etoxazole were citrus > earthworms > soil. [ABSTRACT FROM AUTHOR]

Abstract Although long chained PFASs have been phased-out in several countries, their persistence in the environment and bioaccumulative potential cause the environmental and biotic concentrations to remain high, highlighting the need to further monitor these pollutants. Currently several methods are used for the quantification of perfluoroalkyl substances (PFASs) in biological matrices including different ways to correct for recovery losses, each with its specific pros and contras. With this paper we aim to re-evaluate current methodologies and to create an updated new analytical guideline that is applicable for both abiotic and biotic matrices. The developed LC/MS/MS method was validated and shown to be specific, selective, linear, robust and sensitive. Reliable results could still be obtained 6 days after extraction. The recoveries varied, depending on the matrix, between 1% and 100%, but nevertheless, a high accuracy was obtained even at the lowest recoveries. A reduction of sample mass could significantly increase method recoveries and therefore it is highly recommended to take less matrix. We confirmed that using the ISTD closest in terms of functional group and carbon chain length is a suitable method for the quantification of PFASs that lack a corresponding ISTD. The newly described method was, depending on the matrix, similar in terms of sensitivity and reliability compared to a frequently used method and could be used simultaneously in future monitoring studies. Therefore, we recommend to select the purification method based on the target analytes as well as the sample matrix. Capsule The newly described method was similar in terms of sensitivity and reliability compared to a frequently used method and a selection of purification methods should be based on the target analyte and sample matrix. Highlights • Most extraction procedures focus on only a group of analytes or matrices. • We developed and validated a new extraction method based on weak anion exchange. • 15 target analytes and 9 environmental and biotic matrices were selected. • The use of internal standards was recommended over an external calibration curve. • A selection of an extraction method should be based on the matrix and target analyte. [ABSTRACT FROM AUTHOR]

A fast ultra-performance liquid chromatography method was developed for the separation and quantification of doxycycline, 4-epidoxycycline, and 6-epidoxycycline in the muscles of channel catfish, shrimp, eel and turtle. The analytes were separated by comprehensive optimization of the chromatographic conditions. The extraction method was performed using a modified QuEChERS methodology. 2 g of muscle sample were mixed with 5 mL Mcllvaine buffer (pH 4), and 4 g of sodium sulfate and 2 g of sodium chloride were added for liquid-liquid partitioning. The mixture was agitated for 30 s and extracted with 10 mL of acidified acetonitrile. The resulting extract was purified using 200 mg of a C18-silica adsorbent. The samples were analyzed using ultra-performance liquid chromatography with ultraviolet detection using a BEH C18 column (2.1 mm ×100 mm, 1.7 μm). The limits of detection were less than 25 μg/kg and the limits of quantitation were less than 50 μg/kg for all analytes. The recoveries of the analytes were from 62.3% to 89.0% with relative standard derivations below 10.0%. The method provided efficient extraction and purification that enabled rugged and low-cost determination of the analytes. [ABSTRACT FROM AUTHOR]

Highlights • Twelve main phenolic compounds (PC) were identified in different rice varieties. • Bran and husk provide more than 90% of PC and antioxidant activity of whole rice. • Ferulic acid, gallic acid and protocatechuic acid were the highest 3 PCs in rice bran. • P-Hydroxybenzaldehyde was the main PC existed in rice husk (14.46–23.72 μg·g−1). • Japonica rice has significant higher PC and antioxidant activity than Indica rice. Abstract Utilization of phenolic compounds in rice husk and bran is important for improving the functionality of rice by-products. Eight rice varieties planted in different area were selected to analyze the phenolic compounds distribution of fractions in Japonica and Indica rice by using UPLC-MS method. A total of 12 phenolic compounds were identified in all rice varieties. Ferulic acid, gallic acid, protocatechuic acid and syringic acid were the dominant phenolic compounds in rice bran, while p-Hydroxybenzaldehyde was the main phenolic compounds existed in rice husk (14.46–23.72 µg·g−1). Bran and husk fractions provide more than 90% of phenolic compounds and antioxidant activity of whole rice. Regardless of the planting environmental effects, Japonica rice has significant higher phenolic compounds and antioxidant activity than Indica rice (P < 0.05). Therefore, it can be concluded that the distribution of phenolic compounds were strongly correlated with the rice varieties and fractions. [ABSTRACT FROM AUTHOR]

Abstract Aberrant protein glycosylation may reflect changes in cell metabolism of type II diabetes mellitus (T2DM) and offers fresh vistas for discovering potential biomarkers. However, the functional significance of T2DM N-glycan alterations is underexplored, since to date, N-glycan profiling studies have been performed in selected populations. Geographically and genetically isolated populations are needed for validation of specific biomarkers. This age-sex matched cross sectional study comprising 232 T2DM patients and 219 controls was conducted in Ghana, Western Africa. Blood plasma samples were collected for clinical assessment after which plasma N-glycans were freed and analysed by ultra-performance liquid chromatography (UPLC). High branching (HB) [W = 46328; q = 0.00072], tri-galactosylated (G3) [W = 44076; q = 0.00096], antennary fucosylated (FUC_A) [W = 43055; q = 0.0000763], and triantennary (TRIA) [W = 44624; q = 0.0025], N-glycan structures were increased in T2DM whereas low branching (LB) [W = 46328; q = 0.00072], non-sialylated (S0) [W = 46929; q = 0.00292], monogalactosylation (G1) [W = 44091; q = 0.0000763], core fucosylation (FUC_C), [W = 46497; q = 0.00096], biantennary galactosylation (A2G) [W = 45663; q = 0.000763], and biantennary (BA) [W = 46376; q = 0.00072], structures were decreased compared to controls. Nine N-glycan peaks (GPs (GP1, GP4, GP7, GP11, GP17, GP19, GP22, GP26, GP29)) were found to predict case status based on Akaike's information criterion (AIC) and Bayesian information criterion (BIC) model selection. Adjusting for age, sex and other co-variates in this model yielded an area under the curve (AUC) of 80.5% with sensitivity of 79% and specificity of 73%, indicating the predicting power of N-glycans as robust biomarkers. Our results show that hyperglycemia influences N-glycan complexities among Ghanaians. N-glycan profiling in distinct populations has affirmed the potentiality of N-glycan profiles as generic biomarkers which may facilitate better prognosis for T2DM. Highlights • T2DM was associated with a decreased core fucosylated plasma N-glycans. • T2DM was associated with decreased low-branching plasma N-glycans. • T2DM was associated with increased high branching plasma N-glycans. • T2DM was associated with increased disialylated and trisialylated plasma N-glycans. • The area under the curve was 80.5% indicating the good predicting power of N-glycans. [ABSTRACT FROM AUTHOR]

A green, efficient and easy sample pretreatment method of magnetic ionic liquid-based liquid-liquid microextraction (MIL-based LLME) combined with a sensitive, rapid and precise analytical method of ultra-performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry (UPLC-QqQ/MS2) was developed to simultaneously - determining of neurotransmitters (NTs) in biosamples. Two magnetic ionic liquids (MILs), [P 6,6,6,14 ] 3 [GdCl 6 ] and [P 6,6,6,14 ] 2 [CoCl 4 ] tested, and the latter was selected as the extraction solvent due to its advantages of visual recognition, paramagnetic behavior and higher extraction efficiency. Facile magnetic separation of MIL containing analytes from matrix was realized by applying external magnetic field without rather than centrifugation. Experimental parameters that would influence the extraction efficiency, including type and amount of MIL, extraction time, speed of the vortex process, salt concentration, and environmental pH, were optimized obtained. The proposed method was successfully applied to the simultaneous extraction and determination of 20 NTs in human cerebrospinal fluid and plasma samples. Excellent analytical performance indicates the broad potential of this method for clinical diagnosis and therapy of neurological diseases. [Display omitted] • Facile extraction of neurotransmitters using magnetic ionic liquid. • Simultaneous determination of 20 neurotransmitters by tandem mass spectrometry. • Human cerebrospinal fluid and plasma sample were tested. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: Some trace amounts of urea herbicide residues can be transferred to humans via the food chain, thereby being potentially harmful to human health. The development of a robust analytical methodology for effective sample preparation and simultaneous determination of herbicide residues in vegetable samples is required for achieving food safety. RESULTS: The diuron–molecularly imprinted polymers (MIPs) synthesized have excellent affinity and high selectivity to phenylureas (monolinuron, isoproturon, diuron and linuron) and tebuthiuron. A novel automated procedure with better selectivity for vegetable sample treatment was developed by integrated matrix solid‐phase dispersion–accelerated solvent extraction clean‐up in situ. Five herbicides can be baseline separated with runtime down to 5 min by ultra‐performance liquid chromatography, and good linearity was obtained with a correlation coefficient (r) of 0.9999. The limit of quantification of the method was in the range of 0.8–2.3 µg kg−1. Diuron residue in cherry tomato sample was found to be 40 µg kg−1. CONCLUSION: The developed method has satisfactory selectivity, good linearity, high sensitivity and accuracy as well as speediness, and can ensure rapid selective extraction and sensitive multi‐residue analysis at low microgram per kilogram levels of the herbicides in vegetable food. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Isotope dilution solid phase extraction UPLC-MS/MS has been used to develop a robust and rapid methodology for the determination of eight specific metabolites of organophosphate and pyrethroid pesticides in human urine. The use of methanol:acetone (25:75 v /v) affords an improvement in extraction efficiency in comparison to these individual solvents. The use of synthetic urine improves selectivity and limits of detection for the calibration straight lines. The method provides detection limits of 14–69 pg/ml and 18–19 pg/ml for the organophosphate and pyrethroid metabolites, respectively. Urine analyses of these metabolites in urban non-occupationally exposed individuals and farm workers shows that ingestion of these pesticides occurred in both populations. The concentrations of organophosphate pesticide metabolites in the latter were twofold than those from non-exposed populations. [ABSTRACT FROM AUTHOR]

Drought tolerant rhizobacteria of the genus Bacillus, Enterobacter, Moraxella and Pseudomonas colonizing the root system of Acacia arabica were isolated to mitigate the drought stress of wheat (Triticum aestivum L.). In vitro auxin production by rhizobacteria was quantified by Ultra High Performance Liquid Chromatography (UPLC). Analysis of the crude extracts detected the indole-3-acetic acid (IAA), indole-3-carboxylic acid (ICA) and indole-3-lactic acid (ILA). Highest IAA production of 25.9 µg ml−1 was observed for Bacillus amyloliquefaciens S-134. Pot trials were conducted to evaluate the role of rhizobacteria to enhance the growth of wheat at different water regimes. At highest water stress i.e. 10% field capacity (FC), significant improvement of shoot length was observed with B. amyloliquefaciens S-134. For yield parameters, B. muralis D-5 and E. aerogenes S-10 recorded 34% and 1 fold increases for spike length and seed weight, over respective control at 10% FC. Mixed culture combinations of M-2 (B. thuringiensis S-26, D-2, B. amyloliquefaciens S-134, B. simplex D-11) and M-3 (M. pluranimalium S-29, B. simplex D-1, B. muralis D-5, P. stutzeri S-80) showed significant improvement for tillers and number of spikelets. In conclusion, application of the drought tolerant rhizobacteria can help to overcome productivity losses in drought prone areas. [ABSTRACT FROM AUTHOR]

The purpose of this study was to validate a rapid, simple and accurate method using ultra-performance liquid chromatography (UPLC) for the simultaneous determination of 26 anti-diabetic compounds in illegally adulterated dietary supplements. The method was validated for specificity, linearity, limit of detection, limit of quantitation, precision, accuracy, recovery and stability. All compounds were separated with a resolution of over 1.5. The limits of detection and quantitation were 0.10-1.70 and 0.30-5.10 µg g-1 in a solid sample, respectively; the corresponding values were 0.10-1.25 and 0.30-3.75 µg ml-1 in a liquid sample. The correlation coefficient was > 0.99, precisions were 0.11-3.30% (intra-day) and 0.05-6.15% (inter-day), and accuracies were 83-108% (intra-day) and 85-109% (inter-day). The recoveries were measured with six dosage forms, and the results were acceptable as 87-117% with relative standard deviations ≤ 6.44%. The relative standard deviations of stability were ≤ 3.40% and the standard solution was stable for 48 h. Ninety-six samples were obtained from on/off-line markets and were analysed using the developed method. Among these samples, pioglitazone and glibenclamide were found in seven samples and the concentrations of each compound were 0.15% and 0.26-0.51%, respectively. With the increasing adulteration of dietary supplements with anti-diabetic drugs, this method may be helpful to protect public health and safety. [ABSTRACT FROM AUTHOR]

1. Osthole, a coumarin compound from plants, is a promising agent for the treatment of metabolic diseases, including hyperglycemia, fatty liver, and cancers. Studies indicate that the peroxisome proliferator-activated receptors (PPAR) α and γ are involved in the pharmacological effects of osthole. Thein vitroandin vivometabolism of osthole and its biological activity are not completely understood. 2. In this study, ultra-performance chromatography electrospray ionization quadrupole time-of-flight mass spectrometry (UPLC–ESI–QTOFMS)-based metabolomics was used to determine the metabolic pathway of osthole and its influence on the levels of endogenous metabolites. Forty-one osthole metabolites, including 23 novel metabolites, were identified and structurally elucidated from its metabolismin vitroandin vivo. Recombinant cytochrome P450s (CYPs) screening showed that CYP3A4 and CYP3A5 were the primary enzymes contributing to osthole metabolism. 3. More importantly, osthole was able to decrease the levels of lysophosphatidylethanolamine (LPE) and lysophosphatidylcholine (LPC) in the plasma, which explains in part its modulatory effects on metabolic diseases. 4. This study gives the insights about the metabolic pathways of ostholein vivo, including hydroxylation, glucuronidation, and sulfation. Furthermore, the levels of the lipids regulated by osthole indicated its potential effects on adipogenesis. These data contribute to the understanding of the disposition and pharmacological activity of ostholein vivo. [ABSTRACT FROM AUTHOR]

Two different in vitro static gastrointestinal digestion (GID) protocols were applied to investigate the profile of casein phosphopeptides (CPPs) released from protected designation of origin (PDO) Trentingrana cheese. CPPs in the gastrointestinal digestates were selectively precipitated and identified by ultra-performance liquid chromatography coupled to high-resolution mass spectrometry. Digestion parameters adopted during gastric and intestinal phases of the two GID procedures were pivotal in the resulting CPP patterns. A standardized digestive protocol mimicking in vivo conditions, made available half of the CPPs identified following a simpler procedure based only on the action of pepsin and pancreatin. Independently of the GID protocol used, the mono-phosphorylated CPPs were the most abundant (>55%) followed by bi- (23–29%) and tri-phosphorylated (8–18%) peptides. Alfas1-casein was the parent fraction mainly contributing to CPP release. The number of peptides containing the biofunctional cluster sequence SerP–SerP–SerP–Glu–Glu almost overlapped in the digestates from the two GID models. About a half of these peptides was common between the two GID models, and a large part of them derived from αs2- and β-caseins. Overall, results of this investigation proved that CPP profiles of in vitro digestates of Trentingrana were similar to those previously reported for Grana Padano PDO using the same digestion protocols. [ABSTRACT FROM AUTHOR]

In this study, we developed a UPLC-PDA and LC-Q-TOF/MS method to identify and measure the following prohibited substances that may be found in dietary supplements:triaminodil, minoxidil, bimatoprost, alimemazine, diphenylcyclopropenone, α-tradiol, finasteride, methyltestosterone, spironolatone, flutamide, cyproterone, dutasteride, and testosterone 17-propionate.The method was validated according to International Conference on Harmonization guidelines in terms of specificity, linearity, accuracy, precision, LOD, LOQ, recovery, and stability. The method was completely validated showing satisfactory data for all method validation parameters. The linearity was good (R2 > 0.999) with intra- and inter-day precision values of 0.2–3.4% and 0.3–2.9%, respectively. Moreover, the intra- and inter-day accuracies were 87–102% and 86–103%, respectively, and the precision was better than 9.4% (relative standard deviation).Hence, the proposed method is precise and has high quality,and can be utilised to comprehensively and continually monitor illegal drug adulteration in various forms of dietary supplements. Furthermore, to evaluate the applicability of the proposed method, we analysed 13 hair-growth compounds in 78 samples including food and dietary supplements. Minoxidil and triaminodil were detected in capsules at concentrations of 4.69 mg/g and 6.54 mg/g. In addition, finasteride was detected in a tablet at 13.45 mg/g. In addition, the major characteristic fragment ions were confirmed once again using LC-Q-TOF/MS for higher accuracy. [ABSTRACT FROM AUTHOR]

Direct oral anticoagulants (DOACs) are among the most effective options to prevent serious thromboembolic events in patients with atrial fibrillation. Coagulation assays are used to assess DOAC activity, but lack the possibility to quantify drugs with concurrent pharmacodynamic effect. We developed a selective multi-drug assay to analyze apixaban, betrixaban, dabigatran, edoxaban, edoxaban M4, and rivaroxaban with ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC/MS/MS) in plasma fulfilling all requirements of the FDA und EMA guidelines for bioanalytical method validation. Plasma samples were extracted using solid phase extraction in a 96-well micro volume format. Chromatographic separation was performed on a Waters BEH Phenyl 1.7 μm column coupled to tandem mass spectrometry. Extraction recoveries exceeded 80 %. Concentrations of 1–1000 ng/ml can be precisely quantified (correlation coefficient of >0.99) using 100 μL plasma volume. Intra-day and inter-day accuracies ranged between 91.0 % and 116 %. Precisions at low and high concentrations were below 13.3 %. The method was applied within a clinical drug trial and eight short pharmacokinetic profiles of patients under DOAC therapy were analyzed. The assay allows for highly sensitive and selective simultaneous quantification of DOACs in patient plasma samples. [ABSTRACT FROM AUTHOR]

The quality control of Polygala tenuifolia Wild. is a major challenge in its clinical application. In this paper, a new strategy for the quality evaluation of P. tenuifolia extracts was verified through reverse-phase ultra-performance liquid chromatography (UPLC). The quantitative analysis of multi-components by a single marker (QAMS) was conducted with 3,60-disinapoyl sucrose as an internal reference substance. Eight components (i.e., sibiricose A5, sibiricose A6, glomeratose A, tenuifoliside A, tenuifoliside B, tenuifoliside C, sibiricaxanthone B, and polygalaxanthone III) were determined based on the relative correction factors. The concentrations of these components were also determined by applying a conventional external standard method. The cosine value confirmed the consistency of the two methods (cosine ratio value >0.999920). Hierarchical cluster analysis, radar plots, and discriminant analysis were performed to classify 23 batches of P. tenuifolia extracts from Shanxi, Hebei, and Shaanxi in China. Results revealed that QAMS combined with radar plots and multivariate data analysis could accuratelymeasure and clearly distinguish the different quality samples of P. tenuifolia. Hence, QAMS is a feasible and promising method for the quality control of P. tenuifolia. [ABSTRACT FROM AUTHOR]

Ferula sumbul (Umbelliferae) roots have a characteristic musk odour and it has been traditionally used for relieving anxiety, as a sedative in hysteria and other nervous disorders. Present investigation aims to develop and validate a simple, robust, accurate and fast analytical ultra-performance liquid chromatography technique for the estimation of valerenic acid in F. sumbul roots. F. sumbul root extract was prepared by refluxing the powdered roots with methanol for 30 minutes. A simple method for the estimation of valerenic acid has been developed and validated using ultra-performance liquid chromatography with photodiode array detector. The estimation was achieved using BEH Shield RP, C-18 column (2.1×50 mm, 1.7 μm) with isocratic elution of methanol and 0.5% phosphoric acid (75:25) at a flow rate of 0.25 ml/min and detection at 218 nm. The method has been developed for the first time and is accurate with good linearity (r2>0.998). F. sumbul roots were found to contain 12.62±0.074 μg/g valerenic acid. The developed method can be selectively used for the estimation of valerenic acid in the roots of F. sumbul. All the validation parameters were found to be within the permissible limits prescribed by ICH guidelines. [ABSTRACT FROM AUTHOR]

There has been a number of reports of natural products contaminated with illegal adulterants that threaten consumer health because of their adverse pharmacological effects worldwide. In this study, a multi-residual ultra-performance liquid chromatography method with quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) was applied for the identification of sildenafil added into a herbal honey mixture used as an immune system booster. Electrospray ionization (ESI) source was applied and operated in the positive ion mode. The mobile phase consisted of 0.1% formic acid aqueous solution/acetonitrile (70:30, v/v) using the isocratic gradient elution system at a detection wavelength of 290 nm. The compound of sildenafil added into traditional herbal mixed honey was identified according to the spectrum, chromatographic behavior, and mass spectral data were identified by comparison with the reference substance. The method is selective, sensitive and can be used to detect the sildenafil illegally added into traditional herbal medicinal preparations. [ABSTRACT FROM AUTHOR]