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Microplastics (MPs) in the air are one of the major concerns due to their possible health risks. In addition, airborne microplastics act as a carrier for several toxic air pollutants and cause carcinogenic, mutagenic and teratogenic effects. Nylon 66 is one of the most abundant MPs in the microenvironments. In this study, we report an optimized method for the quantification of nylon 66 MPs present in the fine particulate matter (PM2.5) using high-performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS). The optimized method exhibited excellent linearity, recovery rates, intraday and interday precision and sensitivity. The optimized method was deployed to carry out a pilot study to measure the mass concentrations of nylon 66 microplastics present in the inhalable fraction of particulate matter collected in a shopping complex. The observed mass concentrations of nylon 66 MPs in this study are in the range from 0.30 ng m−3 to 4.37 ng m−3. This study demonstrates the presence of inhalable fraction of nylon 66 MPs in the indoor environment and their mass concentrations were determined using HPLC-MS/MS. [ABSTRACT FROM AUTHOR]

A method for determining human epidermal growth factor (hEGF) in cosmetics was developed using solid-phase extraction with high-performance liquid chromatography – tandem mass spectrometry. The sample was extracted and purified by a mixed anionic solid-phase extraction column (MAX), and the eluent was passed through a nylon filter membrane into a polypropylene vial. The matrix-matched external standard method was used to quantify the analyte in multi-reaction monitoring mode. The analyte had an excellent peak shape within 11 min with a linear range from 5 to 80 ng/mL and a linear correlation coefficient (r) of 0.9995. The limit of detection and limit of quantification were 0.75 and 2.5 μg/kg, respectively. The recovery of the target was from 81.5% to 88.8%, and the relative standard deviation was between 1.16% and 5.07%. The results met the International Organization for Standardization 12787 standard. The established method was successfully applied to 30 cosmetic samples. The proposed method is sensitive, accurate, reliable, and suitable for the quantitative confirmation of hEGF and monitoring its illegal addition to cosmetics. [ABSTRACT FROM AUTHOR]

Accurate measurement of endogenous steroid hormones in serum is a powerful tool for understanding the status of human adrenal diseases. Isotope dilution–liquid chromatography–tandem mass spectrometry is the most commonly used method for determination of steroids in serum. In this study, we used a laboratory-constructed quadrupole-linear ion trap (Q-LIT) tandem mass spectrometer to develop a new method for the quantification of five steroid hormones in serum. A simple and efficient pretreatment was improved, wherein the serum was extracted once by a mixed solvent of 1.0 mL of ethyl acetate and n-hexane. Using the optimized method, the regression coefficients of the calibration curves were all higher than 0.99, the limits of detection were from 0.31 to 1.25 ng mL−1, and the limits of quantification were between 1.00 and 2.50 ng mL−1. The intra-day (n = 3) relative standard deviations ranged from 4.24% to 13.79%, and the inter-day (n = 3) relative standard deviations from 3.99% to 11.43%. After internal standard correction, the relative recoveries of all steroids were from 86.08% to 106.60%. Twenty-two serum samples were analyzed by Q-LIT, which was compared with commercial triple quadrupole mass spectrometer. The results of the instruments had high consistency. Therefore, Q-LIT accurately quantified steroid hormones in human samples and may be used for clinical diagnosis and monitoring of hormone-dependent diseases. [ABSTRACT FROM AUTHOR]

A simple, rapid and sensitive method for the determination of aflatoxins in peanut oil was developed using MIL-101(Cr) material filled syringe filter for one-step solid-phase extraction (SPE) with high-performance liquid chromatography—tandem mass spectrometry (HPLC-MS/MS) detection. The MIL-101(Cr) sorbent was characterized and its mass, the loading solution, and the eluent were optimized; under these conditions, a matrix matching internal standard method was developed. The linear range was from 0.1 to 20 ng/mL with correlation coefficient (r) exceeding 0.9998. The recoveries were between 94.7% and 105.9% with relative standard deviations from 2.02% 6.88%. The recoveries of inter-day and intra-day measurements were from 93.0% to 98.5% and 97.6% to 100.7%. The precision values for inter-day and intra-day analyses were from 6.09% to 7.68% and 2.56% to 4.30%, respectively. The pretreatment efficiency of the developed method was superior to literature procedures and used to determine aflatoxins in 126 peanut oil samples from local markets. 38 samples had positive results and 1 sample exceeded the allowable limit. Hence, the developed protocol was suitable for the determination of aflatoxins in peanut oil. [ABSTRACT FROM AUTHOR]

A rapid and simple magnetic solid phase extraction-liquid chromatography-tandem mass spectrometry method is reported to determine vancomycin in human plasma. The Fe3O4@SiO2 nanocomposite was prepared using silica nanoparticles obtained from rice husk waste and its modification using ammonia solution to obtain a Fe3O4@SiO2-NH2 nanohybrid as a new sorbent. The structure and morphology of the sorbent were characterized by X-ray diffraction, field emission scanning electron microscopy, and Fourier transform infrared spectroscopy. The nanosorbent was successfully used in magnetic solid phase extraction without hazardous solvents in 9 min with analysis by high-performance liquid chromatography – tandem mass spectrometry. Under the optimized conditions, the method provided a linear range from 10 to 1000 ng mL−1. The intra-day (n = 3) and inter-day precision (n = 3 working days) were below 10% relative standard deviation. The developed procedure was employed for determining vancomycin in human plasma with recoveries from 84.0 to 109.5% for spiked samples. [ABSTRACT FROM AUTHOR]

Tea (Camellia sinensis L.) is a high valued beverage worldwide since ancient times; more than three billion cups of tea are consumed each day. Leaf extracts of the plant are used for food preservation, cosmetics, and medicinal purposes. Nevertheless, tea contaminated with mycotoxins poses a serious health threat to humans. Mycotoxin production by tea fungi is induced by a variety of factors, including poor processing methods and environmental factors such as high temperature and humidity. This review summarizes the studies published to date on mycotoxin prevalence, toxicity, the effects of climate change on mycotoxin production, and the methods used to detect and decontaminate tea mycotoxins. While many investigations in this domain have been carried out on the prevalence of aflatoxins and ochratoxins in black, green, pu-erh, and herbal teas, much less information is available on zearalenone, fumonisins, and Alternaria toxins. Mycotoxins in teas were detected using several methods; the most commonly used being the High-Performance Liquid Chromatography (HPLC) with fluorescence detection, followed by HPLC with tandem mass spectrometry, gas chromatography and enzyme-linked immunosorbent assay. Further, mycotoxins decontamination methods for teas included physical, chemical, and biological methods, with physical methods being most prevalent. Finally, research gaps and future directions have also been discussed. [ABSTRACT FROM AUTHOR]

A paper spray tandem mass spectrometric (PS-MS/MS) method without column separation was developed for the rapid screening of clonidine in dietary supplements. PS-MS/MS provided acceptable performance compared to high-performance liquid chromatography – tandem mass spectrometry (HPLC-MS/MS) in terms of limits of detection and quantification, accuracy, and precision. To overcome ionization suppression of complicated plant-based pharmaceutical products, nizatidine, tizanidine, and apraclonidine were investigated as internal standards. A more similar structured internal standard is most suitable for matrix effect compensation. The developed method has advantages of simplicity and speed for the screening of clonidine in dietary supplements. [ABSTRACT FROM AUTHOR]

A commercial formulation called prothioconazole·kresoxim-methyl 50% water dispersible granule (WG), used to control the powdery mildew, is under registration for use on cucumbers. Therefore it is urgent to validate the reliability of the recommended good agricultural practices (GAP) conditions (187.5 g a.i. ha−1, three sprays with a 7-d interval, and a pre-harvest interval of 3 d) by conducting field trials in 12 regions in China, as required by national regulations, with a subsequent risk assessment. The residues of prothioconazole-desthio and kresoxim-methyl in field samples were determined using QuEChERS coupled with high-performance liquid chromatography – tandem mass spectrometry (HPLC-MS/MS). On the suggested pre-harvest interval (PHI, 3 d), the residual concentrations of prothioconazole-desthio (no maximum residue limit set in China) and kresoxim-methyl (maximum residue limit = 0.5 mg/kg) in cucumbers were 0.01–0.020 and 0.01–0.050 mg/kg, respectively. The acute risk quotients of prothioconazole-desthio in cucumbers were no higher than 0.079% for Chinese consumers. The chronic dietary risk quotient of kresoxim-methyl and of prothioconazole-desthio for different groups of consumers in China ranged from 2.3% to 5.3% and from 1.6% to 4.6%, respectively. Thus, prothioconazole·kresoxim-methyl 50% WG sprayed on cucumbers under the recommended GAP information can pose a negligible risk for Chinese consumers. [ABSTRACT FROM AUTHOR]

Molnupiravir a novel oral broad-spectrum antiviral drug initially developed for the treatment of COVID-19, was quantified using UV spectrophotometric and high-performance liquid chromatographic methods. The linear regression analysis used to build the equations for the multivariate calibration method used the correlation between absorbance and concentration at a set of five different wavelengths. The suggested method can separate Molnupiravir and its breakdown products using a C18 column containing ethanol and phosphate buffer (42.5:57.5% v/v), a flow rate fixed at 0.9 mL/min, and detection done at 235 nm. The suggested techniques were examined and approved in accordance with ICH Q2 (R1) standards. For the UV and HPLC methods, the linearity ranges for molnupiravir were 4-9 and 10-150 g/ml, accuracy, repeatability, and selectivity, with R2 values were 0.9999 and 0.9999 with recoveries between 98 and 102% and 2% RSD. The unique strategy was additionally assessed utilising three ways, including additional assessment techniques, such as GAPI, AES, and AGREE, and it was discovered to be environmentally friendly. Based on our findings, developing new pharmaceutical drugs may benefit from using UV and HPLC procedures with Green Analytical Performances using the Quality by Design methodology to assess drug stability. [ABSTRACT FROM AUTHOR]

A method is reported for the simultaneous determination of ceftazidime and avibactam in human plasma and cerebrospinal fluid utilizing high-performance liquid chromatography – tandem mass spectrometry (HPLC-MS/MS). The validated method was used to monitor the drugs in the treatment of central nervous system infections. The analytes were extracted from plasma and cerebrospinal fluid by simple protein precipitation using acetonitrile. A reversed-phase HSS T3 column (5.0 μm, 4.6 × 100 mm, Waters) was employed for the separation with a total analysis time of 5 minutes. Ceftazidime and avibactam eluted in 2.15 min and 2.87 min, respectively. The acquisition was separated into two periods to allow analysis in different ionization modes. A multi-reaction monitoring analysis was performed with the transition m/z 547.2–468.1 for ceftazidime, and m/z 552.3–468.1 for ceftazidime-d5 (positive mode), m/z 263.9–96.1 for avibactam, and m/z 136.8–92.8 for salicylic acid (negative mode). The plasma calibration curves of the analytes displayed good linearity across the range from 1 to 100 μg/mL for ceftazidime and 0.1–20 μg/mL for avibactam. Calibration curves for cerebrospinal fluid assay were established from 0.4 to 16 μg/mL (ceftazidime) and 0.2–8 μg/mL (avibactam). The accuracy was between 89.5% and 108.5%. The within- and between-batch precisions with the relative standard deviation were lower than 15%. The developed method had no observed matrix effects. The analytes were stable during the analytical and sample processing. The developed and validated method was successfully applied in routine clinical practice and helps to assess the adequacy of therapy and ensure sufficient ceftazidime and avibactam levels in central nervous system infections. [ABSTRACT FROM AUTHOR]

Plastic recycling is necessary to reduce pollution. However, the impurities in recycled plastics restrict their applications. Potential contaminants in recycled plastics were investigated by untargeted and targeted liquid chromatography-mass spectrometry (LC-MS). More than 2000 features were screened by comparing the recycled plastics with food contact polyolefin materials. A total of 126 substances was identified using the mzCloud database. In order to assess the risk of recycled plastics, Cramer rules were applied to predict the safety levels of the identified compounds. 23 identified Cramer class III compounds were assigned, including plasticizers, antioxidants, and flame retardants. Six more commonly identified toxic compounds were further characterized by standards using tandem mass spectrometry. These results suggested that the identification of contaminants in recycled plastics by LC-MS and mzCloud match was reliable. Additionally, their concentrations were determined by LC-MS to estimate the potential risk of recycled plastics. The results show that the organic additives in recycled plastics and food contact polyolefins are significantly different. Recycled plastics may present a safety risk and should be assessed before use in some applications. [ABSTRACT FROM AUTHOR]

Liquid chromatography – tandem mass spectrometry (LC-MS/MS) is routinely applied for the determination of toxins associated with diarrhetic shellfish poisoning (DSP) as a part of the Japanese official method. For scallops, not only the edible part but also the midgut gland may be used for analysis. In this study, the matrix effects in the LC-MS/MS-based determination of okadaic acid (OA) and dinophysistoxin-1 (DTX1) in the scallop midgut gland were evaluated to assess the impact on the accuracy of the results. The analyzed sample in an interlaboratory comparison study was subjected to the Japanese official method. The solutions obtained with and without a cleanup process (combination of hexane washing and solid-phase extraction using a C18 cartridge) were diluted to varying ratios and used for evaluation. For all prepared solutions, the ionization of OA and DTX1 was enhanced compared to the samples in methanol; the cleanup process did not sufficiently reduce the matrix effects. Although the dilution of the sample solution reduced the matrix effect, the improvement was limited. Another pretreatment technique is necessary for the accurate determination of DSP-associated toxins in this matrix. [ABSTRACT FROM AUTHOR]

Simple, accurate, precise and stable indicating HPLC methods were developed and validated to determine both related substances and the assay content of Remogliflozin etabonate (RME). The separation was established under optimized chromatographic condition using Waters e2695 HPLC coupled to Ultraviolet detector (UV) at 228 nm with Inertsil ODS-3V C18 column (250 mm x 4.6 mm, 5 μm), injection volume 10 μl for related substances and 20 μl for assay content determination. The mobile phase consisted of 10 mM KH2PO4 buffer with ortho-phosphoric acid pH 2.5. Gradient elution was maintained at a flow rate of 1.0 ml/min using 45°C column oven temperature for determination of the related substances and isocratic elution was maintained at a flow rate of 1.2 ml/min for assay content. The retention time for RME-01, RME-02, RME-03 and RME-04, RME-05 and RME were about 41.74 min, 11.42 min, 20.38 min, 37.16 min, 49.93 min, 25.05 min respectively. The linearity was found to be in the concentration range of 0.312-2.341 μg/ mL for RME-01, 0.306-2.292 μg/ mL for RME-02, 0.306-2.297 μg/ ml for RME-03 and 0.294-2.203 μg/mL for RME-04. The RME was subjected to acid, base, oxidation, and thermal degradation stress conditions. The method was validated according to the ICH guidelines for specificity, precision, linearity, accuracy and robustness and the values were found to be within the limits. [ABSTRACT FROM AUTHOR]

Heterocyclic aromatic amines (HAAs) are carcinogenic and mutagenic compounds formed by the cooking of meat and combustion of biomass. There are relatively few data on HAAs in atmospheric particulate matter (PM). We developed an analytical method using high performance liquid chromatography – tandem mass spectrometry (tandem quadrupole, HPLC-MS/MS(QqQ)) to analyze PM samples for 12 HAAs. We applied this method to an urban air standard reference material and wildfire-impacted PM2.5 from the 2018 wildfire season in Northern California. The PM sample matrix adversely impacted the MS/MS response, with high levels of ion suppression for sample masses >4 mg and higher ion suppression in wildfire-impacted particulate matter compared with the standard reference material. Despite detection limits at the low ng level, no HAAs were detected in the standard reference material, but β-carboline norharman (0.34 ng/m3) was detected in one wildfire sample. [ABSTRACT FROM AUTHOR]

A fast, straightforward, efficient, and high throughput reverse-phase high-performance liquid chromatography and electrospray ionization mass spectrometry method has been developed to analyze tea extracts containing polyphenols. The polyphenols detected in green tea (GT), black tea (BT), and paradise tropical tea (PTT) were separated in 18 min at wavelengths 254 nm, 260 nm, and 280 nm with a gradient elution on the RP-HPLC system. Our approach detected, identified, and quantified three catechins in the tea extracts analyzed, and the response at 280 nm wavelength was the best. The ESI-MS data confirmed the fragmentation patterns of the catechins detected in the tea extract. The validation data showed that the limit of detection (LOD) and limit of quantitation (LOQ) of catechins ranged from 5.26 ± 0.02 to 36.44 ± 0.02 ppb, and 17.52 ± 0.03 to 121.45 ± 0.16 ppb, respectively, for six catechins studied. The standard addition calibration approach used to quantify the catechin content in the tea extract simultaneously showed that PTT has a higher catechin content than GT and BT. The content of polyphenols in GT, BT, and PTT are summarized. This approach holds great promise for quality control studies to quantify polyphenols in nutritional products. [ABSTRACT FROM AUTHOR]

Macleaya cordata extracts (MCE) are listed as feed additives in animal production by the European Food Authority. The core components of MCE are mainly sanguinarine (SA) and chelerythrine (CHE). This study aims to investigate sex differences in the pharmacokinetics and tissue residues of MCE in rats. Male and female rates were intragastrically administered MCE (1.25 mg·kg−1 body weight and 12.5 mg·kg−1 body weight dose for 28 days). SA and CHE concentrations were determined using high-performance liquid chromatography/tandem mass spectrometry. The peak plasma concentration (Cmax) and area under the curve (AUC) of both CHE and SA were higher in female than in male rats (12.5 mg·kg−1 body weight group), whereas their half-life (T1/2) and apparent volume of distribution (Vd) was lower (p < 0.05). Tissue rfesidue analysis indicated that SA and CHE were more distributed in male than in female rats and were highly distributed in the caecum and liver. SA and CHE were completely eliminated from the liver, kidney, lung, heart, spleen, leg muscle, and caecum after 120 h, indicating they did not accumulate in rats for a long time. Overall, we found that the pharmacokinetics and tissue residues of SA and CHE of male and female rats showed sex differences. [ABSTRACT FROM AUTHOR]

Parabens are widely used as antimicrobial preservatives in cosmetic products and pharmaceuticals. Therefore, their presence in the environment is considered to be serious and their determination is important. This paper reports the development and validation of a new method based on solid-phase microextraction (SPME) and high-performance liquid chromatography – tandem mass spectrometry (HPLC-MS/MS) for the simultaneous determination of five parabens (methylparaben (MP), ethylparaben (EP), propylparaben (PP), butylparaben (BP) and benzylparaben (BzP)) in surface water. The polymer sorbent was obtained by the electropolymerization of 3,4-ethylenedioxythiophene on a stainless steel spring support. The parameters affecting the extraction efficiency of parabens were optimized. Under optimal conditions, the extraction recoveries ranged from 88 to 98% except for BzP (70%). Good linear responses were obtained with correlation coefficients (r2) exceeding 0.999. The detection limits were from 0.004 to 0.28 µg L−1. The method was successfully applied for the determination of parabens in lake water. [ABSTRACT FROM AUTHOR]

This study was to compare the pharmacokinetic characteristics of domestic altrenogest oral solution (DAOS) or imported altrenogest oral solution (IAOS) in healthy sows. A single administration (1 mg/kg body weight) of DAOS or IAOS was performed in sixteen healthy sows according to a two-period crossover design. Plasma concentrations of altrenogest (AT) were measured by high performance liquid chromatography coupled to a tandem mass spectrometer (HPLC-MS/MS) and the concentration-time data of AT was analyzed by WINNONLIN 5.2. It was suggested that the main pharmacokinetic parameters of DAOS and IAOS were as follows: Cmax was 227.59 ± 83.35 ng/mL and 152.83 ± 80.34 ng/mL, Tmax was 1.16 ± 0.52 h and 1.58 ± 0.85 h, t1/2 was 3.63 ± 0.72 h and 3.45 ± 0.63 h, MRT was 5.02 ± 0.79 h and 5.21 ± 0.87 h, AUC0–t was 1050.23 ± 409.80 h·ng/mL and 778.22 ± 397.84 h·ng/mL, and AUC0–∞ was 1060 h·ng/mL and 786 h·ng/mL, respectively. The relative bioavailability of DAOS was 134.9%. Above results indicated that oral DAOS was better absorbed than IAOS, Cmax of DAOS was higher than that of IAOS (p < 0.05). However, there was no significant difference in the main pharmacokinetic parameters between oral DAOS and IAOS (p > 0.05). Our data confirmed that the absorption, fast elimination and bioavailability of DAOS in sows were better than those of IAOS. [ABSTRACT FROM AUTHOR]

This study for the first time illustrates a comprehensive picture of the phenolic composition of Embelia adnata and Embelia gardneriana by high-performance liquid chromatography coupled with mass spectrometry analysis with ESI in negative ionisation. The analysis was performed in the methanolic extracts of different parts of these two species separately and identifies 54 individual phenolic compounds present in them. Among this by individual 36 and 28 compounds were recorded from E. adnata and E. gardneriana, respectively, and in this, 10 compounds were common in both the two species. The detected compounds come under the classes flavonoids, flavonoid glycosides, isoflavonoids, benzenoids, coumarins, stilbens, chalcones, polyphenols, gallic acid derivatives, tannins and different derivatives of various organic acids. [ABSTRACT FROM AUTHOR]

Urea is authorised in the European Union (EU) as feed additive for ruminants. Because of its high molecular nitrogen content, it is a substance for potential protein adulteration in non-ruminant feed. The EU defines a spectro-colorimetric method as an official control method for the determination of urea in feed, whereas the Association of Official Analytical Chemists (AOAC) in the United States recommends an enzymatic method. Discrepancies between results obtained by these different approaches have been reported, especially at low concentrations. Therefore, we developed and validated two methods for urea determination in compound feed, including pet food, and yeast (Saccharomyces cerevisiae) over a wide concentration range using high-performance liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) and fluorescence detection (HPLC-FLD) and compared performance with a commercial enzyme kit. Limit of detection (LOD) and limit of quantification (LOQ) were found to be 3 and 8 mg kg−1 for LC-MS/MS and 2 and 7 mg kg−1 for HPLC-FLD, respectively. For both methods, the variation coefficients ranged between 1.4% and 7.2% in ruminant feed used as reference material as well as spiked samples of complete feed for chicken, pet food for dogs and cats, as well as yeast. Recovery rates for spiked samples ranged from 86% to 105%. For real samples of complete feed for poultry, wet and dry pet food for cats and dogs and yeast amounts of urea between < LOD and 200 mg kg−1 relative to a feedingstuff with a moisture content of 12% were found. In comparison with the enzyme kit, the newly developed methods proved to be less time-consuming in sample preparation and more stable regarding matrix effects. [ABSTRACT FROM AUTHOR]

A rapid, simple, precise and accurate high performance liquid chromatographic (HPLC) analytical method was developed and validated for the determination of the active substances (a.s.) azoxystrobin, topramezone, acetamiprid, fluometuron and folpet in their respective commercially available formulations. The method was used for the analysis of samples under the frame of the national quality control program of plant protection products in the Greek market. Chromatographic separation of the active substances from additives and co-formulants is achieved using isocratic elution with acetonitrile and 0.1% phosphoric acid solution (60:40 v/v) at a flow rate of 0.4 mL min−1 on a C18 monolithic column (Chromolith Performance-RP18e 100 × 4.6 mm) and UV detection at 230 nm. Validation parameters of the method fulfilled acceptability criteria. Recovery of all individual compounds was in the range 97.8–100.9%. Precision expressed as relative standard deviation was lower than the theoretical values of the modified Horwitz equation. Correlation coefficients of linearity of response were better than 0.999. The benefits of the proposed method are significant reduction in analysis time and total cost since all analytes were determined with the same extraction procedures and chromatographic system. Analysis of real samples for all active ingredients confirmed fitness for purpose of the suggested method. [ABSTRACT FROM AUTHOR]

There is a strong need for a reliable marker of harmful alcohol consumption to identify injured patients that can benefit from alcohol interventions, and blood phosphatidyl ethanol (PEth) has not previously been tested on this population. This study aims to compare the performance of blood PEth concentration, blood alcohol concentration (BAC) and the Alcohol Use Disorders Identification Test Consumption (AUDIT-C) for the screening of alcohol misuse in trauma patients. Prospective cross-sectional study of 238 adult patients presenting in the emergency department with any type of trauma. PEth concentration was determined in whole blood by high-performance liquid chromatography with tandem mass spectrometry. Consent, AUDIT-C score and demographic data were obtained. The sample consisted of majority male (67.6%), single (46.2%) and employed (66%) patients. The most common type of trauma was traffic collision (63.9%). The mean age was 41.7 years. We found a significant correlation between PEth levels with AUDIT-C score (Spearman's r = 0.654; p <.0001). PEth had an area under the ROC curve of 0.885 to detect hazardous alcohol consumption (AUDIT-C score ≥ 6) and PEth ≥23.9 ng/mL cutoff point provided 91.2% of sensitivity and 78.4% of specificity. Twelve patients reported alcohol abstinence, but had quantifiable levels of PEth. PEth levels and AUDIT-C score had a moderate correlation in our population. PEth was useful to identify 12 cases of underreporting of alcohol consumption habits. PEth shows promising results, but more research is needed to identify the best screening tool for alcohol misuse in trauma patients. [ABSTRACT FROM AUTHOR]

In addition to currently used methods of gas chromatography with flame ionization detector or mass spectroscopy detection (GC–FID and GC–MS) for the analysis of seized heroin, a novel rapid high-performance liquid chromatography with tandem mass spectrometry (HPLC–MS/MS) method for detection and quantification of the main alkaloids was developed. This method for detection and quantification of heroin, papaverine, noscapine, and acetyl thebaol was validated and applied to analysis of seized heroin street samples. The method is rapid (6 min) and implies a low solvent consumption (0.75 mL min−1), suitable as an alternative method for GC–MS for heroin samples stored at elevated temperatures. The method was successfully tested on seized heroin samples. [ABSTRACT FROM AUTHOR]

The main sample preparation method for analysis of pesticide residues in fruits is QuEChERS. In this study, a novel sample preparation method using molecular complex-based dispersive liquid–liquid microextraction is introduced with detection of forchlorfenuron by high-performance liquid chromatography coupled with diode array and mass spectrometric detection. Sample treatment involves initial extraction of a 5 g sample with 3 mL acetonitrile, and then the selective concentration of the analyte is performed using 150 µL tributyl phosphate by forming intermolecular hydrogen bonds with the analyte. The extraction mechanism was proved using ATR-FTIR. Under the optimised conditions, recovery rates varied between 88% and 107% for various sample matrices spiked at three levels in the range 0.01–0.1 mg kg−1. Intra-day and inter-day repeatabilities were in the ranges of 2.2–8.0% and 1.6–9.5%, respectively. Detection limit and quantitation limit were 0.33 µg kg−1 and 1.09 µg kg−1 for diode-array detection; 0.01 µg kg−1 and 0.04 µg kg−1 for tandem mass spectrometry detection. This method was successfully applied for the analysis of 149 various fruits. The analyte was found in 4 of the 149 samples and the contents were not over the specific maximum residue limit established by domestic and international regulations. [ABSTRACT FROM AUTHOR]

In this study, fifty-four wheat flour and wheat-based products available on the Hungarian market were assessed for twelve mycotoxins. Prior to analysis, a multi-mycotoxin method using high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS) was developed and validated for wheat and wheat-based products. A simple extraction with acetonitrile/water/formic acid (79/20/1 v/v%) was used for sample preparation. The limits of quantitation (LOQ) were between 0.02 and 161 μg kg−1. Good linearity (r2 > 0.995) was achieved for all mycotoxins investigated. Recoveries varied between 88 and 120% at three concentration levels. Based on the low relative matrix effect (RSD < 0.15%) of the different wheat flour samples, matrix-matched calibration was used, which also proved its suitability in proficiency testing (z-scores: −0.6 for DON; +1.5 for OTA; −0.5 for ZEA). DON was the predominant mycotoxin, which contaminated 84% of the investigated samples. Metabolised forms of DON were found in spelt, durum flour and some wheat-based products (D3G in 4 samples, 15Ac-DON in 7 samples). T-2 and HT-2 were the second most frequently detected mycotoxins. All investigated samples complied with current European/Hungarian legislation. [ABSTRACT FROM AUTHOR]

Several components of mushroom compost (wheat straw, chicken manure) can be contaminated with mycotoxins posing food health risks to mushroom consumers. To assess the relevance of such contaminations high-throughput analytical methods are needed. In this study, two sample preparation approaches, dilute & shoot (D&S) and modified citrate buffered Quick, Easy, Cheap, Effective, Rugged, Safe (QuEChERS) were compared in terms of extraction efficiency and matrix effect in case of 13 mycotoxins in complex matrices–wheat straw, the growing media and button mushrooms (Agaricus bisporus)–of mushroom cultivation using high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). D&S method resulted in recoveries of LB medium, button mushroom and compost for ≥60% in case of all investigated mycotoxins except for DON-3G. However, using modified citrate buffered QuEChERS with 2% acidification of the extraction solvent showed the complete loss of strongly polar DON-3G and fumonisin B1 (FB1). The investigated matrices had suppressive effect on ionization in all target mycotoxins except for FB1. Regarding the use of isotopologues to compensate matrix effect, even U-[13C15]-DON and U-[13C24]-T-2 can also be used to quantify their related metabolites in the studied matrices, using internal standard method. [ABSTRACT FROM AUTHOR]

Artemether; a sesquiterpene lactone is widely used for the treatment of malaria as artemisinin-based combination therapy (ACT). The present work involves the development and validation of sensitive reversed-phase high-performance liquid chromatography (RP-HPLC) method for quantification of artemether (ART) in polymeric nanoparticles. ART was transformed to α, β-unsaturated decalones by pre-column acid treatment to enhance the sensitivity of chromophoric group lacking ART for quantification by HPLC-UV. Waters Spherisorb® 5 µm ODS(C18) column (4.6*250 mm) with gradient elution by mobile phase comprising of ACN and PBS (10 mM; pH 6.0) was used to separate acid-treated ART. The analysis was carried at λmax of 253 nm with 20 min and 20 µL run time and injection volume, respectively. The method was found to be linear in the concentration range of 0.5–10 µg mL−1 with 0.09 µg mL−1 and 0.27 µg mL−1 as LOD and LOQ respectively. Further, the method was also found to be specific for ART in presence of blank polymeric nanoparticles, accurate (% average recovery rate 101.7 ± 1.68%), precise (RSD <2%), and robust. The method was successfully used to determine % entrapment efficiency and in vitro release of ART-loaded polymeric nanoparticles with HPLC using a UV-visible detector. [ABSTRACT FROM AUTHOR]

A high-performance chromatographic method was developed to determine the fungicide kresoxim-methyl. Off-line photochemical derivatization was used to induce the formation of a stable and fluorescent product since the fungicide does not present natural fluorescence. Intense fluorescence at 370/430 nm was achieved by treating the analyte in solution at pH 6 to ultraviolet light for 45 s. The chromatographic conditions included isocratic elution with 50/50% (v/v) acetonitrile/water and the photochemical product appeared at a retention time of 7.2 min. The short and long term stabilities of the photoproduct were evaluated and variation of less than 5% was achieved. The limits of detection in water samples and in grapes samples were 0.019 mg kg−1 and 0.065 mg kg−1 of kresoxim- methyl residue, respectively. The linear response covered three orders of magnitude up to 10.6 mg kg−1 of kresoxim-methyl. The robustness was evaluated through a Box–Behnken experimental design showing the insignificance of all factors and their interactions. The potential interference of tebuconazole for the determination of kresoxim-methyl was studied. The use of the dispersive liquid-liquid microextraction (DLLME) allowed recoveries between 80% and 101% depending on concentration with the minimum generation of waste products. [ABSTRACT FROM AUTHOR]

Objectives: To analyze and compare concentrations of amino acids (AAs) and acylcarnitine (AC) profiles in maternal-fetal serum from women with preeclampsia (PE) and to assess their use as possible predictors of PE.Methods: This is a retrospective study in which we enrolled a total of 38 pregnant women and their offspring. Pregnant women with PE (n = 14) and healthy pregnant control subjects (n = 24) participated voluntarily in the study. Maternal blood and cord blood were tested using dry blood spot (DBS) specimens, and we detected concentrations of 18 types of AAs and 31 types of AC by using high-performance liquid chromatography tandem mass spectrometry (HPLC-MS), and compared metabolites between the groups. We used logistic regression modeling to estimate the association of each metabolite with development of PE.Results: Concentrations of most AAs and AC in PE mothers were significantly higher than those in the group of control mothers. Cord plasma concentrations of AC in most PE mothers were significantly higher than those in controls; however, in PE, levels of cord plasma concentrations of most AAs were significantly lower, except for Gly, compared with controls. Levels of most AAs and AC were lower in the control and PE groups, with a tendency for lower levels in maternal blood compared to cord blood. Receiver operating characteristics (ROC) and areas under the curves (AUC) analyses using these metabolites did not predict PE individually.Conclusions: Maternal-fetal levels of AAs and AC were associated with PE. But the use of metabolites did not constitute a reliable method for use as a biomarker in the diagnosis of PE. Further prospective studies are needed to clarify the roles of different metabolites involved in the mechanism underlying the development of PE. [ABSTRACT FROM AUTHOR]

It is crucial to develop practical procedures for the control and reduction of pesticide residues in oil productions from farm to dining table. In this study, the dissipation behaviors of typical fungicide from rapeseed to oil production were studied to reveal relationship among spraying stage, application dosage, household oil processing stage, and pesticide residues. In the field trials, rape plants were sprayed with carbendazim at three different dosages during flowering period. Transfer assessment of carbendazim residues from rapeseed to oil production during household oil processing via different press techniques was determined using high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC–MS/MS). The recoveries of carbendazim in rapeseed samples, meals after squeezing samples, and rapeseed oil samples ranged from 82.5% to 93.6% with relative standard deviations (RSDs) ＜5.2%. The validation results illustrated that the methods were reliable and sensitive. The average processing factor (PF) during household oil processing via hot press technique and cold press technique was 0.15 and 0.51, respectively. This study demonstrated that household oil processing could significantly reduce the pesticide residues, especially by hot press technique. [ABSTRACT FROM AUTHOR]

Acrylamide, a known carcinogen, is formed during preparation of food containing reducing sugar and asparagine. Because acrylamide exposure of the population is primarily through food, the maximum levels of acrylamide in food were set by the European Commission in 2017. Moreover, in the 2016 Korean Total Diet study, acrylamide showed the lowest margin of exposure among 23 food-processing-related chemicals, necessitating risk reduction options. Therefore, the objective of this study was to determine the variation of acrylamide content in different food items and identify the food categories, to provide options for risk management. Acrylamide was analysed using high-performance liquid chromatography coupled with tandem mass spectrometry in more than 1,000 processed food items. To estimate acrylamide exposure, the analytical data obtained herein and the food consumption data of Korean National Health and Nutrition Examination Survey from 2013 to 2017 were used. A non-parametric technique of a probabilistic model was used for exposure estimation. Confectioneries (here this category includes potato and similar savoury snacks) contained a wide range of acrylamide content. Particularly, the highest acrylamide content was detected in a tea made of Jerusalem artichoke. The presence of acrylamide in turmeric along with the Jerusalem artichoke was reported in this study for the first time. The main contributors of dietary acrylamide exposure were confectioneries for youths aged 3–18 years and coffee for adults aged 19–80 years. Therefore, risk management in confectionery and coffee could help reduce acrylamide exposure for Koreans. In addition, the mitigation strategies for food containing high acrylamide content, such as Jerusalem artichoke tea, are needed to reduce acrylamide exposure to loyal consumers. [ABSTRACT FROM AUTHOR]

The maximum residue limit (MRL) of emamectin benzoate in mango had not been legislated in China and no work had been done to determine the emamectin benzoate residue in mango. The aim of this study was to investigate the dissipation and terminal residues of emamectin benzoate in mango under field conditions and to assess its safe use. A high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) with modified QuEChERS for analysis of emamectin benzoate was established. It was shown that at fortified levels of 0.005, 0.02 and 0.1 mg/kg, the average recoveries were 72–102% with RSDs less than 8% for intra-day and 81–102% with RSDs less than 9% for inter-day. The half-life of emamectin benzoate in mango was 4.9 days and terminal residues mostly lower than LOQ (0.005 mg/kg) with PHIs of 5, 7 and 10 days except Sichuan province. The dietary exposure risk of emamectin benzoate on mango was negligible depending on the RQ value of 2.77–34.96%. Therefore, it would be unlikely to cause health problems if emamectin benzoate was applied according to the use pattern suggested by the manufacturers on the label. These results would be useful in establishing MRL and providing guidance on the safe use of emamectin benzoate. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) is a heavy metal used in industrial processes that impedes the growth of plants. Although intensive work has concentrated on the mechanism of rice under Cd stress, few studies compared the proteomic information on the mechanism between different cultivars. Different rice cultivars were screened and two cultivars, the japonica cultivar Bancanggengnuo (BCGN) and indica cultivar Yuzhenxiang (YZX) were selected to be the varieties for proteomic experiments. High-performance liquid chromatography – tandem mass spectrometry (HPLC-MS/MS) with an isobaric tag for relative and absolute quantitation (iTRAQ) was used to analyze the global protein profiles of these two cultivars. There were 109 and 209 differentially expressed proteins (DEPs) in the Cd treatment groups for BCGN and YZX respectively and 61 additional DEPs between cultivars after treatment. Pathway enrichment analysis showed that three pathways were altered in the cultivars, which affected photosynthesis and redox reactions. A total of 37 up- and 27 down-regulated proteins were identified in both cultivars exposed to Cd. The molecular regulatory network revealed that several proteins associated with carbohydrate metabolism, redox reaction and signal transduction were involved in and acted as the intersection point of disturbed metabolism. This is the first report on the comprehensive proteomic characterization of Cd-exposed leaf proteomes in rice. These findings may facilitate the unraveling molecular mechanism underlying Cd stress response in rice, and provide fundamental insights into the development of Cd-resistant rice cultivars. This work has explored the mechanism of Cd resistance at the protein level, which may be a novel target for improving the resistance of rice to this heavy metal. [ABSTRACT FROM AUTHOR]

Gynostemma pentaphyllum has gained increasing interest in recent years for its widespread use as a medicinal plant, dietary supplement, herbal tea, and vegetable in China. This herb possesses many beneficial functions, such as anti-tumor, anti-inflammatory, cholesterol lowering, strengthening of the immune system, and blood pressure regulating activities. However, due to an absence of information, the major material components of Gynostemma pentaphyllum remain unknown. A method for the comprehensive profiling of components in Gynostemma pentaphyllum is reported using high performance liquid chromatography – electrospray ionization – quadrupole time-of-flight tandem mass spectrometry (HPLC-ESI-QTOF-MS/MS) in this study. As a result, a total of 36 compounds including flavonoid glycosides and gypenosides were characterized or tentatively identified. Four gypenosides were tentatively identified as potentially new compounds in Gynostemma pentaphyllum. These results provided a reference for comprehensive characterization of ingredients in Gynostemma pentaphyllum and are significant for the utilization of Gynostemma pentaphyllum. [ABSTRACT FROM AUTHOR]

Lignans are a class of polyphenols considered to be phytoestrogens because of their oestrogenic/antiestrogenic activities and their plant origin. Few works have reported on the content of lignans in ground coffee, and most of them analysed a small number of samples. Hence, our aim was to quantify the content of three lignans, secoisolariciresinol, lariciresinol and matairesinol, in ground coffee by using high-performance liquid chromatography tandem mass spectrometry. Evaluation of acidic hydrolysis, methanolic extractions, and enzymatic digestions as extraction methods indicated that enzymatic digestion with Taka-diastase 2% was the best. When this method was applied to 30 different ground coffees, we found that SECO was the highest concentration lignan (84.4-257.8 μg kg-1), followed by LARI (26.1-91.5 μg kg-1). Moreover, comparison of lignan extraction yield in espresso coffee and ground coffee showed that these molecules seem to be completely extracted during espresso coffee percolation, since the extraction yield average was 95.2%. [ABSTRACT FROM AUTHOR]

Background and aims: Trimethylamine N-oxide (TMAO), a pro-atherosclerotic intestinal microbiota metabolite, has mechanistic links to atherosclerosis development and cardiovascular diseases. In this study, we aimed to investigate whether serum TMAO levels could predict early neurological deterioration (END) after acute ischemic stroke. Methods: We prospectively recruited patients with first-ever ischemic stroke and hospitalized within 24 h of symptoms onset during Mar 2018 to Mar 2019. Plasma TMAO levels were quantified using stable isotope dilution high-performance liquid chromatography with tandem mass spectrometry after admission. END was defined as an increase in the total National Institutes of Health Stroke Scale by 2 or more points within 3 days. Results: Of the 362 patients included, END was diagnosed in 97 subjects (26.8%). The median TMAO concentrations were 4.8 μmol/L, with tertile levels as follows: first tertile (<3.9 μmol/L), second tertile (3.9–5.6 μmol/L), and third tertile (>5.6 μmol/L). Patients with END showed higher levels of TMAO (median 5.0 vs. 4.5 μmol/L, P = 0.005) at admission. In univariate logistic analysis, elevated plasma levels of TMAO [odd ratios for highest tertile vs. lowest tertile, 2.14; 95% confidence interval, 1.19–3.82] was a significant predictor of END in patients with ischemic stroke. This association remained significant after controlling for confounders in multivariate logistic analysis. Multiple-adjusted spline regression model further confirmed the dose–response relationship between TMAO levels and END (P < 0.001 for linearity). Conclusions: Our study indicated that increasing TMAO levels at admission might be associated with END after acute ischemic stroke. [ABSTRACT FROM AUTHOR]

Eliglustat tartrate is an oral inhibitor of glucosylceramide synthase used in the therapy of Gaucher's disease. The drug was subjected to forced degradation study using various stress parameters like acidic, basic, oxidation, photolysis and thermal conditions. The drug showed significant degradation under acidic and peroxide stress conditions, however the drug remained stable under basic, neutral, thermal and photolytic stress conditions. The present research reports the characterization of degradation products of Eliglustat by liquid chromatography-tandem mass spectrometry(HRMS) and 2D-NMR techniques along with the development and validation of stability indicating ultra performance liquid chromatographic method for determination and quantification of Eliglustat drug in presence of characterized impurities. Two novel degradation products (DP1 & DP-2) were found under stress conditions. These degradation products were isolated using preparative high performance liquid chromatography. The structure of the DP-1 was identified as the cis- diastereoisomer of Eliglustat and DP-2 as the N-Oxide impurity of Eliglustat which were not reported in any of the literature. The chromatographic method was developed on UPLC to achieve separation of degradation products and Eliglustat using Acquity; BEH; C-18; 100 x 2.1 mm; 1.7 μm column within a short run time of 8.0 minutes. The method was validated for specificity, precision, linearity and accuracy. The quantitation limits obtained were in the range of 0.3-3.0 μg ml-1 for the characterized impurities. This method is compatible to LCMS analysis which enables to identify the unknown impurities formed in the process. [ABSTRACT FROM AUTHOR]

Tacrolimus has been widely applied to prevent organ rejection after transplantation. However, the conventional pharmaceutical formulation of tacrolimus limits its applications in ocular therapy due to its hydrophobicity and low corneal penetrability. We optimized tacrolimus-loaded methoxy poly (ethylene glycol-block-poly (d, l)-lactic-co-glycolic acid) nanoparticles (TAC-NPs) by simple and effective nanotechnology as a drug delivery system for corneal graft rejection to overcome these drawbacks. The prepared TAC-NPs were 82.9 ± 1.3 nm in size, and the drug loading and encapsulation efficiency were 8.01 ± 0.23% and 80.10 ± 2.33%. Furthermore, New Zealand rabbits were used to analyze the single-dose pharmacokinetics of the TAC-NPs using high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). In rats with allogenic penetrating keratoplasty, the administration of TAC-NPs dispersion drops improved the TAC concentrations in the aqueous humor and cornea, consistent with a significantly higher effective inhibition of IL-2, IL-17, and VEGF expression compared with conventional 0.1% tacrolimus drops. Meanwhile, we also compared two different topical administration methods (including eye drop and subconjunctival injection) of TAC-NPs to maximize the sustained release characteristic of NPs. In summary, the small-sized TAC-NPs enhanced transcorneal permeation and absorption of TAC and more effectively inhibited corneal allograft rejection, which indicated that biodegradable polymeric nanomaterials-based drug delivery system had great potential for improving the clinical therapy efficacy of hydrophobic drugs. [ABSTRACT FROM AUTHOR]

A modified hollow-fiber-supported dispersive liquid-liquid microextraction (HF-DLLME) method was developed for the determination of aflatoxins and ochratoxin A in food samples. The various parameters affecting the efficiency of extraction, such as pH, salt addition, extraction time, stirring rate, desorption time, type and volume of extractant and disperser solvents were carefully studied and optimized using two step strategies. The linearity of the evaluated results was 0.1 to 30 μg L−1 for aflatoxins and 0.1 to 20 μg L−1 for ochratoxin A, with regression coefficients (R2) exceeding 0.9990. The precision was satisfactory with relative standard deviation values less than 11%. The method accuracy was within the recommended range from 70% to 120% and analyte accuracy between 83% and 101%. The limits of detection and quantification were in the range from 0.04 to 0.06 μg L−1 and 0.08 to 0.13 μg L−1, respectively, for multi-aflatoxins, and 0.02 to 0.04 µg L−1 and 0.08 to 0.10 µg L−1, respectively, for ochratoxin A. The developed method was successfully applied for the determination of mycotoxins in food samples. [ABSTRACT FROM AUTHOR]

Chromatographic techniques were used to prepare rosmarinic acid rich extract from Orthosiphon aristatus. Such extract is highly required for herbal product development because of its remarkable bioactivities. Therefore, the plant crude extract was fractionated using solvent mixture, ethyl acetate and ethanol in column chromatography. The solvent system was developed using thin layer chromatography. The results found that 60-99.9% ethyl acetate in ethanol could separate rosmarinic acid with the retention factor (Rf) ranged from 0.2–0.3. Of the solvent systems, 70% ethyl acetate could produce the highest yield of rosmarinic acid, 4.5% w/w with 100% purity. The concentration of rosmarinic acid was quantified by high performance liquid chromatography integrated with tandem mass spectrometry. The subsequent combined fractions could recover 70% of total rosmarinic acid from crude extract. The bed height of the silica gel packed column increased from 16 to 24 and 32 cm did not affect the performance of rosmarinic acid elution in column chromatography. The silica gel absorbent could be repeatedly used up to five times to recover rosmarinic acid from crude extract. Column chromatography can be used to recover rosmarinic acid (>85%) using the binary solvent system (70% ethyl acetate:30% ethanol) effectively. [ABSTRACT FROM AUTHOR]

In this study, a new and accurate method based on ultra-high performance liquid chromatography (UHPLC) with electrospray ionisation tandem triple quadrupole mass spectrometry (MS/MS) was developed and validated for the determination of josamycin in three kinds of feeds (compound, concentrated and premix feeds). The optimised sample pretreatment procedure included extracting from the matrix with a mixture of methanol and acetonitrile (1:1, v/v) followed by drying under nitrogen and redissolving in phosphate buffer solution (pH = 8, 0.1 mol/L) followed by purifying using HLB cartridges. Validation of the method was carried out in three different matrices (compound, concentrated and premix feed) by recovery experiments, using samples spiked at concentration levels of 20, 100 and 200 μg/kg. Satisfactory recoveries from 82.4% to 93.0%, with RSDs lower than 17.4% under intermediate precision conditions were obtained in all feed matrices tested. The developed method was applied to commercially samples and josamycin was found frequently in feed containing kitasamycin. [ABSTRACT FROM AUTHOR]

Several Bauhinia species are widely used in Southern South America in the treatment of infections, pain and several diseases including diabetes. Flavonoid compounds based on quercetin and kaempferol glycoside derivatives are believed to be responsible for their therapeutic properties. To investigate this, we have studied two native species from Argentina: B. uruguayensis (BU) and B. forficata subsp. pruinosa (BF). We have analyzed the major polyphenol components in hydro-methanolic extracts of leaves, by high performance liquid chromatography tandem mass spectrometry. Chromatographic analysis yielded five main compounds in BF, corresponding to rutinosides and rhamnosides derivatives of kaempferol and quercetin, which are considered chemotaxonomic markers and responsible for antioxidant activity. The presence of kaempferitrin, an antidiabetic agent, has been confirmed. In extracts of BU, four major compounds were identified as rhamnosides and galloyl derivates from quercetin and kaempferol. One of these compounds, quercitrin-3-rhamnoside may confer anti-inflammatory and analgesic properties to BU extracts. [ABSTRACT FROM AUTHOR]

Familial adenomatous polyposis (FAP) is an autosomal dominantly inherited intestinal polyposis syndrome accounting for about 1% of colorectal cancers (CRC). Despite increasing researches on the molecular pathogenesis of CRC, we are still unclear about metabolic pathways and alterations probably involved in the development of CRC. To obtain new insights into the mechanisms underlying APC mutation and to elucidate the mechanisms of CRC development, we performed to identify the potential metabolites in FAP based on metabolomic strategy. Serum metabolites from FAP patients (n = 30) and healthy individuals (n = 34) were detected and qualified using Ultra Performance Liquid Chromatography and Tandem Mass Spectrometry (UPLC− MS/MS). 118 metabolites were identified with statistical tests of orthogonal partial least-squares-discriminant analysis (OPLS−DA), with the conditions of variable importance in projection (VIP) >1, p < 0.05 using the Mann−Whitney U test, and fold change (FC) ≥2 or ≤0.5. OPLS-DA model was useful for distinguishing FAP patients from healthy controls. Unique metabolic signatures were pooled in FAP patients covering tricarboxylic acid (TCA) cycle, amino acids metabolism, vitamin D, fatty acids metabolism, and bile acids (BAs) metabolism. Our results demonstrated that metabolites alterations in FAP can be helpful for further analysis of metabonomics induced by APC mutation, and these alterations might be involved in the progress of intestinal carcinogenesis. [ABSTRACT FROM AUTHOR]

A simple, accurate, precise and specific high performance liquid chromatography mass spectrometric method for the estimation of doxazosin in human plasma (K2EDTA), using doxazosin D8 as an internal standard was developed and validated. The samples are prepared by liquid-liquid extraction method by using tetra butyl methyl ether, followed by freezing and evaporation of the organic solvent. The remaining dry residue is redissolved in mobile phase and analyzed by LC-MS-MS with positive electro spray ionization using the multi reaction monitoring mode. An unisol C18 (150 X 4.6) mm, 5 μm, 100 A° column, a mobile phase composed of acetonitrile and 0.05 % ammonia solution in HPLC grade water with isocratic elution, and a flow rate of 1.000 mL/minute with split ratio 1:1 and the column oven temperature was set 40±2°C. The elution time for doxazosin and internal standard were 2 min. All the parameters were maintained for the study. This method is validated for 0.301 ng/mL to 75.179 ng/mL concentration range. The method is applied for doxazosin plasma levels following single administration of doxazosin mesylate tablets to human in the fed state. [ABSTRACT FROM AUTHOR]

Two hundred and seventy six mulberry juice samples were analyzed by high-performance liquid chromatography with diode-array detection quadrupole time-of-flight tandem mass spectrometry to identify the major polyphenols in the representative mulberry fruit cultivar Da10. Using FRAP, ABTS, and DPPH assays, total phenolic contents and antioxidant capacities of 276 mulberry juice samples from four provinces in China were found to be within the following ranges: 412.55–1471.86 mg/L gallic acid equivalent, 37.90–361.75 mmol/mL ferrous sulfate equivalent, 46.12–342.13 mmol/mL Trolox equivalent, and 7.30–216.41 mmol/mL ascorbic acid equivalent. Cluster analysis separated the cultivars into two groups. One group consisted of samples from Guangdong, Guangxi, and Hainan Provinces, which had high phenolic contents and antioxidant capacities. The other group consisted of samples from Xinjiang Province, which had low phenolic contents and antioxidant capacities. Antioxidant activity and phenolic content were correlated. Flavonoids were the main polyphenols of "Da10". In addition to free phenolic compounds, various bound phenolic compounds were identified. This work provides a large dataset characterizing different mulberry cultivars for deeper research. "45–7", "qianshan3" and "guoxuan04-129" were superior cultivars based on their high phenolic contents and antioxidant capacities. The results of this study support further research into mulberry use in human food and healthcare industries. [ABSTRACT FROM AUTHOR]

Seventeen quinolone antibiotics were determined in cows' milk. A method of high sensitivity, selectivity and accuracy was developed. Accuracy (trueness and precision), linearity, sensitivity, selectivity, decision limit and detection capability were established following the recommendations of the Commission Decision 2002/657/EC and the Food and Drug Administration (FDA) guideline. The use of polar stir-bar sorptive extraction (SBSE) prior to UHPLC-MS/MS analysis is proposed. The variables that affect SBSE were optimised using multivariate optimisation strategies. The ionic strength, the extraction time and the sample volume were studied. pH and stir-bar coating (polydimethylsiloxane, PDMS, and polyethyleneglycol modified silicone, PEG) were studied. PEG showed the best extraction yield at pH 6. For validation, a matrix-matched calibration and a recovery assay were carried out. Limits of quantification from0.5 µg kg-1 for nalidixic acid, flumequine and piromidic acid, to 4.0 µg kg-1 for sarafloxacin were calculated. The precision (%, RSD) was lower than 15%for all antibiotics. Recoveries in fortified samples were between 88 and 114%. [ABSTRACT FROM AUTHOR]

In the present study, 100 commercial breads and biscuits were investigated for the occurrence of deoxynivalenol (DON) and its acetylated derivatives 3-acetyldeoxynivalenol (3-Ac-DON) and 15-acetyldeoxynivalenol (15-Ac-DON). The target mycotoxins were determined by isotope dilution ultrahigh performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS). DON was determined in 95% of the test samples with a mean value of 153.3 µg/kg. Compared with DON, 3-Ac-DON and 15-Ac-DON were far less frequently detected, with mean values of 1.14 and 0.37 µg/kg, respectively. The estimated daily intakes of the sum of DON and its derivatives in breads and biscuits were 0.0059 and 0.0313 µg/kg bw/day, respectively, which was within the group provisional tolerable daily intake of 1.0 µg/kg bw/day set by the Joint FAO/WHO Expert Committee on Food Additives. In the future, systematic monitoring programmes of DON and its derivatives in relevant foodstuffs are still necessary for food safety and human health. [ABSTRACT FROM AUTHOR]

Modern treatments of Parkinson's disease include the use of carbidopa and droxidopa along with levodopa that demonstrates the necessity for their binary and simultaneous determination in pharmaceutical tablets and biological matrices. This study presents a rapid, accurate, and precise method for the simultaneous determination of these analytes by liquid chromatography-tandem mass spectrometry method for the first time. Accordingly, performances of two types of analytical columns, namely, octadecylsilane and hydrophilic interaction liquid chromatographic columns, were tested and better resolution was obtained with the former. The pH of aqueous mobile phase (0.5% formic acid) was adjusted to 2.3 to ensure the analytes were in molecular form. Calibration graphs were obtained using multiple reaction mode and detection limits were in the region from 0.002 to 0.007 μM for both columns. The method developed was applied for quality control samples and tablets and satisfactory recovery values from 100 to 106% were obtained. [ABSTRACT FROM AUTHOR]

Amnesic shellfish poisoning is a potentially lethal human toxic syndrome which is caused by domoic acid (DA), a neurotoxin produced by marine phytoplankton, principally fromPseudonitzschiagenus. In this report, a method to identify and quantify the DA toxin, with simultaneous identification of its photodegradation products, has been developed. It uses an ultra high performance liquid chromatography coupled to a quadrupole-time-of-flight tandem mass spectrometer (UHPLC–QTOF) after solid-phase extraction (SPE). An unambiguous identification of DA was carried out by considering both the retention time of DA in UHPLC and the exact mass of protonated DA molecule ([M + H]+ = 312.1447 m/z) and of the most intense fragment ion (m/z 266.1391). The quantification was conducted using protonated DA molecule with protonated Glafenin as internal standard, obtaining a limits of detection of 0.75 µg L−1. Large screening with UHPLC–QTOF could also give structural information about degradation products of DA present in samples after UV-irradiation. This method was applied for the determination of DA in complex liquid samples after SPE and is applicable for environmental monitoring of this toxic substance in the aquatic environment. [ABSTRACT FROM PUBLISHER]

Voriconazole is used to prevent invasive pulmonary aspergillosis. However, little is known about the concentrations of voriconazole in human lung epithelial cells (A549), which is the target for preventing invasive pulmonary aspergillosis. The goal of this study was to develop a high-performance liquid chromatography–tandem mass spectrometry method to quantify voriconazole in A549 cells. A triple-quadrupole mass spectrometer in selected reaction monitoring mode was used with positive electrospray ionization. The total duration of each run was 5 min. The calibration curves fit a least squares model for the voriconazole concentration ranging from 0.625 to 160 ng/mL. Intraday and interday coefficients of variation were less than 10%. Recoveries at the concentrations of the quality control samples where greater than 85%, and the matrix effects showed that the ratios of the peak response exhibited a 15% suppression of the signal in the matrix compared to water. Voriconazole may penetrate A549 cells. However, the voriconazole uptake was slow in A549 cells, reaching a plateau at 2 h, where the dose-dependent intracellular voriconazole concentrations were 1.98 ± 0.38, 4.43 ± 0.54, and 8.14 ± 0.52 ng/mg protein for extracellular voriconazole concentrations of 5, 10, and 20 µg/mL, respectively. The uptake of voriconazole by A549 cells was linear at extracellular concentrations from 0 to 20 µg/mL. This study established a rapid and sensitive method suitable for determining voriconazole in A549 cells and described the kinetic properties of the absorption of voriconazole by A549 cells. [ABSTRACT FROM PUBLISHER]