The probable carcinogenic nitrosamine impurities, such as N-nitrosodiethylamine (NDEA) and N-nitrosodimethylamine (NDMA), have been detected from various pharmaceuticals in recent years. The sensitive chromatographic methods, including liquid chromatography (LC) and gas chromatography (GC), have been applied for analyzing nitrosamines in the pharmaceutical substrates, such as sartans, ranitidine and metformin. In comparison of LC, the efficacy of GC for analyzing multiple nitrosamines in diverse pharmaceuticals will be limited or attenuated owing to the chemical properties of target analytes or matrix hinderance of pharmaceutical substrates.
View Article and Find Full Text PDFNew psychoactive substances are being launched in the drug market at a rapidly growing pace. More than 950 new psychoactive substances have been reported to the United Nations Office on Drugs and Crime. The development of new psychoactive substance abuse has drawn risks on public health and safety.
View Article and Find Full Text PDFSynthetic cathinones, which are a group of β-keto analogs of phenethylamine, have been reported as the most emerging new psychoactive substances in the past decade. The quantity and variety of synthetic cathinones have continued to increase, which poses considerable risks to public health and social security. In this study, an analytical method based on liquid chromatography-tandem mass spectrometry (LCMS/MS) was established for the simultaneous determination of 73 synthetic cathinones and related metabolites in urine.
View Article and Find Full Text PDFAn incident of sartan medicine contamination was notified by Europe in June 2018. The contaminant was identified as a probable carcinogenic nitrosamine and the recalls of sartan medicines were soon made. Since then, more nitrosamine contaminants in sartan medicines were reported.
View Article and Find Full Text PDFAn approach was developed to enhance the efficiency for the bioconversion of 1-(3-hydroxyphenyl)-2-(methyamino)-ethanone to (R)-phenylephrine. The strain Serratia marcescens N10612, giving the benefit of 99% enantiomeric excess in (R)-PE conversion, was used. The fermentation was devised to harvest cells with high hydrophobic prodigiosin content inside the cells.
View Article and Find Full Text PDFThe strain Serratia marcescens N10612 is used to perform the bioconversion of 1-(3-hydroxyphenyl)-2-(methyamino)-ethanone (HPMAE) to (R)-phenylephrine ((R)-PE), which is an ephedrine drug substitute. The use of an ultrasound approach is found to improve the efficiency of the (R)-PE bioconversion. The optimization of the (R)-PE bioconversion is carried out by means of statistical experiment design.
View Article and Find Full Text PDFIn this study, the cell surface expression system was the first time used to directly produce extracellular enzyme. In the plasmid construction, the truncated ice nucleation protein (INP) was fused with intein (INT) and target protein, D-hydantoinase (DHTase), to form the INP-INT-DHTase gene. The plasmid containing this gene was transformed into Escherichia coli ER2566 cells.
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