GHB (γ-hydroxybutyrate) is becoming popular recreational drugs. As a result of its strong sedative and amnesiac effects, GHB has been implicated in a number of DFSA cases. The natural presence of GHB in the human b...GHB (γ-hydroxybutyrate) is becoming popular recreational drugs. As a result of its strong sedative and amnesiac effects, GHB has been implicated in a number of DFSA cases. The natural presence of GHB in the human body and its rapid elimination after ingestion make it difficult to detect and to evaluate its roles in suspected GHB-facilitated assaults. The paper describes an analytical method for the determination of GHB in urine using LC-MS/MS. Samples were acidified by ammonium chloride solution and extracted with ethyl acetate, and then the extracts were analysed by LC-MS/MS. The limit of detection was 0.05 p.g/mL (S/N = 3). The intra- and inter-day precision was within 10.0% at three concentrations. The methods were found to be sensitive, accurate, rapid and suitable for the forensic toxicology to test GHB in real cases.展开更多
The cis and trans isomers separation of 2-butene-1,4-diol and lafutidine were studied by HPLC on two kinds of chiral columns: (S,S)-Whelk-O 1 and ChiraSpher. The isomers of 2-butene-1,4-diol can be separated on both c...The cis and trans isomers separation of 2-butene-1,4-diol and lafutidine were studied by HPLC on two kinds of chiral columns: (S,S)-Whelk-O 1 and ChiraSpher. The isomers of 2-butene-1,4-diol can be separated on both chiral columns while the isomers of lafutidine can only be resolved on ChiraSpher column. The influence of different type and amount of mobile phase modifier on the isomers separation was extensively studied. The resolution of cis and trans isomers of 2-butene-1,4-diol was 2.61on (S,S)-Whelk-O 1 column with hexane-ethanol (97:3, v/v) as the mobile phase. The resolution of lafutidine was 1.89 on ChiraSpher column with hexane-ethanol-THF-diethylamine (92:3:5:0.1, v/v/v/v) as the mobile phase. LC-MS methods were developed to identify the isomer peaks.展开更多
We investigated the metabolism of pectenotoxins in brown crabs(Cancer pagurus).The crabs were fed with blue mussels(Mytilus edulis) for 21 d then depurated for 42 d.We extracted the toxins from the digestive glands of...We investigated the metabolism of pectenotoxins in brown crabs(Cancer pagurus).The crabs were fed with blue mussels(Mytilus edulis) for 21 d then depurated for 42 d.We extracted the toxins from the digestive glands of contaminated crabs,uncontaminated crabs(control group),and the meat of blue mussels using methanol.Extracts of the crab digestive glands were fractionated by liquid-liquid partitioning and solid phase extraction.The fractions were analyzed by liquid chromatography coupled with tandem mass spectrometry(LC-MS/MS) and liquid chromatography coupled with ion-trap mass spectrometry(LC-MSn).We detected a new PTX-like compound,designated as metabolite-1.The MS2 mass spectrum of the metabolite-1 [M+Na]+ ion at m/z 897.5 revealed fragment ions at m/z 853.5 and 555.5,typical of those exhibited by other pectenotoxins.展开更多
Artemisinin is a potent anti-malarial drug isolated from traditional Chinese medicinal herb, Artemisia annua. The objective of this study was to develop and validate a sensitive and specific LC-MS/MS method for the de...Artemisinin is a potent anti-malarial drug isolated from traditional Chinese medicinal herb, Artemisia annua. The objective of this study was to develop and validate a sensitive and specific LC-MS/MS method for the determination of artemisinin in rat plasma using amlodipine as Internal Standard. The method consist of a simple liquid-liquid extraction with methyl tertiary butyl ether (MTBE) with subsequent evaporation of the supernatant to dryness followed by the analysis of the reconstituted sample by LC-MS/?vIS with a Z-spray atmospheric pressure ionization (API) interface in the positive ion-multiple reaction monitoring mode to monitor precursor--〉product ions of m/z 282.70--〉m/z 209.0 for artemisinin and m/z 408.9--〉m/z 237.0 for amlodipine respectively. The method was linear (0.999) over the concentration range of 7.8-2000 ng/mL in rat plasma. The intra and inter-day accuracy were measured to be within 94-104.2% and precision (CV) were all less than 5%. The extraction recovery means for internal standard and all the artemisinin concentrations used were between 82-85%.展开更多
文摘GHB (γ-hydroxybutyrate) is becoming popular recreational drugs. As a result of its strong sedative and amnesiac effects, GHB has been implicated in a number of DFSA cases. The natural presence of GHB in the human body and its rapid elimination after ingestion make it difficult to detect and to evaluate its roles in suspected GHB-facilitated assaults. The paper describes an analytical method for the determination of GHB in urine using LC-MS/MS. Samples were acidified by ammonium chloride solution and extracted with ethyl acetate, and then the extracts were analysed by LC-MS/MS. The limit of detection was 0.05 p.g/mL (S/N = 3). The intra- and inter-day precision was within 10.0% at three concentrations. The methods were found to be sensitive, accurate, rapid and suitable for the forensic toxicology to test GHB in real cases.
文摘The cis and trans isomers separation of 2-butene-1,4-diol and lafutidine were studied by HPLC on two kinds of chiral columns: (S,S)-Whelk-O 1 and ChiraSpher. The isomers of 2-butene-1,4-diol can be separated on both chiral columns while the isomers of lafutidine can only be resolved on ChiraSpher column. The influence of different type and amount of mobile phase modifier on the isomers separation was extensively studied. The resolution of cis and trans isomers of 2-butene-1,4-diol was 2.61on (S,S)-Whelk-O 1 column with hexane-ethanol (97:3, v/v) as the mobile phase. The resolution of lafutidine was 1.89 on ChiraSpher column with hexane-ethanol-THF-diethylamine (92:3:5:0.1, v/v/v/v) as the mobile phase. LC-MS methods were developed to identify the isomer peaks.
基金Supported by Norwegian International Education Funding,Quota Program
文摘We investigated the metabolism of pectenotoxins in brown crabs(Cancer pagurus).The crabs were fed with blue mussels(Mytilus edulis) for 21 d then depurated for 42 d.We extracted the toxins from the digestive glands of contaminated crabs,uncontaminated crabs(control group),and the meat of blue mussels using methanol.Extracts of the crab digestive glands were fractionated by liquid-liquid partitioning and solid phase extraction.The fractions were analyzed by liquid chromatography coupled with tandem mass spectrometry(LC-MS/MS) and liquid chromatography coupled with ion-trap mass spectrometry(LC-MSn).We detected a new PTX-like compound,designated as metabolite-1.The MS2 mass spectrum of the metabolite-1 [M+Na]+ ion at m/z 897.5 revealed fragment ions at m/z 853.5 and 555.5,typical of those exhibited by other pectenotoxins.
文摘Artemisinin is a potent anti-malarial drug isolated from traditional Chinese medicinal herb, Artemisia annua. The objective of this study was to develop and validate a sensitive and specific LC-MS/MS method for the determination of artemisinin in rat plasma using amlodipine as Internal Standard. The method consist of a simple liquid-liquid extraction with methyl tertiary butyl ether (MTBE) with subsequent evaporation of the supernatant to dryness followed by the analysis of the reconstituted sample by LC-MS/?vIS with a Z-spray atmospheric pressure ionization (API) interface in the positive ion-multiple reaction monitoring mode to monitor precursor--〉product ions of m/z 282.70--〉m/z 209.0 for artemisinin and m/z 408.9--〉m/z 237.0 for amlodipine respectively. The method was linear (0.999) over the concentration range of 7.8-2000 ng/mL in rat plasma. The intra and inter-day accuracy were measured to be within 94-104.2% and precision (CV) were all less than 5%. The extraction recovery means for internal standard and all the artemisinin concentrations used were between 82-85%.