A sensitive liquid chromatography-electrospray ionization-tandem mass spectrometric (LC-MS/MS) method for the simultaneous determination of aspirin (ASA) and its metabolite salicylic acid (SA) in human plasma has been...A sensitive liquid chromatography-electrospray ionization-tandem mass spectrometric (LC-MS/MS) method for the simultaneous determination of aspirin (ASA) and its metabolite salicylic acid (SA) in human plasma has been developed and validated.The plasma ASA and SA were extracted using a liquid-liquid extraction (LLE) and the sample extract was injected onto the LC-MS/MS system.The limits of quantitation(LLOQ) for ASA and SA are both 25 ng/mL.This method allowed the reproducible and accurate quantification with the concentration rang of 25-10 000 ng/mL.This method could be applied to the quantitation aspirin and salicylic acid in human plasma.展开更多
HPLC-MS/MS methods were developed to determine 19 kinds of free amino acids in human serum. API 4000 and Quattro Ultima HPLC-MS/MS systems were used in this study. The established method proved to be fast and specific...HPLC-MS/MS methods were developed to determine 19 kinds of free amino acids in human serum. API 4000 and Quattro Ultima HPLC-MS/MS systems were used in this study. The established method proved to be fast and specific.It can be applied to determine 19 kinds of amino acids simultaneously and also can be used in the disease screening studies associated with amino acids disorders.展开更多
A method for measure the plasma concentration of ibuprofen and pseudoephedrine was established by liquid chromatography-tandem mass spectrometr pseuy (LCMS-MS). The chromatography column is Alltima C18 column (50min&#...A method for measure the plasma concentration of ibuprofen and pseudoephedrine was established by liquid chromatography-tandem mass spectrometr pseuy (LCMS-MS). The chromatography column is Alltima C18 column (50min×2. 1mm×3μm).The mobile phase consisted of methonal-5 and acetate ammonium. The flow rate is 0.2mL/min. Detection was performed using electrospray ionization (ESI) interface in multiple reactions monitoring (MRM) mode. The assay procedure was shown to produce linear calibration curves over the range 250 to 50000μg/L of ibuprofen,2.5 to 500μg/L of pseudoephedrine in plasma. The limit of detection is 250μg/L of ibuprofen, 2.5μg/L for pseudoephedrine. The extraction recovery of ibuprofen and pseudoephedrine was 50% and 18%, respectively. The linearity of standard curves is in the range of 0. 990-1. 000. Inter- and intra-day precision (RSD%) is all within ±15 % (n = 5) and the accuracy is within 99.3%-103.2% (n=30). The method is sufficiently sensitive, specific, accurate, precise, stable, and fast. Key words: high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS); multiple reactions monitoring (MRM); electrospray ionization (ESI).展开更多
Here we report a sensitive LC-MS/MS method capable of quantifying n-Butylphthalide (NBP) down to 0.5 ng/mL in rat and human hepatic microsome incubating solutions.The method was validated over linear range of 0.5-4 00...Here we report a sensitive LC-MS/MS method capable of quantifying n-Butylphthalide (NBP) down to 0.5 ng/mL in rat and human hepatic microsome incubating solutions.The method was validated over linear range of 0.5-4 000 ng/mL using diazepam as the internal standard.Compound was simply prepared by protein precipitation method and analyzed on the LC-MS/MS,which was an API-4000 system equipped with ESI interface and a Symmetry C18 column.The between-day and within-day precision and accuracy of quality control samples were ≤9.3% RSD% and ≤3.3% RE%.Sample stability (Stock solution,freeze/thaw,bench-top,short-term and long-term stability) were also investigated.This method has been applied to drug-drug interaction study of NBP in rat and human hepatic microsome incubating solutions.展开更多
Quantitative determination of QT341 in human plasma was explored by mass spectrometry.API 3000 LC-MS/MS were used in this study.The established method proved to be fast and specific.Some ideas about the quantitative a...Quantitative determination of QT341 in human plasma was explored by mass spectrometry.API 3000 LC-MS/MS were used in this study.The established method proved to be fast and specific.Some ideas about the quantitative analysis of the drug in the treatment of ischemic heart disease and the method for the solid-phase extraction from the human plasma were introduced in this paper.展开更多
文摘A sensitive liquid chromatography-electrospray ionization-tandem mass spectrometric (LC-MS/MS) method for the simultaneous determination of aspirin (ASA) and its metabolite salicylic acid (SA) in human plasma has been developed and validated.The plasma ASA and SA were extracted using a liquid-liquid extraction (LLE) and the sample extract was injected onto the LC-MS/MS system.The limits of quantitation(LLOQ) for ASA and SA are both 25 ng/mL.This method allowed the reproducible and accurate quantification with the concentration rang of 25-10 000 ng/mL.This method could be applied to the quantitation aspirin and salicylic acid in human plasma.
文摘HPLC-MS/MS methods were developed to determine 19 kinds of free amino acids in human serum. API 4000 and Quattro Ultima HPLC-MS/MS systems were used in this study. The established method proved to be fast and specific.It can be applied to determine 19 kinds of amino acids simultaneously and also can be used in the disease screening studies associated with amino acids disorders.
文摘A method for measure the plasma concentration of ibuprofen and pseudoephedrine was established by liquid chromatography-tandem mass spectrometr pseuy (LCMS-MS). The chromatography column is Alltima C18 column (50min×2. 1mm×3μm).The mobile phase consisted of methonal-5 and acetate ammonium. The flow rate is 0.2mL/min. Detection was performed using electrospray ionization (ESI) interface in multiple reactions monitoring (MRM) mode. The assay procedure was shown to produce linear calibration curves over the range 250 to 50000μg/L of ibuprofen,2.5 to 500μg/L of pseudoephedrine in plasma. The limit of detection is 250μg/L of ibuprofen, 2.5μg/L for pseudoephedrine. The extraction recovery of ibuprofen and pseudoephedrine was 50% and 18%, respectively. The linearity of standard curves is in the range of 0. 990-1. 000. Inter- and intra-day precision (RSD%) is all within ±15 % (n = 5) and the accuracy is within 99.3%-103.2% (n=30). The method is sufficiently sensitive, specific, accurate, precise, stable, and fast. Key words: high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS); multiple reactions monitoring (MRM); electrospray ionization (ESI).
文摘Here we report a sensitive LC-MS/MS method capable of quantifying n-Butylphthalide (NBP) down to 0.5 ng/mL in rat and human hepatic microsome incubating solutions.The method was validated over linear range of 0.5-4 000 ng/mL using diazepam as the internal standard.Compound was simply prepared by protein precipitation method and analyzed on the LC-MS/MS,which was an API-4000 system equipped with ESI interface and a Symmetry C18 column.The between-day and within-day precision and accuracy of quality control samples were ≤9.3% RSD% and ≤3.3% RE%.Sample stability (Stock solution,freeze/thaw,bench-top,short-term and long-term stability) were also investigated.This method has been applied to drug-drug interaction study of NBP in rat and human hepatic microsome incubating solutions.
文摘Quantitative determination of QT341 in human plasma was explored by mass spectrometry.API 3000 LC-MS/MS were used in this study.The established method proved to be fast and specific.Some ideas about the quantitative analysis of the drug in the treatment of ischemic heart disease and the method for the solid-phase extraction from the human plasma were introduced in this paper.
