کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1213792 | 1494123 | 2012 | 8 صفحه PDF | دانلود رایگان |
Methotrexate (MTX) is currently one of the most widely used drugs for treatment of rheumatoid arthritis (RA) through polyglutamation of methotrexate polyglutamates (MTXPGs), a process attaching sequential γ-linked glutamic residues to MTX. A new and sensitive LC/MS/MS method was developed and validated for determination of whole-blood MTX and total MTX (MTX + MTXPGs), and then concentration of MTXPGs was calculated. To determine whole-blood MTX, whole blood was precipitated with 50% trifluoroacetic acid, and extraction was performed using ethyl acetoacetate. Analytes were subjected to LC/MS/MS analysis using positive electrospray ionization. To determine whole-blood total MTX, whole blood was incubated with ascorbic acid (200 mM) at 37 °C for 3 h to enzymatically convert the MTXPGs to MTX, and then processed with the same method mentioned above. Recoveries of spiked MTX at ppb (ng/mL) level were between 26.2% and 37.8% with intra- and inter-day precision less than 15.8% and 11.8%, respectively. The lower limit of detection (LLOD) and lower limit of quantitation (LLOQ) were 0.5 ng/mL and 1 ng/mL, respectively. The sensitive LC/MS/MS method was fully validated with high selectivity and acceptable accuracy and precision, which was successfully applied to determine the erythrocyte methotrexate polyglutamates in patients with RA.
► An LC/MS/MS method was developed for determination of MTXPGs in erythrocyte.
► It's the first study using LC/MS/MS with liquid–liquid extraction to detect MTXPGs.
► The levels of MTXPGs are generated indirectly.
► The method is sensitive, simple, low cost and can be widely applied in many labs.
► The method has been applied to determine the concentration of MTX in patients with RA.
Journal: Journal of Chromatography B - Volume 907, 15 October 2012, Pages 41–48