Home > EPH
Search results for: EPH
Error loading info... Pleas try again later.
#36692345 2023/01/24 To Up
Chiral Separation and Quantitation of Methylphenidate, Ethylphenidate and Ritalinic Acid in Blood using Supercritical Fluid Chromatography.Supercritical fluid chromatography is a technique that analyzes compounds that are temperature-labile, have moderately low weight, or chiral compounds. Methylphenidate (MPH) is a chiral compound with two chiral centers. MPH has two chiral metabolites, ethylphenidate (EPH) and ritalinic acid (RA). MPH is sold as a racemic mixture. The d- enantiomer of threo-MPH is responsible for medicinal effects. Due to the differing effects of the enantiomers, it is important to analyze the enantiomers individually to better understand their effects. This method utilizes SFC and solid-phase extraction (SPE) to separate and analyze the enantiomers of MPH, EPH and RA in postmortem blood. The objective of this method was to assess a unique approach with SFC for enantiomeric separation of MPH, EPH, and RA. A SPE method was developed and optimized to isolate the analytes in blood and validated as fit-for-purpose following international guidelines. The linear range for MPH and EPH was 0.25-25ng/mL and 10-1000ng/mL for RA in blood. Bias was -8.6 to 0.8% and precision was within 15.4% for all analytes. Following method validation, this technique was applied to the analysis of 49 authentic samples previously analyzed with an achiral method. Quantitative results for RA were comparable to achiral technique while there was loss of MPH and EPH over time. The l:d enantiomer ratio was calculated and MPH demonstrated greater abundance of the d enantiomer. This is the first known method to separate and quantify the enantiomers of all three analytes utilizing SFC and SPE.
Christina Smith, Svante Vikingsson, Robert Kronstrand, Madeleine J Swortwood