Estimation of Some Amino-Based Drugs in Human Blood Using HPLC Technique

Abstract

Enantiomers in human plasma were analyzed using Solid Phase Extraction (SPE) and Chiral High- Performance Liquid Chromatography (HPLC). The chiral HPLC strategy allowed fractionation of DL, DD, LL, and LD varieties in human blood plasma with Targeted Solid Phase Extraction (TSPE). These methods are precise, economical, eco-friendly, and reproducible. Maximum plasma binding percentages for DL-, DD-, LL-, and LD-enantiomers were 63.39%, 56.79%, 84.11%, and 73.11%, respectively, at pH 9. Chiral resolution was strong, with separation factors over 1.0. Limits of Detection (LOD) ranged from 1 to 2.7 μg/mL, and Limits of Quantitation (LOQ) ranged from 5 to 10 μg/mL. The experimental data aligned well with the model, successfully applied to real plasma samples, enabling chiral monitoring of dipeptide stereoisomers in patients. HPLC, using an AmyCoat-RP column with an amylose polysaccharide stationary phase, proved effective for consistent and robust analysis, confirming the suitability of D-tryptophan, L-leucine, D-leucine, and L-tryptophan stereoisomers for clinical and research applications.