Abstract
A direct enantioselective high-performance liquid chromatography (HPLC) method was employed successfully for determination of the enantiomeric purity of L-arginine. The elaborated method used teicoplanin macrocyclic antibiotic chiral stationary phase (CSP), known as Chirobiotic T, with a reversed-phase mobile phase consisting of methanol:50 mM sodium dihydrogen phosphate buffer, pH 4.6 (2:8, v/v), at a flow rate of 1.0 mL/min and UV detection at 214 nm. Linearity, precision, accuracy, and the quantitation limit were determined. The method proved to be capable of determining 0.0025% (w/w) of D-arginine (the enantiomeric impurity) contrary to the pharmacopoeial limit measurement, in which only amounts of D-arginine higher than 1.5% (w/w) caused the measurement to fail.