Fluorimetric determination of D- and L-lactate derivatized with 4-(N,N-dimethylaminosulfonyl)-7-piperazino-2,1,3-benzoxadiazole (DBD-PZ) by high-performance liquid chromatography

A highly sensitive method, based on fluorescence derivatization with 4-N, N -dimethylaminosulfonyl-7 -piperazino-2,1,3-benzoxadiazole (DBD-PZ), was dev eloped for the determination of D- and L-lactic acid. High-performance Liqu id chromatographic separation of the lactic acid derivative was achieved us ing an octadecylsilica column followed by enantiomeric separation on a phen ylcarbamoylated beta-cyclodextrin chiral column. The separation factor for D,L-lactic acid derivatives was 1.30 using MeOH/H2O (80/20) as a mobile pha se, and the detection limits were approximately 360 and 300 fmol on column for D- and L-lactic acid derivative, respectively. The proposed method was applied to determine D- and L-lactate in a wine and a lactic drink. Both D- and L-lactate could be determined simultaneously, with the precisions rang ing from 3.50 to 5.78% for intra-day and 4.28-9.92% for inter-day determina tions. The relative recovery was in the range of 91.6-100%. Copyright (C) 1 999 John Wiley & Sons, Ltd.