Abstract

SIMULTANEOUS DETERMINATION OF LYMECYCLINE AND TETRACYCLINE RESIDUES IN BOVINE MILK FOLLOWED BY MATRIX SOLID-PHASE DISPERSION COUPLED TO HIGHPERFORMANCE LIQUID CHROMATOGRAPHY WITH ULTRAVIOLET DETECTION

*Tentu. Nageswara Rao¹, T. Srinivasa Rao² and G. Silpa³

Abstract

A simple, sensitive and inexpensive method was developed using matrix solid-phase dispersion (MSPD), together with high performance liquid chromatographic method for determination of antibiotic residues (Lymecycline and Tetracycline) in bovine milk. The evaluated parameters included the type and amount of sorbent (silica gel, C18 and alumina) and the nature of eluent (20% trichloro acetic acid , 0.01M citric acid, 0.01M disodium hydrogen phosphate, 0.01M EDTA and Methanol). The best results were obtained using 2mL of milk sample, 1.0 g of C18 as sorbent and 20mL of 20% trichloroacetic acid , 0.01M citric acid, 0.01M disodium hydrogen phosphate, 0.01M EDTA and Methanol (1:2:2:2:3, (v/v)).The method was validated using in milk samples spiked with antibiotics at different concentration levels (0.01 and 0.1 μg/mL). Average recoveries (using each concentration six replicates) ranged 88-96%, with relative standard deviations less than 2%, calibration solutions concentration in the range 0.01-2.0 μg/mL and limit of detection (LOD) and limit of quantification (LOQ) were 0.01 μg/mL and 0.03 μg/mL respectively.

Keywords: matrix solid-phase dispersion, antibiotic residues, LOD and LOQ.