QUANTIFICATION OF CYROMAZINE AND MELAMINE IN FISH AND POULTRY FEEDS BY HIGH PERFORMANCE LIQUID CHROMATOGRAPHY – DIODE ARRAY DETECTION

Abstract

This paper reports the quantities of cyromazine (CYR) and its metabolite melamine (MEL) used as additives in fish and poultry feed. The levels of triazine compounds in fish and poultry feed were determined using high-performance liquid chromatography coupled with diode-array detection (HPLC-DAD). Fish and poultry feed samples meant for various sizes of fishes and different types of chickens, respectively, were sampled. Samples were extracted using a solid-phase extraction (SPE) consisting of alkaline acetonitrile and phosphate buffer. The extracts were analysed using an Agilent HPLC and a Zorbax Eclipse plus C18 column. The detection and quantification limits (LOD and LOQ) were 1.29 – 1.48 and 3.94 – 4.50 µg/kg for MEL and CYR, respectively. The regression (r2 = 0.989), recovery (99.5 – 102.5%) and precision (RSD < 1) were excellent. Melamine concentration ranged between 85.2±14.3 and 520.0±90.3 µg/kg in fish feed, while CYR was 98.5±9.7 to 345.0±37.7 µg/kg in the samples. The chicken feed had 31.7±6.0 to 54.8±5.7 µg/kg MEL, and 117.6±24.8 to 257.6±16.6 µg/kg CYR. There was no significant difference in MEL concentration of fish feed (p>0.05), while there existed a difference a difference between MEL and CYR (p<0.05). There existed a significant difference between MEL concentrations in the poultry feed (p<0.05) and no difference between MEL and CYR. The two triazine compounds considered in this study were present at a lower concentration than the permissible level.