Simultaneous Determination of FOur Arsenic Additives in Animal Feed by Capillary Electrophoresis

摘要

Four additives,[4-hydroxy-3-nitrophenylarsonic acid(Roxarsone),4-nitrophenylarsonic acid(4-NPAA),phenylarsonic acid (PAA) and p-aminophenylarsonic acid (p-ASA)] in chicken feed were simultaneously determinated by capillary zone electrophoresis(CZE) with on -line UV-detection.Based on our previous research,the sample extraction,cleanup and detection condition were discussed and optimised,Analytes were extracted with acidic 20% acetonitrile and the cleaned up with C18 SPE before the detection.20mM Carbonate buffer at pH10 was used as electrolyte,A fused silica capillary(48.5cm x75um),18kV working voltage and 200nm detection wavelength were applied for CE detection.Acetonitrile functioned as a modifier to reduce the conductivity of the sample soulution during the CE separation.The sensityvity of the method is sufficient for the routine inspection of Roxarsone in animal feed,The recoveries for all analytes were reasonably good but the precision of the method was poorer than HPLC.