Generation of antibody and development of an enzyme-linked immunosorbant assay for the feed additive roxarsone

Roxarsone is used in the poultry and swine industries as a feed additive to treat coccidiosis and other intestinal disorders as well as to improve feed efficiencies and weight gain. 3-Amino-4-hydroxyphenylarsonic acid (AHPA) was conjugated with keyhole limpet hemocyanin in the presence of bis-sulfosuccinimidyl-suberate for the immunogen in rabbits. The antibody has minor cross-reactivity towards 2-aminophenylarsonic acid (7.3%, n = 3), arsanilic acid (5.3%, n = 3), AHPA (4%, n = 3), and phenylarsonic acid (3%, n = 3). The mean IC(50)s for PBST, muscle 1:10, and muscle 1:20 were 11.7 +/- 1.50, 13.1 +/- 2.53 and 12.0 +/- 2.45 ng/mL (n = 6). Using a standard curve prepared in chicken muscle extract and diluted with PBST at 1:20, muscle samples spiked with roxarsone at 2.5, 5, 10 and 25 ng/mL had recoveries of 117%, 98%, 80% and 65% having coefficients of variation of 36, 9.2, 10.2 and 11.5 respectively (n = 6).