Development Of The Colloidal Gold Immunochromatographic Test Strip For The Detection Of Sulfonamides

Sulfonamides(SAs) are often used for the prevention and control of the animals’ diseases, which are widely used in clinic on animals, but long-time use may make accumulations in animals’ body, caused drug residues and potential hazard on human health. Currently, The detection of SAs residues in food derived are one of the important items in the food hygiene standard, mainly through the chromatography detection, but chromatography detection need complex operation. Therefore, establish a quick, simple method for the detection of SAs has important value.GICA has many advantages, such as convenient and quick, don’t need special equipment, result is clear, so it is suitable for preliminary screening of the sample, with widely application prospects. In this experiment, the strip for the detection of SAs was systematically studied, to development a fast way for detecting SAs residues by GICA.The trisodium citrate was used as reducing reagent to prepare colloidal gold, then the colloidal gold was labeled to the monoclonal antibody after identification. the combination was solidified to glass fibers, SAs-BSA and anti-mouse antibody was immobilised on nitrocellulose membrane to assemble the strip. Optimal conditions are: choose the colloidal gold of biggest absorption peak at 525 nm, combined pad selection: GL0194, mat sample selection:GL-b04, nitrocellulose membrane selection:SS24, dilution of antigen: 0.02 mol/L p H 8.0 PBS, the coating concentration of antigen was 0.05 mg/m L and anti-mouse antibody was 0.8mg/m L, dilution of gold labeled antibodies was 1:15.The limits of detection of SAs(SMD, SM1, SM2, SMM, SD, SDM, SMP, SPD) test strip was 10 μg/L, 10 μg/L, 10 μg/L, 10 μg/L, 20 μg/L, 20 μg/L, 20 μg/L, 20 μg/L, through testing, the strip showed good specificity, repeatability and stability.Pork, fish and milk samples were used as real sample which don’t contain SAs by LC-MS, add SAs to the three samples, through the samples pre-treatment, strip testing, the content of SAs beyond the MRL(100 μg/kg) can be checked out in three samples, pre-treatment method can be used, the strip for the detection of SAs residues has practical value.