Development Of Colloidal Gold Lateral Flow Assay For Detection Of Melamine

Melamine is a kind of triazine azacyclo-compounds,. which is a chemical meterials using for woods, plastic, painting, and paper industry, etc. For high nitrogen content, it was added into the milk, feed, even the infant food. Some research indicated that the toxicity level of the melamine is low, but it may cause the genital system damage when people, especially the baby, has intaked the melamine for a long time. The damage would develop into the calculus in kidney or bladder, even the bladder cancer. In China, a few of melamine detect methods were set up recently, but they all need the expensive equipments, the complex pre-treatment and take a long time to analyse. It’s not fit for the rapid on-site detection. So a lateral flow assay was developed based on collidal gold. The method gets a high accuracy, sensitive and stability for melamine rapid on-site detection.The reaserch includes three parts as the follows:1) Preparation of melamine conjugation antigensIn the study, three structure modifyings had been prepared. After couplinged with bovine serum albumin(BSA), it was used as artificial antigen, after couplinged with ovalbumin as envelope antigen.2) Preparation of melamine monoclonal antibodiesIn the study, the monoclonal antibodies had been prepared by limiting dilution method, an cell strain named10G5-E9-A1had been obtained which can produce the anti-melamine monoclonal antibody. The monoclonal antibody was purified by octylic acid-saturated ammonium sulfate. The antibody had high specific to melamine.3) Preparation and valuation of the test tripIn the study, lateral flow assay of melamine based on colloidal gold was developed. The conjugate pad, sample pad, nitrocellulose membrane and wick of the test strip was selected, the condition was optimized. The results showed that the analysis time was10min, the LOD is10μg/L, and there was no false positive or false negative, the strip can be used for14months.