An immunoassay for benzyldimethyldodecylammonium chloride, a multipurpose disinfectant and fungicide
J Bull, A N Serreqi, Tao Chen, C Breuil
A competitive enzyme-linked immunosorbent assay (ELISA), based on polyclonal antibodies, was developed to measure benzyldimethyldodecylammonium chloride (BDDAC). The anti-BDDAC polyclonal antibodies recognized free BDDAC in an indirect competitive ELISA. The detection limit. based on the 20% inhibition (IC20), was 0.18 µg/ml and the 50% inhibition (IC50) was 1.1 µg/ml. The antibodies recognised the whole molecule and cross-reacted minimally with other compounds such as long-chain (C8 to C 12) fatty acids and alcohols, amino acids, amines, quaternary ammonium compounds and benzylated compounds. The competitive ELISA was used to measure the amount of BDDAC present in a commercial Lysol® disinfectant and two available antisapstain products. Diffusit QB and Hydrokoat 4. Assay development also included assay optimisation, false positive and false negative tests, and studying matrix effects using a western hemlock wood leachate.