Development of an immunoassay for a quaternary ammonium compound, benzyldimethyldodecylammonium chloride

• Published in: Water research (Oxford) 1998-12, Vol.32 (12), p.3621-3630
• Main Authors: Bull, Jennifer P., Serreqi, Alessio N., Chen, Tao, Breuil, Colette
• Format: Article
• Language: English
• Subjects: ADBAC; BDD 12 AB; benzalkonium chloride; Biological and medical sciences; Biotechnology; ELISA; Fundamental and applied biological sciences. Psychology; immunoassay; Methods. Procedures. Technologies; Others; QAC; Various methods and equipments
• ISSN: 0043-1354; 1879-2448
• DOI: 10.1016/S0043-1354(98)00127-4

A competitive enzyme-linked immunosorbent assay (CELISA), based on polyclonal antibodies, was developed to measure benzyldimethyldodecylammonium chloride (BDD 12AC), a component of benzalkonium chloride (BAK). The polyclonal antibodies recognized free benzyldimethyldodecylammonium bromide (BDD 12AB) in an indirect competitive ELISA with a 50% inhibition (IC 50) of 0.66±0.20 μg/ml and a detection limit of 0.043±0.033 μg/ml. The two other components of BAK, benzyldimethyltetradecylammonium chloride (BDT 14AC) and benzyldimethylhexadecylammonium chloride (BDH 16AC), were recognized to varying degrees by the antibodies. The antibodies did not cross-react with other compounds such as fatty acids and alcohols, amino acids, amines, and short-chain quaternary ammonium compounds. Cross-reactivity was observed with other alkyldimethylbenzylammonium compounds (ADBACs). The CELISA and HPLC were used to measure the amount of pure BDD 12AB spikes in milk and BDD 12AC in five commercial products. HPLC analysis correlated well with CELISA analysis for spiked samples.