ABSTRACT
Quaternary ammonium chlorides (QACs) occupy a unique niche in the world of antimicrobial compounds. Rather than being a single, well-defined substance, as is the case for many such active ingredients, QACs are composed of a diverse, eclectic collection of substances that share a common chemical motif, namely a molecular structure containing a positively charged nitrogen atom covalently bonded to four carbon atoms. This quaternary ammonium group is responsible for the name of these antimicrobial compounds and also plays a dominant role in determining their chemical behavior.
