Benzalkonium chloride (BKC (also commonly BZK, BAK, BAC))

Benzalkonium chloride is a mixture of alkylbenzyldimethylammonium chlorides (quaternary ammonium salts) containing various even-numbered alkyl chain lengths, most commonly C12–C16, formulated as a colorless to yellow, viscous liquid or powder. It acts as a broad-spectrum antimicrobial agent by disrupting the lipid membranes of bacteria, fungi, and enveloped viruses, leading to cell death. Benzalkonium chloride is used as an active antiseptic and disinfectant agent in topical pharmaceuticals, multidose ophthalmic and nasal formulations, cleaning agents, hand sanitizers, and surface disinfectants. Its cationic surfactant properties also make it useful as a preservative and solubilizer, but its use can cause irritation and, rarely, sensitization. It is not a biological drug target (e.g., receptor, enzyme), but rather an antimicrobial chemical frequently used in healthcare and consumer products.

Other names

BenzalkoniumBenzalkonium chloridesAlkyldimethylbenzylammonium chloride (ADBAC)Alkylbenzyldimethylammonium chlorideBZKBKCBACBAKZephiran chlorideOsvanVarious trade names

Disrupts microorganism cell membrane integrity by integrating into and solubilizing lipid bilayers, leading to leakage of cellular contents and cell death - Acts as a cationic surfactant, interfering with microbial enzymes and metabolic pathways