Benzyldimethylhexadecylammonium chloride (Cetalkonium chloride) is an ammonium salt preservative that produces positive charges, making cationic nanoemulsions on the negatively charged ocular surface bioadhesive. Cetalkonium chloride can reduce inflammation and improve the healing of corneal lesions. Cetalkonium chloride can be used in studies of oral, throat and eye infections.