3Kovacs-Hadady K, Fabian I. The determination of benzalkonium chloride in eye-drops by difference spectrophotometry [J]. JPharm BiomedAnal, 1998, 16 (5): 733-740.
4Fan TY, Wall GM. Determination of benzalkonium chloride in ophthalmic solutions containing tyloxapol by solid-phase extraction and reversed-phase high-performance liquid chromatography [J]. J Pharm Sci, 1993, 82 (11) : 1172-1174.
5Hou YH, Wu CY, Ding WH. Development and validation of a capillary zone electrophoresis method for the determination of benzalkonium chlorides in ophthalmic solutions [J]. J ChromatogrA, 2002, 976 (1-2): 207-213.
6Labranche LP, Dumont SN, Levesque S, et al. Rapid determination of total benzalkonium chloride content in ophthalmic formulation [J]. J Pharm Biomed Anal, 2007, 43 (3) : 989-993.