Objective To establish an HPLC method for the simultaneousdetermination of 12 common bacteriostatic agents (benzoic acid, benzylalcohol, sorbic acid, methylparaben, thimerosal, ethylparaben,chlorhexidine acetate, propyl hydroxybenzoate, butyl p-hydroxybenzoate,benzalkonium bromide, domiphen bromide, benzalkonium chloride ) inbrimonidine tartrate eye drops. The 48 batches of samples collected from4 domestic manufacturers were tested and evaluated. Methods ShiseidoCAPCELL PAK C18 MGII column ( ${4.6}\mathrm{\;{mm}}\times {250}\mathrm{\;{mm}},{5\mu}\mathrm{m}$ ) was used, ${0.02}\mathrm{\;{mol}}/\mathrm{L}$ ammonium acetate(pH adjusted to 4.5 by glacial acetic acid)(mobile phaseA) and methyl alcohol(mobile phase B) were used for gradient elution,and the detection wavelength was ${262}\mathrm{\;{nm}}$ . Results Theseparation degree of 12 bacteriostatic agents reached the requirements,and the blank excipients did not interfere with the determination ofbacteriostatic agents, the linear relationship of bacteriostatic agentsin their linear range was good, the average recoveries were in the rangeof 92.8% to 105.7% and the RSDs were ${0.3}\%\sim {1.9}\%\left({\mathrm{n}=9}\right)$ . The qualitative analysis showed that the types ofbacterial inhibitors in 48 batches were all in agreement with theformulation. The quantitative determination showed that the contents ofbacterial inhibitors were between ${24}\%\sim {102}\%$ of the formulation. Conclusion The method is sensitive, rapid and specific, and can be usedfor the accurate quantitative determination of multiple bacteriostaticagents in brimonidine tartrate eye drops. This study can providetechnical support for the standardized use of bacteriostatic agents inthis variety.

bacteriostatic agents  /  brimonidine tartrate eye drops  /  gradient elution  /  high performance liquid chromatography