建立了高效液相色谱法（HPLC）同时测定季铵盐复合消毒液样品中苯扎溴铵和邻苯二甲醛（OPA）含量的方法。用流动相[体积比为1∶1的0.02 mol·L^-1的乙酸-乙酸铵缓冲溶液（pH 4.5）和甲醇混合而成]将1.0 mL样品定容至10.0 mL，涡旋混合5 min后过0.45 μm滤膜，取滤液供HPLC分析。以XDB-C₁₈色谱柱为固定相，用流动相进行等度洗脱分离，在检测波长263 nm处测定目标物。结果表明，苯扎溴铵和OPA标准曲线的线性范围均为10.0~800.0 mg·L^-1，方法检出限（3S/N）分别为5.0，3.5 mg·L^-1。以此方法分析了3个样品，所得结果和标示值一致，测定值的相对标准偏差（n=7）均小于1.0%。以这3个样品为基质进行3个浓度水平的加标回收试验，得到苯扎溴铵和OPA的回收率分别为93.7%~95.2%和94.5%~98.5%。

A HPLC method for simultaneous determination of benzalkonium bromide and o-phthalaldehyde (OPA) in quaternary ammonium compound salt disinfectant was established. 1.0 mL of the sample was made up to 10.0 mL with the mobile phase[mixture composed of 0.02 mol·L^-1 acetic acid-ammonium acetate buffer solution (pH 4.5) and methanol in the volume ratio of 1:1] as dilution solvent. After mixing for 5 minutes by votex, the sample solution was passed through a 0.45 μm filter membrane, and the 2 analytes in the filtrate were determined by HPLC at the detection wavelength of 263 nm under conditions using XDB-C₁₈ column as stationary phase and isocratic elution with mobile phase. As found by results that linearity range of standard curves of benzalkonium bromide and OPA was found same in the range of 10.0-800.0 mg·L^-1, and detection limits of benzalkonium bromide and OPA were 5.0, 3.5 mg·L^-1, respectively. The 3 sample were analyzed by the above method, and results obtained were in conformity with the label values, with RSDs (n=7) of determined values lower than 1.0%. Recovery test was made by standard addition method using the 3 samples as matrixes at the 3 concentration levels, giving values of recovery of 93.7%-95.2% and 94.5%-98.5%, respectively.