建立了高效液相色谱法同时测定漱口水中5种抑菌成分（氯己定、西吡氯铵、尼泊金乙酯、对羟基苯甲酸甲酯钠、度米芬）含量的方法，采用乙腈-0.05 mol/L磷酸盐缓冲液（pH 3.8）（体积比20∶80）提取，超声参数为功率300 W、提取时间20 min、温度40 ℃、料液比1∶4。采用Agilent 1260高效液相色谱仪（配备二极管阵列检测器），色谱柱为Agilent ZORBAX Eclipse Plus C18反相色谱柱（250 mm×4.6 mm, 5 μm），柱温30 ℃，进样量10 μL，流速1.0 mL/min，检测波长260 nm，运行时间30 min。方法学评价显示，日内精密度中，5种成分相对标准偏差（RSD）为2.33%~4.72%；日间精密度RSD为1.01%~4.21%。线性回归分析显示，5种成分相关系数（
r）均>0.999 5，检出限（LOD）为0.09~0.18 μg/mL，定量限（LOQ）为0.27~0.54 μg/mL。加标回收实验显示，5种成分平均回收率为96.02%~104.65%，RSD为1.74%~4.53%。市售20种漱口水检测显示：氯己定仅S15、S19检出（1.25和1.27 mg/mL），西吡氯铵在7款样品中检出（0.13~0.75 mg/mL），尼泊金乙酯仅S4检出（0.15 mg/mL），对羟基苯甲酸甲酯钠仅S18检出（1.19 mg/mL），度米芬仅S20检出（0.32 mg/mL），其余9款样品未检出。本方法可对市售漱口水中5种抑菌成分实现同步、快速检测。
This study developed a high-performance liquid chromatography （HPLC） method for the simultaneous determination of five antibacterial components （chlorhexidine, cetylpyridinium chloride, ethylparaben, sodium methylparaben, and domiphen bromide） in mouthwash. Mouthwash samples were extracted using acetonitrile-0.05 mol/L phosphate buffer （pH 3.8） at a volume ratio of 20∶80. Ultrasonic extraction parameters were set as follows: power of 300 W, extraction time of 20 minutes, temperature of 40 ℃, and solid-to-liquid ratio of 1∶4. An Agilent 1260 HPLC system, equipped with a diode array detector （DAD）, was employed using an Agilent ZORBAX Eclipse Plus C18 reversed-phase column （250 mm×4.6 mm, 5 μm）. The column temperature was maintained at 30 ℃, with an injection volume of 10 μL, flow rate of 1.0 mL/min, detection wavelength of 260 nm, and total run time of 30 minutes. Methodological validation demonstrates that for intraday precision, the relative standard deviations （RSDs） of the five components range from 2.33% to 4.72%, while interday precision RSDs range from 1.01% to 4.21%. Linear regression analysis reveals that all five components exhibit excellent linearity with the correlation coefficients （r）>0.999 5, the limits of detection （LOD） ranging from 0.09 to 0.18 μg/mL and the limits of quantification （LOQ） ranging from 0.27 to 0.54 μg/mL. Spike recovery experiments indicate that the average recovery rates of the five components range from 96.02% to 104.65%, with the corresponding RSDs of 1.74% to 4.53%. Detection of 20 commercial mouthwash samples show that chlorhexidine is detected only in samples S15 and S19 at the concentrations of 1.25 and 1.27 mg/mL, respectively. Cetylpyridinium chloride is detected in 7 samples with the concentrations ranging from 0.13 to 0.75 mg/mL. Ethylparaben is detected solely in sample S4 at 0.15 mg/mL. Sodium methylparaben is found only in sample S18 at 1.19 mg/mL. Domiphen bromide is detected exclusively in sample S20 at 0.32 mg/mL, and the remaining 9 samples show no detection of the target components. In conclusion, this method enables simultaneous and rapid detection of the five target antibacterial components in commercial mouthwashes.
