非水毛细管电泳法同时测定消毒剂、个人护理品及药膏中三氯生、三氯卡班和对氯间二甲苯酚

Simultaneous determination of triclosan,triclocarban and p-chloro-m-xylenol in disinfectant,personal care products and oiltment by nonaqueous capillary electrophoresis

三氯生(TCS)、三氯卡班(TCC)和对氯间二甲苯酚(PCMX)这3种消毒有效成分因广谱杀菌而广泛应用于消毒剂、个人护理品及药品中。为监督这些产品质量、保障消毒效果,非常有必要建立同时分析这3种消毒有效成分的方法。鉴于此,该文以十二烷基三甲基溴化铵(DTAB)为电渗流反转剂,建立了同时测定上述3种消毒有效成分的非水毛细管电泳-紫外检测新方法,并对分离缓冲体系及浓度、样品介质等条件进行了优化。结果表明,未涂层熔融石英毛细管(20.0 cm×50.0μm,总长度30.2 cm)为分离毛细管,14 mmol/L硼砂、2 g/L聚乙二醇20000和0.5 mmol/L DTAB的甲醇溶液为分离缓冲溶液,样品介质为含5 g/L聚乙二醇20000的甲醇-乙腈(50∶50,v/v),在214 nm下进行检测,实现了3种消毒有效成分的同时分离。在1~100 mg/L范围内,3种消毒有效成分的校正峰面积与质量浓度呈良好的线性关系,相关系数(r)均大于0.99。方法的检出限(LOD,信噪比为3)为0.2 mg/L,定量限(LOQ,信噪比为10)为1.0 mg/L;加标回收率在94.5%~104.4%范围内,相对标准偏差均小于4.8%。利用研究建立的新方法测定了消毒液、洗手液、婴儿爽身粉、抑菌乳膏共31件样品,并将结果与国家标准方法GB/T 27947-2020和GB/T 34856-2017中的液相色谱法结果相比较,无统计学显著性差异。与国标方法相比,方法极大地减少了有机溶剂消耗量。该法前处理简单,结果准确,非常适合实验室的常规分析。

Triclosan(TCS),triclocarban(TCC),and p-chloro-m-xylenol(PCMX)are some of the most widely used antibiotics because of their broad-spectrum and highly-efficient bactericidal effects.In the context of disinfection,the National Standard GB 38598-2020 stipulates that the contents of the effective ingredients present in a disinfectant must be specified,wherein their range must fall within 90%-110%of the specified central value.To ensure a suitable product quality,analysis by high performance liquid chromatography(HPLC)is recommended by both the GB/T 27947-2020 and GB/T 34856-2017.However,the results analyzed according to the National Standard method often exceed the declared contents,thereby indicating the necessity to establish a new method based on a completely different principle(e.g.,capillary electrophoresis),especially since it was not possible to analyze TCS,TCC,and PCMX in a single injection using the National Standard method.Moreover,using this method,large amounts of methanol were consumed,which could be potentially harmful to both operators and the environment.In terms of their water solubilities,this decreases in the order of PCMX>TCS>TCC,wherein TCC is insoluble in water.As such,the use of nonaqueous capillary electrophoresis(NACE)based on running buffer solutions prepared in pure organic solvents(e.g.,methanol or acetonitrile)is necessary.In this paper,a new NACE approach combined with an ultraviolet detection method was developed for the simultaneous analysis of TCS,TCC,and PCMX in disinfectants,personal care products,and ointments.For this purpose,an uncoated fused silica capillary(20 cm×50μm,total length=30.2 cm)was used as the separation column with a separation buffer composed of 14 mmol/L sodium borate,2 g/L polyethylene glycol(PEG)20000,and 0.5 mmol/L dodecyltrimethylammonium bromide(DTAB)in methanol.Following optimization of the separation parameters,the complete and simultaneous separation of TCS,TCC,and PCMX was achieved when the sample solution was prepared using 5 g/L PEG 20000 in methanol-acetonitrile(50∶50,v/v).It was possible to directly inject the sample into the analysis system after a simple dilution with the sample medium,and no interference was observed in any of the sample electropherograms when a separation voltage and detection wavelength of-12 kV and 214 nm were employed,respectively.Furthermore,TCS,TCC,and PCMX showed good linear relationships with their corrected peak areas within a mass concentration range of 1-100 mg/L,and the correlation coefficients(r)were all greater than 0.99.Moreover,the limits of detection(LODs,S/N=3)and limits of quantification(LOQs,S/N=10)were determined to be 0.2 and 1 mg/L,respectively.The spiked recoveries ranged from 94.5%to 104.4%with relative standard deviations of≤4.8%in all cases.Subsequently,the established method was used to analyze 31 commercial samples,including hand sanitizer,disinfectant,baby powder,and antibacterial cream.A comparative analysis of HPLC,the developed NACE method,and our previously reported micellar electrokinetic chromatographic(MEKC)method was also carried out for the quantitative determination of TCS,TCC,and PCMX.Although no statistically significant differences were observed among the three methods,the results determined for 16 out of the 31 samples did not match the claimed contents.These results therefore indicate the necessity to further control the compositions of disinfectant products.Our results indicate that the newly established NACE method can be an important alternative to HPLC for routine laboratory analyses,especially considering that it minimizes waste generation,requires only a simple sample pretreatment process,and exhibits a good selectivity to the target compounds.It is therefore hoped that the NACE method will be incorporated into the National Standard method in the near future.