Silva Ana Rita M, Nogueira J M F
University of Lisbon, Faculty of Sciences, Chemistry and Biochemistry Department, Campo Grande Ed. C8, 1749-016 Lisbon, Portugal.
Talanta. 2008 Feb 15;74(5):1498-504. doi: 10.1016/j.talanta.2007.09.040. Epub 2007 Oct 13.
Stir bar sorptive extraction and liquid desorption followed by high performance liquid chromatography with diode array detection (SBSE-LD-LC-DAD) is proposed for the determination of triclosan in personal care products, biological and environmental matrices, which is included in the priority lists, set by several international regulatory organizations. Instrumental conditions and experimental parameters that affecting SBSE-LD efficiency are fully discussed. Throughout systematic assays on 25 mL water samples spiked at the 10.0 microg L(-1) level, it had been established that stir bars coated with 126 microL of polydimethylsiloxane, an equilibrium time of 1h (1000 rpm) and acetonitrile under sonification (60 min) as back-extraction solvent, allowed the best analytical performance to determine triclosan in water matrices. From the data obtained, good recovery and remarkable repeatability were attained, providing experimental average yields (78.5+/-2.2%), although slightly lower than the theoretical equilibrium (99.7%) described by the octanol-water partition coefficients (K(PDMS/W)<K(O/W)). The analytical performance proved suitable precision (<3.6%), convenient detection limits (0.1 microg L(-1)) and excellent linear dynamic range (r(2)>0.9992) from 0.4 to 108.0 microg L(-1). The application of the present method to determine triclosan in real matrices such as commercial toothpaste, saliva and urban wastewater samples, allowed appropriate selectivity, high sensitivity and accuracy using the standard addition methodology. The proposed method showed to be feasible and sensitive with a low-sample volume requirement to monitor triclosan in personal care products, biological and environmental matrices at the trace level, in compliance with international regulatory directives.
本文提出了一种搅拌棒吸附萃取-液体解吸-高效液相色谱-二极管阵列检测法(SBSE-LD-LC-DAD),用于测定个人护理产品、生物和环境基质中的三氯生。三氯生被多个国际监管组织列入优先监测清单。文中充分讨论了影响SBSE-LD效率的仪器条件和实验参数。通过对加标浓度为10.0 μg L⁻¹的25 mL水样进行系统分析,确定涂覆126 μL聚二甲基硅氧烷的搅拌棒、1 h(1000 rpm)的平衡时间以及超声处理(60 min)下的乙腈作为反萃取溶剂,能够在水基质中实现对三氯生的最佳分析性能。根据所得数据,回收率良好且重复性显著,实验平均回收率为(78.5±2.2%),尽管略低于由正辛醇-水分配系数描述的理论平衡值(99.7%)(K(PDMS/W)<K(O/W))。该分析方法具有合适的精密度(<3.6%)、便捷的检测限(0.1 μg L⁻¹)以及0.4至108.0 μg L⁻¹范围内出色的线性动态范围(r²>0.9992)。将本方法应用于商业牙膏、唾液和城市废水等实际基质中三氯生的测定,采用标准加入法可实现适当的选择性、高灵敏度和准确性。所提出的方法可行且灵敏,对样品体积要求低,能够在痕量水平监测个人护理产品、生物和环境基质中的三氯生,符合国际监管指令要求。