Departamento de Química Analítica, Nutrición y Bromatología, Universidad de La Laguna, 38206 La Laguna, Tenerife, Spain.
Talanta. 2010 Mar 15;80(5):1611-8. doi: 10.1016/j.talanta.2009.09.057. Epub 2009 Oct 4.
Two liquid-phase microextraction procedures: single-drop microextraction (SDME) and dispersive liquid-liquid microextraction (DLLME), have been developed for the determination of several endocrine-disrupting phenols (EDPs) in seawaters, in combination with high-performance liquid chromatography (HPLC) with UV detection. The EDPs studied were bisphenol-A, 4-cumylphenol, 4-tertbutylphenol, 4-octylphenol and 4-n-nonylphenol. The optimized SDME method used 2.5 microL of decanol suspended at the tip of a micro-syringe immersed in 5 mL of seawater sample, and 60 min for the extraction time. The performance of the SDME is characterized for average relative recoveries of 102+/-11%, precision values (RSD)<9.4% (spiked level of 50 ng mL(-1)), and detection limits between 4 and 9 ng mL(-1). The optimized DLLME method used 150 microL of a mixture acetonitrile:decanol (ratio 15.7, v/v), which is quickly added to 5 mL of seawater sample, then subjected to vortex during 4 min and centrifuged at 2000 rpm for another 5 min. The performance of the DLLME is characterized for average relative recoveries of 98.7+/-3.7%, precision values (RSD)<7.2% (spiked level of 20 ng mL(-1)), and detection limits between 0.2 and 1.6 ng mL(-1). The efficiencies of both methods have also been compared with spiked real seawater samples. The DLLME method has shown to be a more efficient approach for the determination of EDPs in seawater matrices, presenting enrichment factors ranging from 123 to 275, average relative recoveries of 110+/-11%, and precision values (RSD)<14%, when using a real seawaters (spiked level of 3.5 ng mL(-1)).
单滴微萃取（SDME）和分散液相微萃取（DLLME）已被开发用于海水中几种内分泌干扰酚（EDP）的测定，与高效液相色谱（HPLC）结合使用，采用紫外检测。所研究的 EDP 包括双酚 A、4-枯基酚、4-叔丁基酚、4-辛基酚和 4-壬基酚。优化的 SDME 方法使用 2.5 μL 癸醇悬停在微注射器尖端，浸入 5 mL 海水样品中，并在萃取时间为 60 min。SDME 的性能特点是平均相对回收率为 102+/-11%，精密度值（RSD）<9.4%（50 ng mL（-1）的加标水平），检测限为 4-9 ng mL（-1）。优化的 DLLME 方法使用 150 μL 乙腈：癸醇混合物（体积比 15.7，v/v），迅速加入 5 mL 海水样品中，然后在涡旋 4 min，在 2000 rpm 下离心 5 min。DLLME 的性能特点是平均相对回收率为 98.7+/-3.7%，精密度值（RSD）<7.2%（20 ng mL（-1）的加标水平），检测限为 0.2-1.6 ng mL（-1）。还比较了两种方法对加标实际海水样品的效率。在使用实际海水（加标水平为 3.5 ng mL（-1））时，DLLME 方法显示出对海水中 EDP 测定更有效的方法，其富集因子范围为 123-275，平均相对回收率为 110+/-11%，精密度值（RSD）<14%。
