Department of Chemistry, Wuhan University, Wuhan 430072, China.
Talanta. 2011 Sep 30;85(4):2148-53. doi: 10.1016/j.talanta.2011.07.060. Epub 2011 Jul 22.
A novel method that combines two concentration techniques, off-line centrifuge microextraction (CME) and on-line sweeping, is used to determine trace steroids in urine by micellar electrokinetic chromatography (MEKC). The CME-sweeping-MEKC is a promising technique, which has a variety of merits such as high sensitivity, rapid operation, minimal cost, and high sample throughput capability. Using CME-sweeping, over a 500-fold increase in sensitivity could be obtained as compared with the normal hydrodynamic injection without sample stacking. The linear range was 0.05-1 μg mL(-1) with the square of the correlation coefficients ranging from 0.9998 to 0.9999. Detection limits (S/N=3) were 5-15 ng mL(-1) using a photodiode array UV detection at a wavelength of 240 nm. The relative standard deviations were between 2.8% and 3.5% (n=5, progesterone as the internal standard). The diode array UV spectrum used can distinguish the analytes from the interference in the complex sample matrix, which is useful in biological and clinical sample analysis.
一种将两种浓缩技术离线离心微萃取 (CME) 和在线扫集相结合的新方法用于通过胶束电动色谱 (MEKC) 测定尿液中的痕量甾体。CME-扫集-MEKC 是一种很有前途的技术，具有高灵敏度、快速操作、低成本和高样品通量能力等多种优点。与没有样品堆积的普通动力学进样相比，使用 CME 扫集可以获得 500 倍以上的灵敏度提高。线性范围为 0.05-1μg mL(-1)，相关系数的平方从 0.9998 到 0.9999。使用光电二极管阵列紫外检测在 240nm 波长下，检测限 (S/N=3) 为 5-15ng mL(-1)。相对标准偏差在 2.8%和 3.5%之间 (n=5，以孕激素为内标)。使用的二极管阵列紫外光谱可以将分析物与复杂样品基质中的干扰区分开来，这在生物和临床样品分析中很有用。
