Liu Xiaolan, Chen Beibei, Zhang Lin, Song Shiyao, Cai Yabing, He Man, Hu Bin
Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), Department of Chemistry, Wuhan University , Wuhan, Hubei 430072, China.
Anal Chem. 2015 Sep 1;87(17):8949-56. doi: 10.1021/acs.analchem.5b02111. Epub 2015 Aug 12.
In this work, a novel method of TiO2 nanoparticles (NPs) functionalized monolithic capillary microextraction (CME) online coupling with inductively coupled plasma mass spectrometry (ICPMS) was developed for the sequential determination of Gd(3+) and Gd-based contrast agents in human urine samples. The monolithic capillary was prepared by embedding anatase TiO2 NPS in the poly(methacrylic acid-ethylene glycol dimethacrylate) (MAA-EDMA) framework. The Gd(3+) and Gd-based contrast agents (such as gadolinium-diethylene triamine pentaacetic acid (Gd-DTPA) and Gd-DTPA-bismethylamide (Gd-DTPA-BMA)) display different adsorption behaviors on the prepared monolithic capillary which possesses the adsorption properties of both anatase TiO2 NPS and poly(MAA-EDMA) monolith. Under the optimized conditions, the limits of detection (LODs) were found to be 3.6, 3.2, and 4.5 ng L(-1) for Gd(3+), Gd-DTPA, and Gd-DTPA-BMA, respectively, which are the lowest up to date. The enrichment factor was 25-fold with the sample throughput of 5 h(-1). The proposed method was validated by the analysis of Gd(3+) and Gd-DTPA in the healthy human urine samples as well as Gd(3+) and Gd-DTPA-BMA in patient urine samples. It was found that only a small amount of the free Gd(3+) was released from Gd-DTPA-BMA, and accurate results could be obtained since no oxidation/reduction or subtraction is involved in this method. This method is simple, sensitive, and rapid and provides a very attractive nonchromatography strategy for the speciation of Gd(3+) and Gd-based contrast agents in urine samples.
在本研究中，开发了一种新型的二氧化钛纳米颗粒（NPs）功能化整体式毛细管微萃取（CME）与电感耦合等离子体质谱（ICPMS）在线联用的方法，用于顺序测定人尿液样本中的钆（Gd(3+)）和基于钆的造影剂。整体式毛细管是通过将锐钛矿型TiO2纳米颗粒嵌入聚（甲基丙烯酸-乙二醇二甲基丙烯酸酯）（MAA-EDMA）骨架中制备而成。Gd(3+)和基于钆的造影剂（如钆-二乙烯三胺五乙酸（Gd-DTPA）和钆-二乙烯三胺五乙酸双甲酰胺（Gd-DTPA-BMA））在制备的整体式毛细管上表现出不同的吸附行为，该毛细管同时具有锐钛矿型TiO2纳米颗粒和聚（MAA-EDMA）整体的吸附特性。在优化条件下，Gd(3+)、Gd-DTPA和Gd-DTPA-BMA的检测限（LOD）分别为3.6、3.2和4.5 ng L(-1)，是迄今为止最低的。富集因子为25倍，样品通量为5 h(-1)。通过分析健康人尿液样本中的Gd(3+)和Gd-DTPA以及患者尿液样本中的Gd(3+)和Gd-DTPA-BMA，对所提出的方法进行了验证。结果发现，Gd-DTPA-BMA仅释放出少量的游离Gd(3+)，且由于该方法不涉及氧化/还原或扣除操作，因此可以获得准确的结果。该方法简单、灵敏、快速，为尿液样本中Gd(3+)和基于钆的造影剂的形态分析提供了一种极具吸引力的非色谱策略。
