Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), Department of Chemistry, Wuhan University, Wuhan 430072, PR China.
Talanta. 2012 May 30;94:278-83. doi: 10.1016/j.talanta.2012.03.040. Epub 2012 Mar 28.
We report here the preparation of high-magnetization Fe(3)O(4)@SiO(2)@TiO(2) nanoparticles for solid phase extraction of trace amounts of Cd(II), Cr(III), Mn(II) and Cu(II) from environmental waters. The prepared nanoparticles were characterized by scanning electron micrograph (SEM) and transmission electron microscopy (TEM). The high-magnetization nanoparticles carrying the target metals could be easily and fast separated from the aqueous solution simply by applying an external magnetic field while no filtration or centrifugation was necessary. A light-induced hydroxide ion emitter, molecular malachite green carbinol base (MGCB) was applied to adjust pH value of solution for quantitative adsorption instead of the conventional used buffer. In the presence of UV light, MGCB gives out OH(-) ions, and this leads to an increase in the pH value without the aid of buffer solution. Using high-magnetization Fe(3)O(4)@SiO(2)@TiO(2) nanoparticles as the extraction material and the light-induced MGCB for pH adjustment, we developed an efficient and convenient two-step method for separation/preconcentration trace amounts of Cd(II), Cr(III), Mn(II) and Cu(II) in environmental water samples followed by inductively coupled plasma mass spectrometry (ICP-MS) detection. The parameters affecting the extraction such as MGCB concentration, exposal time, sample volume, eluent condition, and interfering ions have been investigated in detail. Under the optimized conditions, the limits of detection for Cd(II), Cr(III), Mn(II) and Cu(II) were 4.0, 2.6, 1.6 and 2.3 ng L(-1), respectively, and the relative standard deviations (RSDs, c=1 μg L(-1), n=7) were 3.6%, 4.5%, 4.0 and 4.1%, respectively. The proposed method has been validated using certified reference materials, and it has been successfully applied in the determination of trace Cd(II), Cr(III), Mn(II) and Cu(II) in environmental water samples.
我们在此报告了高磁化率 Fe(3)O(4)@SiO(2)@TiO(2)纳米粒子的制备，用于从环境水中固相萃取痕量的 Cd(II)、Cr(III)、Mn(II)和 Cu(II)。所制备的纳米粒子通过扫描电子显微镜 (SEM) 和透射电子显微镜 (TEM) 进行了表征。带有目标金属的高磁化率纳米粒子可以通过施加外部磁场轻松快速地从水溶液中分离出来，而无需过滤或离心。一种光致氢氧根离子发射器，分子孔雀石绿甲醇基 (MGCB) 被应用于调整溶液的 pH 值以进行定量吸附，而不是传统使用的缓冲液。在紫外光的存在下，MGCB 释放出 OH(-)离子，这导致 pH 值升高，而无需缓冲溶液的帮助。我们使用高磁化率 Fe(3)O(4)@SiO(2)@TiO(2)纳米粒子作为萃取材料，以及光致 MGCB 用于 pH 调节，开发了一种高效、便捷的两步法，用于分离/预浓缩环境水样中的痕量 Cd(II)、Cr(III)、Mn(II)和 Cu(II)，然后进行电感耦合等离子体质谱 (ICP-MS) 检测。详细研究了影响萃取的参数，如 MGCB 浓度、暴露时间、样品体积、洗脱条件和干扰离子。在优化条件下，Cd(II)、Cr(III)、Mn(II)和 Cu(II)的检出限分别为 4.0、2.6、1.6 和 2.3 ng L(-1)，相对标准偏差 (RSDs，c=1 μg L(-1)，n=7) 分别为 3.6%、4.5%、4.0%和 4.1%。该方法已通过认证参考材料进行验证，并已成功应用于环境水样中痕量 Cd(II)、Cr(III)、Mn(II)和 Cu(II)的测定。
