Study on the Diffusion-Dominated Solid-Phase Microextraction Kinetics in Semisolid Sample Matrix.
Study on the Diffusion-Dominated Solid-Phase Microextraction Kinetics in Semisolid Sample Matrix.
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半固体样品基质中扩散主导的固相微萃取动力学研究
DOI：
10.1021/acs.analchem.6b02673
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发表时间：
2016-08
影响因子：
7.4
通讯作者：
Ouyang Gangfeng
中科院分区：
文献类型：
--
作者：
Xu Jianqiao;Huang Shuyao;Wei Songbo;Yang Muzi;Cao Chenyang;Jiang Ruifen;Zhu Fang;Ouyang Gangfeng
固相微萃取(SPME)在半固体样品中的动力学与在水和气相样品中的不同，因为对流在半固体样品中可以忽略不计，但在水和气体样品中的传质起主导作用。本研究建立了描述半固态样品固相微萃取动力学的数学模型，该模型考虑了分析物在两个隔室中的扩散，即纤维涂层和样品基质中不断增加的扩散域。数学模型预测，在半固态样品中，固相微萃取和预装分析物从纤维上的解吸将是各向同性的，而半固态样品中的固相微萃取不符合水和气态样品的一级动力学。这些预测在琼脂糖凝胶中四种药物的实验中被证明是正确的。反过来，实验中观察到，对于纤维和样品基质之间分配系数较高的分析物，固相微萃取动力学将更明显地偏离一级动力学，这一点可以用本研究建立的数学模型很好地解释。此外，当扩散系数处于合理水平时，该模型预测的固相微萃取动力学与实验结果吻合较好，表明该模型能够较好地描述半固态样品的固相微萃取动力学。半固体样品的非一阶固相微萃取动力学的图解对于评价现有的半固体样品的预平衡校正方法的适用性具有重要的参考价值。
Solid-phase microextraction (SPME) kinetics in semisolid samples should be different from that in aqueous and gaseous samples, as convection is negligible in semisolid samples but dominates mass transfer in bulk phases of aqueous and gaseous samples. This study developed a mathematical model for describing SPME kinetics in semisolid samples by considering the diffusion of analytes in two compartments, i.e., the fiber coating and the ever-increasing diffusion domain in the sample matrix. The mathematical model predicted that SPME and the desorption of preloaded analytes from the fiber would be isotropic in semisolid samples, while SPME in semisolid samples would not follow the first order kinetics as in aqueous and gaseous samples. The predictions were proven true in the experiment of four pharmaceuticals in agarose gel. In return, it was observed in the experiment that SPME kinetics would deviate more significantly from the first order kinetics for the analytes with higher partition coefficients between the fiber and the sample matrix, which was well explained by the mathematical model developed in this study. In addition, SPME kinetics predicted by the model coincided well with the experimental results when the diffusion coefficients were at reasonable levels, which demonstrated that the model could be satisfactory for describing SPME kinetics in semisolid samples. The illustration of the nonfirst order SPME kinetics in semisolid samples can be valuable for evaluating the applicability of the existing pre-equilibrium calibration methods in semisolid samples.
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影响因子：
7.4
作者：
Ai, J
通讯作者：
Ai, J
影响因子：
16.6
作者：
Cudjoe, Erasmus;Bojko, Barbara;Pawliszyn, Janusz
通讯作者：
Pawliszyn, Janusz
影响因子：
7.4
作者：
S. Zhou;Wennan Zhao;J. Pawliszyn
通讯作者：
S. Zhou;Wennan Zhao;J. Pawliszyn
影响因子：
11.4
作者：
Jianqiao Xu;Junpeng Luo;Jingwen Ruan;Fang Zhu;Tiangang Luan;H. Liu;Ruifen Jiang;Gangfeng Ouyang-Gangfeng
通讯作者：
Jianqiao Xu;Junpeng Luo;Jingwen Ruan;Fang Zhu;Tiangang Luan;H. Liu;Ruifen Jiang;Gangfeng Ouyang-Gangfeng
影响因子：
3.7
作者：
Klose, D.;Azaroual, N.;Siepmann, J.
通讯作者：
Siepmann, J.