Rapid preparation of expanded graphite by microwave irradiation for the extraction of triazine herbicides in milk samples

卷:197

Zhang, Fengshuang ; Zhao, Qi ; Yan, Xu ; Li, Huiyu ; Zhang, Ping ; Wang, Long ; Zhou, Tianyu ; Li, Yi ; Ding, Lan

Jilin Univ

关键词: Expanded graphite;    Microwave irradiation;    Triazine herbicides;    Milk samples;    Liquid chromatography-tandem mass spectrometry;    Solid-phase extraction;   

DOI  :  10.1016/j.foodchem.2015.11.056

学科分类：食品科学和技术

【 摘 要 】

In this study, we proposed a rapid and efficient method for the preparation of the expanded graphite (EG). The exfoliation process was accelerated by microwave irradiation, and the preparation time was greatly shortened. The obtained EG was worm-like in shape and exhibits well exfoliated structure. It was successfully applied as solid-phase extraction (SPE) adsorbent to extract and clean up the triazine herbicides in milk, followed by liquid chromatography tandem mass spectrometry (LC-MS) analysis. The parameters affecting the performance of extraction and LC-MS analysis were evaluated. Under the optimal conditions, the detection limits of triazines are in the range of 0.03-0.12 ng mL(-1). At the spiked level (0.4 ng mL(-1)), the recoveries of triazines are in the range of 82.5 +/- 2.5% to 97.5 +/- 7.5%. The proposed method was successfully applied to determine six triazines in six milk samples. (C) 2015 Elsevier Ltd. All rights reserved.