多壁碳纳米管分散固相萃取净化在测定水产品中3种微囊藻毒素的应用及与固相萃取法的比较

建立多壁碳纳米管净化-超高效液相色谱-串联质谱法对水产品中3种微囊藻毒素残留量的测定方法。水产品用80%甲醇溶液提取,经多壁碳纳米管净化后,采用电喷雾正离子多反应监测模式进行分析。对不同性质碳纳米管进行考察,并对净化条件进行优化。将优化后的分散固相萃取条件与采用HLB柱固相萃取的净化方式进行比较,两者在1~50 μg/L范围内呈现良好的线性,线性相关系数均大于0.99,3种微囊藻毒素的检出限为0.1~0.2 μg/kg。在不同浓度水平下进行加标实验,平均回收率在88.7%~95.5%之间,相对标准偏差不大于4.2%。该方法适用于水产品中微囊藻毒素的痕量检测。

Application of Multi-Walled Carbon Nanotubes as a Sorbent in Dispersive Solid Phase Extraction and Comparison with Solid Phase Extraction for the Determination of Three Microcystins in Aquatic Products

An ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed for the determination of 3 microcystins (MCs) in aquatic products. The samples were extracted with methanol-water (8:2, V/V) and the extract was then cleaned up by multi-walled carbon nanotubes (MWCNTs). The target analytes were detected by UPLC-MS/MS using positive electrospray ionization (ESI+) in the multiple reaction monitoring (MRM) mode. Different MWCNTs were investigated for their suitability as sorbents for dispersive solid phase extraction (DSPE) and the purification conditions were optimized. The efficiency of the optimized DSPE conditions was compared to that of solid phase extraction using HLB column. Both purification methods showed a good linearity (R2 ≥ 0.99) over the concentration range from 1 to 50 μg/L and their limits of quantification were in the range of 0.1–0.2 μg/kg. The average recoveries of three MCs at different spiked levels were 88.7%–95.5% with relative standard deviations (RSDs) equal to or lower than 4.2%. This DSPE method can be suitable for the rapid detection of trace microcystins in aquatic products.