School of Biology and Biological Engineering, South China University of Technology, Guangzhou, 510006, China.
Shimadzu (China) Corporation, Guangzhou Branch, 510010, China.
Anal Chim Acta. 2020 Mar 8;1101:184-192. doi: 10.1016/j.aca.2019.12.011. Epub 2019 Dec 7.
An automatic online solid-phase dehydrate extraction (SPDE)-ultra-high performance supercritical fluid chromatography (UHPSFC)-MS/MS system was developed in this study, in which the automatic SPDE procedure was coupled with UHPSFC to allow UHPSFC to analyze aqueous samples directly. Moreover, a pre-column dilution strategy was employed, which focused the analytes in strong desorption solvent on the column head and helped to obtain narrow and symmetric peaks. The online SPDE-UHPSFC-MS/MS system was firstly applied to the screening of 45 prohibited substances in human urine for doping control, during which all the mechanisms and features of the online system were fully studied. The majority (91%) of the target compounds achieved weak matrix effects (80-120%), indicating that the online method was accurate and reliable thanks to the SPDE procedure and efficient UHPSFC separation. Owing to the reduction of the matrix effects, large volume injection and the pre-column dilution, the online system could achieve high sensitivity with the LODs ranging from 0.0380 ng L to 1.24 μg L. Under the optimized conditions, the extraction recoveries of 66% target analytes were more than 50%. All the target compounds showed good linearity with linear correlation coefficients higher than 0.9928. The accuracy values of all the spiked prohibited substances were within 80.8-119.7%, while the RSDs% for the intra-/inter-day precision were within 10.8% and 15.4%. Compared with the dilute-and-shoot-ultra-high performance liquid chromatography-MS/MS method, in which the urine samples were simply diluted before analyzing, this online method was superior in sensitivity and reducing matrix effects, which demonstrated its utility in doping control. Compared with the previously reported online SPE-SFC system, the online SPDE-UHPSFC-MS/MS system showed advantages in automation, efficiency, sensitivity and chromatographic performance. In summary, the online SPDE-UHPSFC-MS/MS system is capable of analyzing complex aqueous samples.
本研究建立了一种自动在线固相脱水萃取（SPDE）-超高效超临界流体色谱（UHPSFC）-MS/MS 系统，该系统将自动 SPDE 程序与 UHPSFC 耦合，使 UHPSFC 能够直接分析水性样品。此外，还采用了柱前稀释策略，将分析物聚焦在强洗脱溶剂中，有助于获得狭窄对称的峰。该在线 SPDE-UHPSFC-MS/MS 系统首次应用于人体尿液中 45 种禁用物质的筛选，对在线系统的所有机制和特征进行了全面研究。大部分（91%）目标化合物的基质效应较弱（80-120%），表明在线方法准确可靠，这得益于 SPDE 程序和高效 UHPSFC 分离。由于基质效应的降低、大体积进样和柱前稀释，该在线系统可以达到高灵敏度，LOD 范围为 0.0380ng/L-1.24μg/L。在优化条件下，66%目标分析物的提取回收率大于 50%。所有目标化合物均表现出良好的线性关系，线性相关系数均大于 0.9928。所有加标禁用物质的准确度值均在 80.8%-119.7%范围内，日内和日间精密度的 RSD%均在 10.8%-15.4%范围内。与简单稀释后分析尿液样品的稀释-进样-超高效液相色谱-MS/MS 方法相比，该在线方法在灵敏度和降低基质效应方面具有优势，证明了其在兴奋剂控制中的应用。与之前报道的在线 SPE-SFC 系统相比，在线 SPDE-UHPSFC-MS/MS 系统在自动化、效率、灵敏度和色谱性能方面具有优势。综上所述，该在线 SPDE-UHPSFC-MS/MS 系统能够分析复杂的水性样品。
