Use of phenyl/tetrazolyl-functionalized magnetic microspheres and stable isotope labeled internal standards for significant reduction of matrix effect in determination of nine fluoroquinolones by liquid chromatography-quadrupole linear ion trap mass spectrometry

• Published in: Analytical and bioanalytical chemistry 2018-02, Vol.410 (6), p.1709-1724
• Main Authors: Xu, Fei, Liu, Feng, Wang, Chaozhan, Wei, Yinmao
• Format: Article
• Language: English
• Subjects: Adsorbents; Adsorption; Analytical Chemistry; Anti-Bacterial Agents - analysis; Antibiotics; Biochemistry; Characterization and Evaluation of Materials; Chemical properties; Chemistry; Chemistry and Materials Science; Chromatography; Electrostatic properties; Fluoroquinolones; Fluoroquinolones - analysis; Food Analysis - methods; Food safety; Food Science; Hydrophobicity; Ions; Iron oxides; Laboratory Medicine; Limit of Detection; Linearity; Liquid chromatography; Magnets - chemistry; Mass spectrometry; Mass spectroscopy; Mathematical analysis; Matrix methods; Methods; Microspheres; Monitoring; Monitoring/Environmental Analysis; Pork; Quadrupoles; Red Meat - analysis; Research Paper; Scientific imaging; Silicon dioxide; Solid Phase Extraction - methods; Solid phases; Spectroscopy; Stable isotopes; Tandem Mass Spectrometry - methods
• ISSN: 1618-2642; 1618-2650
• DOI: 10.1007/s00216-017-0821-9

In this study, the strategy of unique adsorbent combined with isotope labeled internal standards was used to significantly reduce the matrix effect for the enrichment and analysis of nine fluoroquinolones in a complex sample by liquid chromatography coupled to quadrupole linear ion trap mass spectrometry (LC-QqQ LIT -MS/MS). The adsorbent was prepared conveniently by functionalizing Fe 3 O 4 @SiO 2 microspheres with phenyl and tetrazolyl groups, which could adsorb fluoroquinolones selectively via hydrophobic, electrostatic, and π–π interactions. The established magnetic solid-phase extraction (MSPE) method as well as using stable isotope labeled internal standards in the next MS/MS detection was able to reduce the matrix effect significantly. In the process of LC-QqQ LIT -MS/MS analysis, the precursor and product ions of the analytes were monitored quantitatively and qualitatively on a QTrap system equipped simultaneously with the multiple reaction monitoring (MRM) and enhanced product ion (EPI) scan. Subsequently, the enrichment method combined with LC-QqQ LIT -MS/MS demonstrated good analytical features in terms of linearity (7.5–100.0 ng mL -1 , r > 0.9960), satisfactory recoveries (88.6%–118.3%) with RSDs < 12.0%, LODs = 0.5 μg kg -1 and LOQs = 1.5 μg kg -1 for all tested analytes. Finally, the developed MSPE-LC-QqQ LIT -MS/MS method had been successfully applied to real pork samples for food-safety risk monitoring in Ningxia Province, China. Graphical abstract Mechanism of reducing matrix effect through the as-prepared adsorbent.