On-line multi-residue analysis of fluoroquinolones and amantadine based on integrated microfluidic chip coupled to triple quadrupole mass spectrometry
An on-line multi-residue qualitative and quantitative analysis of fluoroquinolones and amantadine in integrated microfluidic chip was developed prior to directly coupled to triple quadrupole mass spectrometry (QQQ-MS). Six parallel channels consisted of sample filtration units and micro solid phase extraction (micro-SPE) columns were performed simultaneously on the specifically designed microfluidic device. Firstly, the impurities in sample solution were trapped by the micropillar in the filtration unit. The solution passed through the micro-SPE units packed with hydrophilic lipophilic balance (HLB) particles, and then the two classes of drugs were enriched. After washing, the targets were eluted and immediately electrosprayed for MS analysis. This approach allowed effective filtration, enrichment, elution, and MS detection without the introduction of an additional separation step after SPE. Direct electrospray ionization (ESI)-MS at multiple reaction monitoring (MRM) mode could not only ensure the high sensitivity of quantitative analysis, but also achieved accurate qualitative analysis towards targets by MRM ratios, reducing the false positive. Good linear relationship were obtained by internal standard (IS) method with the linear range of 1-200 ng/mL(R2＞0.992). The mean recoveries of the eight target analytes were from 85.2 % to 122 % with the relative standard deviation (RSD) ranged from 5.6 % to 20.3 %. All this demonstrated that the developed microfluidic device could be a useful tool for rapid detection in the field of food safety.