On-site stir-blade microextraction combined with dual-polarity direct infusion mass spectrometry for analysis of atrazine, daidzein, and genistein in environmental water samples

Abstract

[eng] Integration has emerged as the latter driving force in the evolution of sample preparation, greening analytical measurements through the minimization of steps and their inherent required resources. This article presents the integration of sampling and extraction under a stir-blade microextraction format. For this purpose, commercial blades coated with hydrophilic-lipophilic balance (HLB) microbeads are stirred into the sample thanks to a 5 V demanding miniature motor placed in the cap of the sampling bottle. The broad extraction scope of the HLB sorptive phase, combined with the final analysis of the eluates by dual-polarity direct infusion mass spectrometry, enables the determination of atrazine, daidzein, and genistein (belonging to two different families of organic contaminants) in a single extraction. The portability of the device, as well as the stability of the analytes once extracted in the blade, open the door to the on-site extraction, simplifying the overall analytical procedure. This combination enabled the determination of both classes of pollutants with a limit of quantification of 0.75 µg·L-1 and an inter-day precision (expressed as relative standard deviation) better than 15.4 %. Finally, the potential for the application of this methodology in environmental analysis (river water samples) was demonstrated with relative recoveries in the range of 89 to 127 %. Moreover, the proposed method was evaluated in terms of analytical performance (RAPI), applicability (BAGI), and sustainability (AGREEprep) using the appropriate metric tools, exhibiting results that demonstrate its potential.