Determination of Multiple Pesticides in Human Blood Using Modified QuEChERS Method with Fe3O4 Magnetic Nanoparticles and GC–MS

Abstract

Pesticides are often involved in numerous acute and fatal poisonings. Patients’ blood samples may be sent to a toxicological laboratory for a poisoning diagnosis. This study proposes a gas chromatography-mass spectrometry (GC–MS) method for the determination of seven pesticides (malathion, methyl isofenphos, dichlorvos, chlorpyrifos, phenthoste, p,p′-DDD, p,p′-DDE) in human blood based on a quick, easy, cheap, effective, rugged and safe (QuEChERS) sample preparation method with Fe3O4 magnetic nanoparticles (MNPs) as the new adsorbing material. It proved that Fe3O4 MNPs have excellent adsorbent function while purifying the complex blood sample and it is simple to be separated from the extract. Under the optimum conditions, the detection limits of the proposed method for seven pesticides ranged from 0.011 to 0.163 µg mL−1. Good linearity (R value ≥0.9949) was achieved at concentration levels of 0.3–4.0 µg mL−1, and acceptable method recoveries were found in the range of 70.0–111.8% at different concentrations, with the relative standard deviations (RSD) less than 10.5%. In short, the QuEChERS method with Fe3O4 MNPs used for removing impurities improved the speed of sample pre-treatment and exhibited an enhanced performance in purifying. It can be applied for both forensic and clinical cases of accidental or suicidal poisoning with these pesticides.