Evaluation of dispersive and cartridge SPE clean-up procedures using the modified QuEChERS method for the analysis of pesticides in strawberries

Abstract

A comparison of dispersive and cartridge solid-phase extraction, d-SPE and c-SPE, respectively, for the clean-up step using the modified QuEChERS (quick, easy, cheap, effective, rugged and safe) method, followed by ultra-high performance liquid chromatography coupled with diode array detection (UHPLC-DAD) was carried out for the determination of pesticide residues in strawberries. Dry ice was used in the experiments for the evaluation of different temperatures. The efficiency of liquid-liquid partitioning step without salts was also evaluated. In all the experiments, the sorbent used in the clean-up step was primary secondary amine (PSA), and the evaluation of the sample preparation was made by the physical aspect of the final extract, the chromatographic profile, the recovery, the amounts of co-extractives in the matrix, which were determined by gravimetric measurements, and the matrix effect. A good cleanup procedure contributes to a longer lifetime of the chromatographic column and also for the entire system, and it also leads to better detectability for the developed method. Results showed that all the sample preparation methods were efficient for multiresidue pesticide analysis in this complex matrix, in which analytes with different physicochemical characteristics at low concentrations are present. The recovery results were in the range of 70-120%, and the coefficients of variation were #20% for most of the pesticides, as recommended for these analyses. The clean-up of the strawberry extracts was more efficient with the use of d-SPE at ambient temperature, considering the higher recoveries of the pesticides and better clean-up by removal of interferences; moreover, it was faster, easier and less expensive.

Organophosphorus Pesticide Multiresidues in Commercialized Asian Rice

“…The authors suggested that the SPE method is more reliable and sensitive for determining both LOD and LOQ with optimum extraction and clean‐up, especially those for target compounds that are of low abundance. The matrix effect throughout the SPE method can be minimized by considering DAD technology (Oshita and Jardim 2015). Compared with tandem mass spectrometry (MS/MS), which is traditionally associated with the QuEChERS method, DAD can overcome matrix effects by using curves with matrix‐matched standards, improving the clean‐up step, changing the blank matrix, modifying the detection wavelength, and optimizing chromatographic separation by using different analytical columns or gradient elution.…”

Quick, easy, cheap, effective, rugged, and safe sample preparation approach for pesticide residue analysis using traditional detectors in chromatography: A review

“…Cleanup prevents damage to the chromatographic system and reduces the need for maintenance, and also increases column application life. Moreover, detection has been achieved with a higher S/N and lower chance of false positives, both of which are attributed to matrix interference . HPLC coupled with a conventional UVD, DAD, and fluorescence detector (FLD) is a peerless chromatographic technique for thermolabile, polar, nonvolatile, and carbamate pesticides .…”

“…), a lot of interference was observed at the retention times of carbamate pesticides following the application of d‐SPE, whereas much cleaner chromatograms for green beans were provided after c‐SPE. Oshita and Jardim evaluated the d‐SPE and c‐SPE cleanup procedures using the modified QuEChERS method . For the cleanup employing a cartridge, the analytical signals showed lower matrix intensities when using a DAD as shown in Fig.…”

“…Chromatograms for blank samples (no fortification) obtained after different cleanup procedures with the modified QuEChERS method for strawberries .…”

Simultaneous Analysis of Ursolic Acid and Oleanolic Acid in Guava Leaves Using QuEChERS-Based Extraction Followed by High-Performance Liquid Chromatography

“…QuEChERS can serve as a template for modification because of its characteristic flexibility and can be adjusted for various matrices depending on the analyte properties, matrix composition, equipment, and analytical technique. Oshita and Jardim compared QuEChERS-based dispersive and cartridge SPE for the analysis of pesticides in strawberries and found that the QuEChERS-based dispersive SPE extraction clean-up of the strawberry extracts was more efficient, achieving higher pesticide recoveries and better clean-up via interference removal than those reported to date [ 12 ]. Tölgyessy et al have successfully applied the QuEChERS method with Dual dispersive SPE and gas chromatography to the determination of ten chlorinated priority substances in fish [ 13 ].…”