Comparison of electrospray and UniSpray, a novel atmospheric pressure ionization interface, for LC-MS/MS analysis of 81 pesticide residues in food and water matrices

Abstract

In mass spectrometry, the type and design of ionization source play a key role on the performance of a given instrument. Therefore, it is of paramount importance to evaluate newly developed sources for their suitability to analyze food contaminants like pesticide residues. Here, we carried out a head-to-head comparison of key extraction and analytical performance parameters of an electrospray ionization (ESI) source with a new atmospheric pressure ionization source, UniSpray (US). The two interfaces were evaluated in three matrices of different properties (coffee, apple, and water) to determine if multiresidue analysis of 81 pesticides by QuEChERS extraction and LC-MS/MS analysis could be improved. Depending on the matrix and irrespective of the chemical class, US provided a tremendous gain in signal intensity (22- to 32-fold in peak area, 6- to 7-fold in peak height), a threefold to fourfold increase in signal-to-noise ratio, a mild gain in the range of compounds that can be quantified, and up to twofold improvement of recovery. UniSpray offered comparable linearity and precision of the analyses with ESI, and did not affect the ion ratio. A gain in sensitivity of many compounds was observed with US, but in general, the two ionization interfaces did not show significant difference in LOD and LOQ. UniSpray suffered less signal suppression; the matrix effect was in average 3 to 4 times more pronounced, but showed better values than ESI. With no effect on recovery efficiency, US improved the overall process efficiency 3 to 4 times more than ESI. Graphical abstract Electronic supplementary material The online version of this article (10.1007/s00216-019-01886-z) contains supplementary material, which is available to authorized users.

Monitoring and dietary risk assessment of 81 pesticide residues in 11 local agricultural products from the 3 largest cities of Cameroon

“…Pesticides extraction and dispersive solid phase extraction (d-SPE) clean-up were performed using the QuEChERS method, and analysis was done by LC-MS/MS previously developed and validated by (Galani et al, 2018). Details of the be found in (Galani, Houbraken, Van Hulle, & Spanoghe, 2019). The compliance of quantified pesticides with existing regulations was checked by comparing their residue level with European Union MRLs taken from the EU Pesticides Database (European Commission, 2020).…”

Magnetic amino‐functionalized hollow silica‐titania microsphere as an efficient sorbent for extraction of pesticides in green and roasted coffee beans

“…The efficiency and quantitative characteristics of the developed method were compared with other reported techniques for the determination of selected pesticides in different matrices (Table 3) [35–38]. As can be seen, despite the highly sensitive and selective detection systems used in previously reported methods, LOD and LOQ of the proposed method are lower than some methods and comparable with the others.…”

Mass Spectrometry as a Workhorse for Preclinical Drug Discovery: Special Emphasis on Drug Metabolism and Pharmacokinetics

“…Even though higher temperatures are employed, the actual temperature felt by analyte molecules is way lesser due to a phenomenon called evaporative cooling effect/evaporation enthalpy. Next, analyte molecules in gas phases were bombarded with electrons formed from corona discharge needle [26,27]. In positive mode primary ions such as N2 + are formed by electron impact.…”