Determination of neonicotinoid pesticides in propolis with liquid chromatography coupled to tandem mass spectrometry

Tomšič, Rok (author), Heath, David John (author), Heath, Ester (author), Markelj, Jernej (author), Kandolf Borovšak, Andreja (author), Prosen, Helena (author)

In this study, a method was developed for the determination of five neonicotinoid pesticides (acetamiprid, clothianidin, imidacloprid, thiacloprid, and thiamethoxam) in propolis. Two sample preparation methods were tested: solid-phase extraction and the quick, easy, cheap, effective, rugged, and safe (QuEChERS) method. The identities of analytes were confirmed using liquid chromatography–tandem mass spectrometry (LC-MS/MS) in the selected reaction monitoring mode. Solid-phase extraction resulted in cleaner extracts; therefore, the SPE-LC-MS/MS method was validated according to the SANTE protocol in triplicate at two spiking levels (10 ng/g and 50 ng/g). The average recoveries of analytes ranged from 61% to 101%, except for clothianidin (10–20%). The LOD ranged from 0.2 ng/g to 4.4 ng/g, whereas the LOQ was in the range of 0.8 ng/g–14.7 ng/g. In order to compensate for the matrix effect, matrix-matched calibration was used. Good accuracy (relative error: 1.9–10.4%) and good linearity (R$^2$ > 0.991) were obtained for all compounds. The optimised method was applied to 30 samples: 18 raw propolis and 12 ethanol tinctures. Acetamiprid, imidacloprid, and thiacloprid were detectable in seven samples but were still below the LOQ. This study is the first to report the determination of several neonicotinoid residues in propolis.

• Language: English
• Keywords: neonicotinoids, propolis, SPE, QuEChERS, LC-MS/MS
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FKKT - Faculty of Chemistry and Chemical Technology
• Publication status: Published
• Publication version: Version of Record
• Year: 2020
• Number of pages: 12 str.
• Numbering: Vol. 25, iss. 24, art. 5870
• PID: 20.500.12556/RUL-134670
• UDC: 543.544.5:543.51
• ISSN on article: 1420-3049
• DOI: 10.3390/molecules25245870
• COBISS.SI-ID: 42430723
• Publication date in RUL: 25.01.2022

Record is a part of a journal

• Title: Molecules
• Shortened title: Molecules
• Publisher: MDPI
• ISSN: 1420-3049
• COBISS.SI-ID: 18462981

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.
• Licensing start date: 11.12.2020

Secondary language

• Language: Slovenian
• Keywords: neonikotinoidi, propolis, SPE, QuEChERS, LC-MS/MS