title: Alternative sorbents for the dispersive solid-phase extraction step in quick, easy, cheap, effective, rugged and safe method for extraction of pesticides from rice paddy soils with determination by liquid chromatography tandem mass spectrometry.
abstract: The clean-up step is essential to reduce interferences, improve quantification and help to maintain the integrity of the chromatographic system when working with complex matrices. In this study, alternative materials were evaluated as sorbents in the dispersive solid-phase extraction (D-SPE) for the determination and extraction of seventeen pesticides from rice paddy soil samples by the quick, easy, cheap, effective, rugged and safe (QuEChERS) method coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS). Chitin, chitosan, diatomaceous earth and PSA were compared in terms of extraction efficiency and matrix effect. The best results were achieved when chitosan was used. Quantification limits ranged from 0.1 to 100μgkg(-1). Calibration curves showed correlation coefficient values higher than 0.98. Results of accuracy and precision in the spiked soil samples between 60% and 120%, with a relative standard deviation lower than 20%, were reached for 15 out of 17 pesticides. The matrix effect was evaluated and only one compound was influenced by the matrix components, showing medium effect. Results showed that alternative materials are more effective and less expensive than traditional sorbents which have been usually employed, i.e., they may be used in the D-SPE step during the extraction of pesticides from rice paddy soils.
authors.affiliation: Post-graduate Program in Technological and Environmental Chemistry, Escola de Química e Alimentos, Laboratório de Análise de Compostos Orgânicos e Metais (LACOM), Universidade Federal do Rio Grande, Av Itália, km 8, Rio Grande, 96203-900 Rio Grande do Sul State, Brazil.
authors.forename: Jean Lucas de Oliveira
authors.initials: JL
authors.lastname: Arias
authors.affiliation: Post-graduate Program in Technological and Environmental Chemistry, Escola de Química e Alimentos, Laboratório de Análise de Compostos Orgânicos e Metais (LACOM), Universidade Federal do Rio Grande, Av Itália, km 8, Rio Grande, 96203-900 Rio Grande do Sul State, Brazil.
authors.forename: Caroline
authors.initials: C
authors.lastname: Rombaldi
authors.affiliation: Post-graduate Program in Technological and Environmental Chemistry, Escola de Química e Alimentos, Laboratório de Análise de Compostos Orgânicos e Metais (LACOM), Universidade Federal do Rio Grande, Av Itália, km 8, Rio Grande, 96203-900 Rio Grande do Sul State, Brazil.
authors.forename: Sergiane Souza
authors.initials: SS
authors.lastname: Caldas
authors.affiliation: Post-graduate Program in Technological and Environmental Chemistry, Escola de Química e Alimentos, Laboratório de Análise de Compostos Orgânicos e Metais (LACOM), Universidade Federal do Rio Grande, Av Itália, km 8, Rio Grande, 96203-900 Rio Grande do Sul State, Brazil. Electronic address: eprimelfurg@gmail.com.
authors.forename: Ednei Gilberto
authors.initials: EG
authors.lastname: Primel
mesh_terms: D002138:Calibration; D002851:Chromatography, High Pressure Liquid / Q000191:economics / Q000379:methods*; D012275:Oryza; D010575:Pesticides / Q000032:analysis*; D012987:Soil / Q000737:chemistry*; D052616:Solid Phase Extraction / Q000191:economics / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000191:economics / Q000379:methods*; D013997:Time Factors
chemical_list: D010575:Pesticides; D012987:Soil
keywords: Alternative sorbents; Dispersive solid-phase extraction; Liquid chromatography; Mass spectrometry; Multiple class pesticides; Rice paddy soil