Multivariate optimization for extraction of pyrethroids in milk and validation for GC-ECD and CG-MS/MS analysis.
A simple and inexpensive method based on solvent extraction followed by low temperature clean-up was applied for determination of seven pyrethroids residues in bovine raw milk using gas chromatography coupled to tandem mass spectrometry (GC-MS/MS) and gas chromatography with electron-capture detector (GC-ECD). Sample extraction procedure was established through the evaluation of seven different extraction protocols, evaluated in terms of analyte recovery and cleanup efficiency. Sample preparation optimization was based on Doehlert design using fifteen runs with three different variables. Response surface methodologies and polynomial analysis were used to define the best extraction conditions. Method validation was carried out based on SANCO guide parameters and assessed by multivariate analysis. Method performance was considered satisfactory since mean recoveries were between 87% and 101% for three distinct concentrations. Accuracy and precision were lower than ±20%, and led to no significant differences (p < 0.05) between results obtained by GC-ECD and GC-MS/MS techniques. The method has been applied to routine analysis for determination of pyrethroid residues in bovine raw milk in the Brazilian National Residue Control Plan since 2013, in which a total of 50 samples were analyzed.
Laboratório Nacional Agropecuário, Ministério da Agricultura, Pecuária e Abastecimento, Estrada da Ponta Grossa, 3036 Porto Alegre, RS 91785-340, Brazil. leo.z.m.rs@gmail.com.
Leonardo Zanchetti
LZ
Meneghini
Laboratório Nacional Agropecuário, Ministério da Agricultura, Pecuária e Abastecimento, Estrada da Ponta Grossa, 3036 Porto Alegre, RS 91785-340, Brazil. grubensam@yahoo.com.
Gabriel
G
Rübensam
Laboratório Nacional Agropecuário, Ministério da Agricultura, Pecuária e Abastecimento, Estrada da Ponta Grossa, 3036 Porto Alegre, RS 91785-340, Brazil. vinibicca@yahoo.com.br.
Vinicius Claudino
VC
Bica
Laboratório Nacional Agropecuário, Ministério da Agricultura, Pecuária e Abastecimento, Estrada da Ponta Grossa, 3036 Porto Alegre, RS 91785-340, Brazil. ana.bergold@ufrgs.br.
Amanda
A
Ceccon
Laboratório Nacional Agropecuário, Ministério da Agricultura, Pecuária e Abastecimento, Estrada da Ponta Grossa, 3036 Porto Alegre, RS 91785-340, Brazil. fabiano.barreto@agricultura.gov.br.
Fabiano
F
Barreto
Instituto de Química, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves, 9500 Bairro Agronomia, Porto Alegre, RS 91501-970, Brazil. mfferrao@gmail.com.
Marco Flores
MF
Ferrão
Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul, Av. Ipiranga, 2752 Porto Alegre, RS 90610-000, Brazil. ana.bergold@ufrgs.br.
Ana Maria
AM
Bergold
D000818:Animals; D002849:Chromatography, Gas; D004784:Environmental Monitoring / Q000379:methods*; D004785:Environmental Pollutants / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry; D007306:Insecticides / Q000032:analysis; D008892:Milk / Q000737:chemistry*; D015999:Multivariate Analysis; D011722:Pyrethrins / Q000032:analysis* / Q000302:isolation & purification; D053719:Tandem Mass Spectrometry
D004785:Environmental Pollutants; D007306:Insecticides; D011722:Pyrethrins