Factorial design optimization of experimental variables in preconcentration of carbamates pesticides in water samples using solid phase extraction and liquid chromatography–electrospray-mass spectrometry determination

An experimental design was applied for the optimization of extraction process of carbamates pesticides from surface water samples. Solid phase extraction (SPE) of carbamates compounds and their determination by liquid chromatography coupled to electrospray mass spectrometry detector were considered. A two level full factorial design 2k was used for selecting the variables which affected the extraction procedure. Eluent and sample volumes were statistically the most significant parameters. These significant variables were optimized using Doehlert matrix. The developed SPE method included 200mg of C-18 sorbent, 143.5mL of water sample and 5.5mL of acetonitrile in the elution step. For validation of the technique, accuracy, precision, detection and quantification limits, linearity, sensibility and selectivity were evaluated. Extraction recovery percentages of all the carbamates were above 90% with relative standard deviations (R.S.D.) in the range of 3–11%. The extraction method was selective and the detection and quantification limits were between 0.1 and 0.5µgL−1, and 1 and 3µgL−1, respectively. [Display omitted] •Application of an experimental design for the optimization of extraction process of carbamates pesticides from surface water samples.•The most significant parameters were statistically eluent and sample volume.•Optimal working conditions were 143.5mL of water sample, 200mg of C-18 sorbent and 5.5mL of acetonitrile.•The optimized technique was validated in relation to accuracy, precision, detection, quantification limits, linearity, sensibility and selectivity.