Determination of trace levels of aquaculture chemotherapeutants in seawater samples by SPME‐GC‐MS/MS

Abstract

A sensitive and efficient solid-phase microextraction (SPME) method for the determination of organophosphorous (OPPs) and pyrethroid pesticides (Pyrs) in aquaculture-seawater samples by using GC with MS/MS (GC-MS/MS) was developed. Dichlorvos and chlorpyrifos (OPPs); permethrin, alpha-cypermethrin and deltamethrin (Pyrs) were selected according to their use as chemotherapeutants in the aquaculture industry. Different parameters affecting extraction efficiency such as fibre coating, agitation, pH and extraction time profiles were investigated. An experimental central composite design (alpha = 1) and desirability functions were used for the simultaneous optimization of extraction temperature and sample volume. Finally, a method based on direct SPME in 40 min at 75 degrees C using 100-microm-thick poly(dimethyl)siloxane (PDMS) fibre and 20 mL of sample volume is proposed. The method was validated, exhibiting good linearity, precision and accuracy parameters with picogram per millilitre LODs. The proposed methodology was applied to determine the ultratrace levels of OPPs and Pyrs in aquaculture-seawater samples by the standard addition approach, which proved to be reliable and sensitive, in addition to requiring only small amounts of sample.

Analysis, occurrence, and toxic potential of pyrethroids, and fipronil in sediments from an urban estuary

“…It follows that the background associated with the sample matrix and the aforementioned co-elution issues account for the positive bias for ECD. Previous studies comparing different mass spectrometric configurations and operating modes (e.g., EI, NCI, and MS/MS) and ECD for analysis of pyrethroids concluded that sensitivity was similar but that the selectivity of NCI-MS and MS/MS was superior to ECD [8][9][10]17,22,23]. No such comparisons for fipronil were found in the literature.…”

Sorptive extraction techniques in sample preparation for organophosphorus pesticides in complex matrices

“…SPME technology can be performed in two ways: (1) direct immersion of the fiber into the aqueous sample to extract analytes dispersed in aqueous solution; (2) exposure of the fiber in the sample headspace to extract volatile targets that are partitioned between gaseous and liquid phases [54]. SPME has been applied to OPPs analysis in various matrices with high efficiency and good reproducibility [55][56][57][58][59][60][61][62][63][64][65][66][67][68][69][70][71].…”

Analysis of pesticide residues in seaweeds using matrix solid-phase dispersion and gas chromatography–mass spectrometry detection

“…Four different amounts of sample (0.2, 0.4, 0.6 and 1.0 g) were tested in order to minimise limits of detection and to check the roughness of the method using the GC-lECD system (García-Rodríguez, Carro, Lorenzo, Fernández, & Cela, 2008). In all cases, the seaweed samples were spiked with 100 ng g À1 , mixed with sodium sulphate anhydrous, keeping the ratio dispersant/sample at 4/1.…”