Determination of sixteen pyrethroids in water using dispersive liquid–liquid microextraction based on dissolved carbon dioxide flotation after emulsification microextraction using gas chromatography with triple quadrupole mass spectrometry†
Abstract
A method using dissolved carbon dioxide flotation after dispersive liquid–liquid microextraction (DCF-DLLME) was proposed for the determination of sixteen pyrethroids in water samples, coupled with gas chromatography with triple quadrupole mass spectrometry in a homemade glass round flask. The DCF-DLLME method is based on the rapid and simple phase separation of a low density organic solvent from the aqueous phase via introducing a saturated NaHCO3 solution into the acidified sample solution (0.10 mol L−1 CH3COOH) containing the analytes. The optimum extraction conditions used 45 μL of dodecanol and 2.6 mL of acetonitrile as the extraction and dispersive solvent respectively, with an extraction time of 40 s and a demulsification time of 80 s. The LOQ for the sixteen pyrethroids was 5 μg L−1 and the LODs were in a range between 0.87 and 1.39 μg L−1. The mean recoveries (n = 15) ranged from 79.6% to 98.2%, with the RSD (n = 15) data ranging from 2.7% to 8.5%. The method broke through the limit of volume for centrifugation, and the device is easy to clean and the volume of sample can be enlarged. Adequate analytical performance characteristics were obtained in terms of linear range and precision for sixteen pyrethroids in water. Satisfactory results were obtained in authentic samples. The results of analysis revealed that this method is simple, fast and environmentally friendly, being successfully applicable for the determination of sixteen pyrethroids in water samples.