Microwave-assisted-demulsification dispersive liquid-liquid microextraction for the determination of triazole fungicides in water by gas chromatography with mass spectrometry.

A novel microwave-assisted-demulsification dispersive liquid-liquid microextraction technique was established for determination of three triazole fungicides in environmental water samples by gas chromatography with mass spectrometry. Importantly, microwave irradiation has been applied in demulsification to achieve the phase separation and enrichment of triazole fungicides in water samples successfully with low-density toluene as extractant. The experimental variables, including microwave power, microwave time, ultrasonic time, type and volume of extraction solvent, and effect of salting out were investigated. Under the optimized conditions, the method showed good linearity for myclobutanil, tebuconazole, and difenoconazole in the range of 1-100 μg/L. The limits of detection and the limits of quantification were within the range of 0.14-0.27 and 0.47-0.90 μg/L, respectively. The suitable enrichment factors for three triazole pesticides were in the range of 425-636. The recoveries were between 89.3 and 108.7%, and the relative standard deviations were from 5.4 to 8.6%. Finally, environmental water samples were used to verify the applicability of the proposed method for analysis of triazole fungicides targets. It can be concluded that the developed microwave-assisted-demulsification dispersive liquid-liquid microextraction gas chromatography with mass spectrometry method was a rapid, efficient, reliable, and environmental friendly way for analysis of triazole fungicides in water.