Ultrasonic Piezoelectric Nebulization of Propoxur for the Determination by Corona Discharge Ionization Ion Mobility Spectrometry

Abstract

Propoxur insecticide as a thermally unstable compound (decomposed at its boiling point) could not be analyzed by traditional sample introduction systems based on the thermal desorption. In this study, an ultrasonic piezoelectric nebulizing injection port was applied for evaporating this compound prior to its determination by corona discharge ionization ion mobility spectrometry (CD-IMS). The target analyte was extracted from different water samples by using the extraction method of dispersive liquid-liquid microextraction. Methanol and trichloromethane were utilized as the disperser and extraction solvents, respectively. The effective variables included the volume of the disperser and the extraction solvents, the pH, and the centrifugation time were studied by a Fractional Factorial Design to identify the important parameter(s) and their interaction. To that end, a Central Composite Design was performed to achieve optimum levels of each effective parameter. The results showed that the optimum conditions were 78 μL of the extraction solvent, and 1.2 mL for the disperser solvent; centrifugation time was 1 min at 1010g, and finally pH 7. A detection limit of 2.1 μg L-1 , a linear range of 2.5-80 μg L-1 , and a relative standard deviation of 7% were obtained. Different water samples were analyzed by the proposed technique, and the propoxur amounts were successfully determined. The obtained results revealed satisfactory relative recovery values of between 91 and 105%.

Assessment of Fenobucarb and Propoxur insecticides in environmental samples by spectrophotometric and spectrofluorimetric methods

“…Fenobucarb-2-sec-butylphenyl methylcarbamate, (Scheme 1) is a carbamate insecticide derived from carbamic acid and is used to control biting and sucking insects in rice, cotton and other crops (Zhu et Propoxur-2-isopropoxyphenyl methylcarbamate, (Scheme 1) is a non-systemic, broad-spectrum carbamate insecticide with a fast knockdown and long residual effect (Tabibi and Jafari 2006;Patel et al 2013;Yildiz et al 2017;Zheng 2017). It is used against a large variety of insects in agriculture, residential and non residential areas, in public health and for in and outdoor spraying (Tabibi and Jafari 2006;Patel et al 2013;Yildiz et al 2017). The oral LD 50 of propoxur for rats ranged from 40 to 150 mg/kg (Patel et al 2013).…”

“…The oral LD 50 of propoxur for rats ranged from 40 to 150 mg/kg (Patel et al 2013). On exposure it leads to inhibition of acetyl cholinesterase, leading to paralysis in insects and mammals, blurred vision, nausea, vomiting, sweating and tachycardia (Tabibi and Jafari 2006;Patel et al 2013).…”

“…Due to solubility of these insecticides in water, fenobucarb 420 mg/L at 20 o C and propoxur 1860 mg/ L at 30 o C (Pham et al 2021;Tabibi and Jafari 2006), they have the potential to enter the surface water through surface run off and also leach down into groundwater. This leads to their residues in different environmental segments and accumulation in humans and other non-target species, which causes potential hazard to human health and environment (Zheng 2017;Ma et al 2022;Lawrence et al 2009;Tada et al 2009).…”