Dispersive liquid–liquid microextraction coupled with high‐performance liquid chromatography‐diode array detection for the determination of N‐methyl carbamate pesticides in vegetables

Abstract

This paper described a simple, rapid and efficient method for the determination of N-methyl carbamate pesticides in tomato, cucumber, carrot and lettuce samples by dispersive liquid-liquid microextraction coupled with HPLC-diode array detection. Some experimental parameters that influenced the extraction efficiency, such as types and volumes of extraction and disperser solvents, extraction time and salt effect were examined and optimized. Under optimum conditions, the LOD of the method were 0.5-3.0 μg/kg depending on the compounds and the kind of vegetables. The linearities of the method were obtained in the range of 10.0-300 μg/kg for aldicarb, MTMC, carbofuran and carbaryl, and 20.0-600 μg/kg for isoprocarb, with the correlation coefficients ranging from 0.9921 to 0.9993. The RSD varied from 2.9 to 7.5% (n=5). The recoveries of the method for the five carbamates from vegetable samples at two different spiking levels were ranged from 77.8 to 98.2%. Results showed that the method we proposed can meet the requirements for the determination of N-methyl carbamate in vegetable samples and was finally applied to the analysis of target pesticides in vegetable samples taken from local markets.

High Density Solvent Based Dispersive Liquid-Liquid Microextraction Technique for Simultaneous and Selective Extraction of Multiclass Pesticide Residues in Water and Sugarcane Juice Samples

“…Since its introduction, the DLLME technique has been used for extraction of trace organic and inorganic pollutants such as polycyclic aromatic hydrocarbons, aromatic amines, metals, antioxidants and some class of pesticides; mainly from water [25] and to lesser extents in foods [26], especially in juices [27] and vegetables [28]. However, there are very few literature reports on application of the technique for determination of pesticides in waters [29] and none on the use of high density solvent based dispersive liquid-liquid microextraction (HD-DLLME), for simultaneous extraction of multiclass pesticide residues from water, of different sources, and sugarcane juice samples.…”

“…Furthermore, the disperser solvent should be miscible both in the organic and aqueous phases in order to form a distinct cloudy solution [28] [34].…”

Electrochemical sensor based on molecularly imprinted polymer reduced graphene oxide and gold nanoparticles modified electrode for detection of carbofuran

“…It can also shorten the crop growth period and increase crop yields. CBF can be detected by mass spectrometry [1], chromatography [2][3][4][5], gas chromatography-mass spectrometry [6,7], enzyme inhibition method [8,9], and sensor or biosensor [10][11][12][13]. However, these operations are usually time-consuming and require expensive instruments, with complicated process of sample pretreatment.…”

Automated optosensor for the determination of carbaryl residues in vegetable edible oils and table olive extracts

“…Carbaryl has been determined in a wide variety of samples, such as waters (Khodadoust and Hadjmohammadi, 2011), fruits (Santalad et al, 2009), vegetables (Lin et al, 2011) or meat (Biswas et al, 2010), being its MRLs regulated by government agencies of most countries.…”