Surfactant–Solvent-Based Quaternary Component Emulsification Microextraction Followed by High-Performance Liquid Chromatography for the Simultaneous Analysis of Benzimidazole Anthelmintics in Milk Samples

A simple surfactant-solvent-based quaternary component emulsification microextraction (SSEME) method combined with high-performance liquid chromatography–photodiode array detection has been developed for the extraction, preconcentration, and determination of four benzimidazole anthelmintic (i.e., oxfendazole, mebendazole, albendazole, and fenbendazole) residues in milk samples. The quaternary component solvent of SSEME carried out in 10 mL aqueous solution were Triton X-114 (emulsifier or carrier), acetonitrile (disperser solvent), and 1-octanol (extraction solvent). The surfactant has an important role in the enhancement of the extraction efficiency of the high polar analytes. For milk sample analyses, linearity was obtained in the range of 10–200 μg/L with the determination coefficients (R ²) higher than 0.996. Preconcentration factor was obtained in the range of 21–38, corresponding to limits of detection in the range of 2.6–9.9 μg/L. Intra-day (n?=?6) and inter-day (n?=?6?×?3) precisions in the sample studied were obtained with relative standard deviation below 8.8 %. The recoveries for the spiked target anthelmintics at different concentrations (25, 50, 100, and 150 μg/L) were obtained in the range 80.1–114.1 %. The proposed SSEME method has been demonstrated that is simple, effective, and reliable for the analysis of analytes in the samples studied and can be used as an alternative green analytical technique for benzimidazole analysis.     

Preconcentration and Simultaneous Analysis of Benzimidazole Anthelmintics in Milk Samples by Ultrasound-Assisted Surfactant-Enhanced Emulsification Microextraction and High-Performance Liquid Chromatography

The proposed ultrasound-assisted surfactant-enhanced emulsification microextraction (UASEME) coupled with high-performance liquid chromatography-photodiode array detection (HPLC-PDA) has been developed for the preconcentration and simultaneous analysis of five benzimidazole anthelmintics. Dichloromethane (extraction solvent) and Triton X-114 (emulsifier) was used for extraction of the target analytes. The parameters affecting the extraction efficiency were investigated and optimized. Under the optimum conditions, linearity was in the range from 10 to 150 μg?L^?1 with good coefficients of determination (R ²) higher than 0.994. Preconcentration factors were obtained up to 60, corresponding to limits of detection range of 1.8???3.6 μg?L^?1. Intra-day (n?=?5) and inter-day (n?=?4?×?3) precisions were obtained with relative standard deviation of retention time and peak area below 0.8 and 9.2 %, respectively. Good recoveries for the spiked target anthelmintics at different concentrations (e.g., 20, 50, and 100 μg?L^?1) of milk samples were obtained in 72.5–113.5 %. The results demonstrated that the proposed UASEME-HPLC-PDA can be used as an alternative powerful method for the simultaneous determination of the target analytes in milk samples.     

Preconcentration and Simultaneous Determination of Heterocyclic Aromatic Amines in Grilled Pork Samples by Ion-Pair-Based Surfactant-Assisted Dispersive Liquid-Liquid Microextraction and High-Performance Liquid Chromatography

An effective ion-pair-based surfactant-assisted dispersive liquid-liquid microextraction combined with high-performance liquid chromatography (HPLC) has been evaluated for the extraction and preconcentration of four heterocyclic aromatic amines (i.e., 2-amino-3,4-dimethyl-3H-imidazo[4,5-f]quinoline (MeIQ); 2-amino-3,4,8-trimethyl-3H-imidazo[4,5-f]quinoxaline (4,8-DiMeIQx); 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP); and 1-methyl-9H-pyrido[3,4-B]indole (Harmane)). In the extraction method, sodium dodecyl sulfate (SDS) was used as both ion-pairing and disperser agent and 1-octanol was selected as extraction solvent. The effects of various parameters on the extraction efficiency such as kind and concentration of surfactant, kind and volume of extraction, salt addition, vortex extraction, and centrifugation time were investigated. Under the selected condition, the method provided high enrichment factor in the ranged of 124–145. Good linearity was 0.01–1000 μg kg^?1 with the correlation coefficient (R ²)?>?0.999. The limit of detection was 0.01 μg kg^?1 for all compounds. The matrix match calibration was used for quantitation of the target analytes in grilled pork samples. The proposed method was successfully applied to analysis of heterocyclic aromatic amines in grilled pork samples where good recoveries were obtained in the range of 90 and 106 %.     

Low Toxic Organic Solvent-Based Ultrasound-Assisted Emulsification Microextraction for the Residue Analysis of Benzimidazole Anthelmintics in Egg Samples by High Performance Liquid Chromatography

Preconcentration and determination of benzimidazole anthelmintics in egg samples has been successfully carried out using low-toxic organic solvent based ultrasound-assisted emulsification microextraction (UAEME) method coupled with high performance liquid chromatography (HPLC). A modified quick, easy, cheap, effective, rugged and safe (QuEChERS) was used for precipitating protein and fat in egg samples before subjecting it to UAEME–HPLC. In UAEME, 1-octanol was used as extraction solvent and MeOH (chosen disperser solvent) under ultrasound radiation assisted. Under the optimum condition chosen (60 μl of octanol, 250 μl of MeOH, and 4-min ultrasonication), extraction efficiency was obtained in the range of 30–95, depending on the analytes. Limits of detection (LODs) of the studied benzimidazoles in egg samples were 7.2–14.4 μg/kg. Satisfied recoveries evaluated at the four-level spiked concentrations (i.e., 25, 50, 100, and 150 μg/kg) were obtained between 74.3 and 112.9 with the relative standard deviation (RSD) less than 11.5 %. Precisions comprising intra-day and inter-day measurements were obtained with RSD below 9.0 %. Less consumption of low toxic organic solvents, simple, and effective are beneficial of the demonstrated method.