title: Determination of thiamphenicol in honey by dispersive liquid-liquid microextraction with high-performance liquid chromatography.
abstract: Dispersive liquid-liquid microextraction (DLLME) coupled with high-performance liquid chromatography-variable wavelength detector (HPLC-VWD) was developed for extraction and determination of thiamphenicol (THA) in honey. A mixture of extraction solvent (30 microL 1,1,2,2-tetrachloroethane) and dispersive solvent (1.0 mL of acetonitrile) was rapidly injected into 5.00 mL sample solution for the formation of cloudy solution. The analyte in the sample was extracted into the fine droplets of C(2)H(2)Cl(4). After extraction, phase separation was performed by centrifugation, and the enriched analyte in the sedimented phase was determined by HPLC-VWD. Some important parameters, such as the kind and volume of extraction solvent and dispersive solvent, extraction time, sample solution pH, sample volume, and salt effect, were investigated and optimized. Under the optimum extraction condition, the method yielded a linear calibration curve in the concentration range from 3 to 2000 microg/kg for target analyte. The enrichment factors for THA was 87.9, and the limit of detection (S/N = 3) was 0.1 microg/kg. The relative standard deviation for the extraction of 10 microg/kg of THA was 6.2% (n = 6). The main advantages of DLLME-HPLC method are simplicity of operation, rapidity, low cost, high enrichment factor, high recovery, good repeatability, and extraction solvent volume at the microL level. Honey samples were successfully analyzed using the proposed method.
authors.affiliation: Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules & College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, China. hxch@hubu.edu.cn
authors.forename: Huaixia
authors.initials: H
authors.lastname: Chen
authors.forename: Hui
authors.initials: H
authors.lastname: Chen
authors.forename: Lei
authors.initials: L
authors.lastname: Liao
authors.forename: Jun
authors.initials: J
authors.lastname: Ying
authors.forename: Jianlin
authors.initials: J
authors.lastname: Huang
mesh_terms: D005591:Chemical Fractionation / Q000379:methods*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004980:Ethane / Q000031:analogs & derivatives; D005504:Food Analysis / Q000379:methods*; D006722:Honey / Q000032:analysis*; D006843:Hydrocarbons, Chlorinated; D006863:Hydrogen-Ion Concentration; D009994:Osmolar Concentration; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012965:Sodium Chloride; D013839:Thiamphenicol / Q000032:analysis* / Q000737:chemistry
chemical_list: D006843:Hydrocarbons, Chlorinated; C015530:1,1,2,2-tetrachloroethane; D012965:Sodium Chloride; D013839:Thiamphenicol; D004980:Ethane