Dispersive liquid–liquid microextraction followed by high-performance liquid chromatography as an efficient and sensitive technique for simultaneous determination of chloramphenicol and thiamphenicol in honey

• Published in: Analytica chimica acta Vol. 632; no. 1; pp. 80 - 85
• Main Authors: Chen, Huaixia, Chen, Hui, Ying, Jun, Huang, Jianlin, Liao, Lei
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 19.01.2009; Elsevier
• Subjects: Analytical chemistry; Chemistry; Chloramphenicol; Chloramphenicol - analysis; Chloramphenicol - chemistry; Chromatographic methods and physical methods associated with chromatography; Chromatography, High Pressure Liquid - instrumentation; Chromatography, High Pressure Liquid - methods; Dispersive liquid–liquid microextraction (DLLME); Exact sciences and technology; High-performance liquid chromatography; Honey - analysis; Honey sample; Hydrogen-Ion Concentration; Molecular Structure; Osmolar Concentration; Other chromatographic methods; Sample preparation; Sensitivity and Specificity; Solvents; Thiamphenicol; Thiamphenicol - analysis; Thiamphenicol - chemistry; Time Factors; Chloramphenicol; Dispersive liquid–liquid microextraction (DLLME); Sample preparation; Thiamphenicol; Honey sample; High-performance liquid chromatography; Water; Microanalysis; HPLC chromatography; Solvent extraction; Bulk effect; Chemical enrichment; Detection limit; Standard curve; Standard deviation; Sediments; Honey; Repeatability; Salt effect; Phase separation; Acetonitrile; Simultaneous measurement; Microextraction; Dispersive liquid-liquid microextraction; Recovery factor; DLLME
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2008.10.068

Dispersive liquid–liquid microextraction (DLLME) coupled with high-performance liquid chromatography-variable wavelength detector (HPLC-VWD) was developed for extraction and determination of chloramphenicol (CAP) and thiamphenicol (THA) in honey. In this extraction method, 1.0 mL of acetonitrile (as dispersive solvent) containing 30 μL 1,1,2,2-tetrachloroethane (as extraction solution) was rapidly injected by syringe into a 5.00-mL water sample containing the analytes, thereby forming a cloudy solution. After extraction, phase separation was performed by centrifugation and the enriched analytes in the sedimented phase were determined by HPLC-VWD. Some important parameters, such as the nature 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 yields a linear calibration curve in the concentration range from 3 to 2000 μg kg −1 for target analytes. The enrichment factors for CAP and THA were 68.2 and 87.9, and the limits of detection (S/N = 3) were 0.6 and 0.1 μg kg −1, respectively. The relative standard deviations (RSDs) for the extraction of 10 μg kg −1 of CAP and THA were 4.3% and 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 microliter level. Honey samples were successfully analyzed using the proposed method.