Hollow fiber-based liquid phase microextraction coupled with high-performance liquid chromatography for extraction and determination of vitamin D3in biological fluids

摘要

The reliability of hollow fiber-based on using two immiscible organic solvents in the lumen and wall pores of hollow fiber was evaluated for extraction and preconcentration of trace amount of vitamin D3, prior to determination by HPLC-UV. The analyte was extracted from a 8-mL sample solution, into a thin layer of an organic solvent (n-dodecane) impregnated in hollow fiber pores, and finally back-extracted into a μL volume of organic solvent (acetonitrile) located inside the lumen of the hollow fiber. The effects of several factors such as the nature of organic solvent, hollow fiber length, stirring speed, extraction time, ionic strength, sample volume, and extraction temperature on the enrichment factors(EFs) were investigated. Under optimized conditions, the enrichment factor of 130, limit of detection (LOD) of 0.9ngmL-1 were obtained. The calibration curve was linear within the range of 3 to 1000ngmL-1 with reasonable linearity (R2=0.999). The percentages of relative within-day and between-day standard deviations (RSD %) based on six replicated determinations were 5.4 and 6.1, respectively. Finally, the feasibility of the proposed method was successfully evaluated by extraction, and determination of the analyte in the biological fluids and satisfactory results were obtained.