The Application Of Hollow Fibre-Liquid Phase Micro-Extraction On The Bioassay Experiment Of Oestrogen Chemicals

The object of this study was to improve pre-concentration techniques using hollow fibre protected-liquid phase micro-extraction (LPME) for its application on biotic samples and limited environmental samples provided in small volumes. Five parameters, including extraction time, type of solvent, extents of agitation, fibre length and salt content of HF-LPME were optimised for the yeast two-hybrid assay and gas chromatography-mass spectrometer (GC/MS) chemical analysis. The results of chemical analysis were compared to the results of a bioassay using the yeast two-hybrid system to analyse endocrine-disrupting chemicals (EDCs). For the yeast two-hybrid assay, the optimised parameters comprised of an extraction time of 40 min, toluene as the extraction solvent, a stirring rate of 500 rpm, a fibre length of 2.0 cm and a salt concentration of 20% (w/v). For GC/MS analysis, HF-LPME conditions were optimised with an extraction time of 40 min, toluene: dichloromethane at a ratio of 1 : 1 (v : v) as the extraction solvent, a stirring rate of 700 rpm, a fibre length of 2.0 cm and a salt concentration of 30% (w/v). The results indicated that fibre length, extraction time, and degree of agitation were major contributing parameters for HF-LPME in EDCs analysis. Consequently, bioassays such as yeast two-hybrid assay could be easily, rapidly, and inexpensively conducted with small volume of sample using HF-LPME for the measurement of oestrogenic activity.