Analysis of ethanol and methanol in human body fluids by headspace solid phase microextraction coupled with capillary gas chromatography.

A new method for extraction and analysis of ethanol and methanol in human whole blood, urine and saliva samples based on headspace solid phase microextraction (SPME) using silver sulfide (Ag(2)S) and polyvinyl chloride (PVC) coated on silver wire is described. Unlike commercial fibers, which are coated on fused silica, the proposed fiber has a metallic base to which the coating adheres very strongly. Due to metallic base, this fiber is very durable and is thermally stable up to 250 degrees C. After optimization of coating composition and microextraction conditions, the fiber was used for sampling of methanol and ethanol from human body fluids prior to capillary gas chromatographic analysis. The high recovery (>94%), low detection limits (5.6 mg/L for ethanol and 12.8 mg/L for methanol) and excellent linearity (>0.9900) of calibration graphs made the proposed method suitable for this purpose.