Electrospun nanofibers as a new solid phase microextraction coating for determination of volatile organic impurities...

In this study, preparation of a solid-phase microextraction fiber of polydimethylsiloxane (PDMS) polymer in its blends with polystyrene (PS) via electrospinning process, on a stainless steel wire has been reported. The electrospining enhancement of PDMS solutions in the presence of PS is found due to the increase in the viscosity of the mixed solutions. Characteristics of the fibers were inspected by energy dispersive X-ray spectroscopy, scanning electron microscopy and field emission scanning electron microscopy. The applicability of the coating was assessed for headspace solid phase microextraction (SPME) of some residual solvents (Diethyl Ether, Toluene and Chloroform) from biological products (Anti venin and Foot-and-mouth disease vaccine) followed by gas chromatography-mass spectrometry. The effects of extraction time and temperature, desorption time and temperature, agitation rate and ionic strength on the extraction efficiency were investigated. Under optimized conditions, limits of detection in the range of 2-10 µg L^-1 and limits of quantification in the range of 10-50 µg L^-1 were obtained. The method showed linearity in a wide range with a correlation coefficient greater than 0.99. In addition, the obtained inter-day and intra-day precisions were in the range of 1.57-8.28% and 4.87-11.72%, respectively. The thermal stability of the fiber was also investigated and it was found to be durable at 230 °C for 450 min. Furthermore, the proposed method was successfully applied for quantification of chloroform in Foot-and-mouth disease vaccine and diethyl ether and toluene in Anti-venin with recoveries in the range of 78.84-123.01%.