application of nano-sized poly (n-methyl pyrrole-pyrrole) fiber to the headspace solid-phase microextraction of volatile organic compounds from yogurt

a new poly (n-methyl pyrrole-co-pyrrole) (p-nmpy-co-py) coated flexible polyester fiber was provided by chemically-deposition of p-nmpy-co-py on the surface of polyester fiber in the mixed electrolytes of sodium dodecyl sulphonate (sds) and fecl3 (as an oxidant). the scanning electron microscopy (sem) and fourier transform infrared spectroscopy (ftir) were used for characterization of morphology, size, porosity and composition of synthesized copolymer. the nanosized and spheral p-nmpy-co-py particles are observed according to the sem results. the p-nmpy-co-py fiber was employed to extraction of volatile organic compounds (vocs) in yogurt samples as an extractor.

an experimental design was utilized to optimize operational parameters that affect the analysis of vocs in yogurt samples using headspace solid phase microextraction (hsspme) in the pre-concentration step. some parameters including, sample ph, temperature, ionic strength (nacl percent w/w %) were optimized. gas chromatography-flame ionization detection (gc-fid) was used for separation, detection and quantitation of vocs. results show that p-nmpy-co-py modified polyester fiber is provided fast and easily by chemical method and is suitable for the successful extraction of the vocs from yogurt samples.