University of Tabriz

About: University of Tabriz is a education organization based out in Tabriz, Iran. It is known for research contribution in the topics: Population & Nanocomposite. The organization has 12141 authors who have published 20976 publications receiving 313982 citations.

Modified Polypyrrole with Tetrasulfonated Nickel Phthalocyanine as a Fiber for Solid-Phase Microextraction. Application to the Extraction of BTEX Compounds from Water Samples

Abstract: Gold wire was coated with polypyrrole (PPY) by electropolymerization and used as a solid-phase microextraction (SPME) fiber. The adsorptive property of the coating was modified by doping with tetrasulfonated nickel phthalocyanine (NiPcTS). The efficiency and reliability of this fiber was investigated for the extraction of BTEX compounds from the headspace of water samples. Monitoring of extraction efficiency was performed by capillary GC-FID. Effects of several factors such as electropolymerization time, salt addition, exposure time and stirring speed on extraction efficiency were studied. The calibration graphs were linear in the range of 0.06 to 50 ng mL−1 and the detection limits for BTEX compounds were 20–50 pg mL−1. Comparing the results obtained using these fibers with results reported in the literature with polydimethylsiloxane (PDMS) fibers shows that under optimum conditions, the detection limits are comparable.

Carbon nanotube-ionic liquid (CNT-IL) nanocamposite modified sol-gel derived carbon-ceramic electrode for simultaneous determination of sunset yellow and tartrazine in food samples.

Abstract: Carbon-ceramic electrode modified with multi-walled carbon nanotubes–ionic liquid (MWCNTs–IL) nanocomposite was constructed. This electrode was used for electrochemical determination of food dyes Sunset Yellow (SY) and tartrazine (Tz). The modified electrode based on high surface area and high ionic conductivity of nanocomposite exhibited electrocatalytic effect for oxidation of SY and Tz; also, oxidation peak potentials of SY and Tz effectively separated on modified electrode, and their simultaneous determination was possible. Operational parameters, such as the amount of MWCNTs in suspension, IL volume, solution pH, and scan rate, which affect the analytical performance of determination, were optimized. The present electrode behaved linearly to Sunset Yellow and tartrazine in the concentration range of 4 × 10−7 to 1.1 × 10−4 M and 3 × 10−6 to 0.7 × 10−4 M with a detection limit of 10−7 M (0.045 mg L−1) and 1.1 × 10−6 M (0.59 mg L−1), respectively. The proposed method was successfully utilized for simultaneous determination of SY and Tz in different food samples, and the obtained results were in good agreement to those obtained by HPLC method.