Abdukader Abdukayum, Ailijiang Tuerdi and Muhetaer Tuerhong Pages 628 - 633 ( 6 )
Background: Nitrite is a carcinogenic compound and can be found in water, soil, and food products. Determining the presence of nitrite has become very important in monitoring water quality and food safety.
Methods: A highly sensitive optical chemical sensor based on sol-gel film for trace amounts of nitrite was developed. The Xylene cyanol FF dye doped organic-inorganic silica hybrid film was obtained by copolymerization of tetraethoxysilane (TEOS) with methyltriethoxysilane (MTEOS) as an organically modi ed sol-gel precursor, and deposited onto glass substrates using spin-coating techniques.
Results: The organically modified silicate thin film prepared with a 2:1 TEOS: MTEOS volume ratio was found to be the best in terms of transparency, uniformity, and stability. The organically modified silicate thin film changes from blue to yellow when added to a nitrite aqueous solution, causing decreased absorbance of the film at 618 nm. The experimental results show that the film has a good linear response (R2 = 0.9833) to nitrite in the range of 10 to 0.1 µg. L 1.
Conclusion: The XCFF dye doped sol-gel film has high sensitivity, selectivity for nitrite in the water samples. The detection limit of film for nitrite was found to be 0.011 µg. L 1 (0.24 nmol.L-1). This sol-gel film is stable, inexpensive, and easily fabricated. It could be practical used for the determination of nitrite in most real water samples.
Nitrite, optical sensor, organically modified silicate film, sol-gel, xylene cyanol FF dye.
College of Chemistry and Environmental Sciences, Laboratory of Xinjiang Native Medicinal and Edible Plant Resources Chemistry, Kashgar University, Kashgar 844007, P.R. China.