Optical Chemical Sensor Based on 2,2-Furildioxime in Sol-Gel Matrix for Determination of Ni<SUP>2+</SUP> in Water

A new optical chemical sensor was fabricated based on incorporation of 2,2-furildioxime as a sensitive reagent into the nanopore of a transparent glasslike material through the sol-gel method which was suitable for determination of Ni2+ ions in aqueous solutions. The prepared sensors were composed of tetraethoxysilane (TEOS), 2,2-furildioxime, methanol, hydrochloric acid and Triton X-100. The sensors were constructed by dip coating onto glass substrates. The optimum response of the sensor toward Ni2+ ions was reached at pH 8.5 and the contact time for the formation of the complex at 10 min. The linear concentration of the calibration curve was in the range of 1-5 mg L-1 with a detection limit of 0.111 mg L-1, and quantification limit of 0.337 mg L-1. In addition, the relative standard deviation (RSD) was less than 5% in determination of Ni2+ with ten slide sensor membranes. The developed sensor was tested on Ni2+ determination in real water samples which was confirmed by the atomic absorption spectrophotometer method.