A new Schiff's base ligand immobilized agarose membrane optical sensor for selective monitoring of mercury ion

作者：Alizadeh Kamal^*; Parooi Razieh; Hashemi Payman; Rezaei Behrooz; Ganjali Mohammad Reza

来源：Journal of Hazardous Materials, 2011, 186(2-3): 1794-1800.

DOI：10.1016/j.jhazmat.2010.12.067

• Optical sensor
• Mercury ion
• Agarose membrane
• Spectrophotometric

A highly selective optical sensor was developed for the Hg(2+) determination by chemical immobilization of 2-[(2-sulfanylphenyl)ethanimidoyl]phenol (L), on an agarose membrane. Spectrophotometric studies of complex formation between the Schiff's base ligand L and Hg(2+), Sr(2+), Mn(2+), Cu(2+), Al(3+), Cd(2+), Zn(2+), Co(2+) and Ag(+) metal ions in methanol solution indicated a substantially larger stability constant for the mercury ion complex. Consequently, the Schiff's base L was used as an appropriate ionophore for the preparation of a selective Hg(2+) optical sensor, by its immobilization on a transparent agarose film. A distinct color change, from yellow to green-blue, was observed by contacting the sensing membrane with Hg(2+) ions at pH 4.5. The effects of pH, ionophore concentration, ionic strength and reaction time on the immobilization of L were studied. A linear relationship was observed between the membrane absorbance at 650 nm and Hg(2+) concentrations in a range from 1 x 10(-2) to 1 x 10(-5) mol L(-1) with a detection limit (3 sigma) of 1 x 10(-6) mol L(-1). No significant interference from 100 times concentrations of a number of potentially interfering ions was detected for the mercury ion determination. The optical sensor was successfully applied to the determination of mercury in amalgam alloy and spiked water samples.

• 出版日期2011-2-28