溶胶凝胶法研制辛可宁电极

STUDY ON THE PREPARATION OF CINCHONINE ISE BY SOL-GEL TECHNIQUE

将Ag/AgCl电极于溶胶-凝胶溶液中反复浸3次以上,在室温静置48 h后在1.0×10-2mol·L-1辛可宁溶液中活化至少12 h即制成新型的辛可宁选择性电极.溶胶-凝胶溶液系将正硅酸乙酯、无水乙醇及0.1 mol·L-1盐酸按一定比例混合后加适量的硅钨酸作为活性物质,搅拌30 min混匀后在室温放置24 h配成.辛可宁电极在pH 6.0～7.0,辛可宁浓度在1.0×10-1～1.0×10-5mol·L-1范围内显示Nernst响应,平均斜率为57 mV/pc,检出限为8.0×10-6mol·L-1.

A new cinchonine ion selective electrode （ISE） was prepared by dipping the Ag/AgCl electrode into the sol-gel solution for more than 3 times, and then standing for 48 h at room temperature, and finally activating for at least 12 h in a 1.0 × 10^-2 mol· L^-1 cinchonine solution. The sol-gel solution was prepared by mixing ethyl orthosilicate, absolute alcohol and 0. 1 mol · L^-1 HCl in a definite proportion, and adding an appropriate amount of silicotungstic acid as active material, strring for 30 min and then standing for 24 h at room temperature. The new ISE showed Nernst response for cinchonine with an average slope of 57 mV/pc over the concentration range of 1.0× 10^-1～ 1.0 × 10^-5 mol · L^-1 at pH 6. 0-7. 0. Detection limit was found to be 8. 0 × 10^-6mol· L^-1.