有机改性溶胶—凝胶传感膜检测亚硝酸根

An organically modified sol-gel sensing film for detection of nitrite

以二甲基二乙氧基硅烷与四乙氧基硅烷为有机-无机复合前驱体，番红花红为敏感指示剂，利用溶胶-凝胶法研制出有机改性传感膜。实验结果表明：在酸性条件下传感膜与亚硝酸根作用，导致吸光度降低，且在一定范围内与亚硝酸根浓度呈良好的线性关系（R=0．9929），线性范围为0．001—0．1mg·L-1，检出限为3×10 -4mg·L-1，响应时间小于1min。该传感膜具有选择性高、稳定性和重复性好的特点。

An organically modified sensing film was prepared by sol-gel method, using Dimthyldimethoxysilane and Tetraethoxysilane as the organic-inorganic composite precursor, Crocus Red as the indicator. The experimental result shows that sensing film reacted with nitrite in the acidic medium, causing a decrease in the absorbency of film. The sensing film has a good linear response （R =0. 992 9 ）to nitrite in a range of 0.1 -0. 001 mg · L-1 with a detection limit of 3 × 10-4 mg · L-1. The response time is less than 1rain. This sensing film shows high selectivity, well stability and repeatability.