聚苯胺修饰碳纤维超微pH传感器研究及其在植物柱头活体测试中的应用

A pH ultramicrosensor based on polyaniline film modified carbon fiber microcylinderelectrode in proposed. The film is introduced onto carbon fiber surface by electropolymerization of aniline, The sensor exhibits a linear response over the range 2～12. 5 pH, with a near Nerstain response slope (60 mV/pH) at room remperature. The correlation coefficientis 0. 999 9. The average response time at the sensor is about 2 min. The selectivity coefficient obtained for are - l1. 9, - 12. 1, - l2. O and -11' 6 for K+, Na+, Li+ and Ca2+, respectively. The sensor was employed for measuring the pH of tap water, lake water and fresh urine. The results obtained from the sensor are in good agreement with those from the glass pH electrode. The sensor has been used for in vivo detection of pH on surface microenvironment of Brassica stigmata and pollen grains with satisfactory results.