烟碱石墨涂膜电极及PVC膜电极的研究

Studies on Nicotine Graphite Coated-Membrane and PVC Membrane Selective Electrodes

国内外现有的测定烟碱(尼古丁)的方法,都需要预先进行水汽带馏,再用重量法或分光光度法测定,重量法操作繁琐,分析一个样品需花30h,紫外分光光度法,仍必须预先进行水汽带馏,结果不够理想,目前国内药典还没有测定烟碱的方法。 本文采用四苯硼钠-烟碱为活性物的石墨涂膜电极及PVC膜电极,直接测定烟叶及香烟产品提取液中烟碱的含量,所得结果与重量法基本一致,该电极制作简便,电极响应快,线性范围较宽,选择性较好。

In this paper, the construction and analytical applications of tetraphenylboratc-nicotine graphite coated-membrane and PVC membrane selective electrodes arc described, These electrodes exhibit, near-Nernstian response to nicotine from 10^(-4) to 10^(-1)M, in the pH range of 6-7 and are sufficiently selective for the determination of nicotine in tobacco products without any prior separation. Comparing with all established methods, including liquid-membrane electrode method, this coated-membrane electrode potentiometric method is relatively simple, convenient and inexpensive construction, and gave satisfactory results.