单扫描示波极谱法测定阿司咪唑

Nitrasotion of Astemizole Followed by Its Determination Using Single-sweep Oscillopolarography

利用阿司咪唑与亚硝酸钠在 ０．１２ｍｏｌ／Ｌ ＨＡｃ介质中反应，其亚硝化产物于－０．７２Ｖ（ｖｓ．Ａｇ／ＡｇＣｌ）产生极谱还原波。该还原波的一阶导数峰电流与阿司咪唑浓度在 ４．０ × １０－７～ １．６ × １０－５ ｍｏｌ／Ｌ范围内呈线性关系（ ｒ＝ ０．９９９７）；检测限为 ２．０ × １０－７ｍｏｌ／Ｌ。用于片剂中阿司咪唑的测定，结果满意。

Astemizole is nitrasoted with sodium nitrite in 0. 12 mol/L HAc solution at boiling bath for 25 min. The nitrosation product of astemizole shows a reduction peak by single-sweep oscillopolarography. The peak potential is - 0. 72V (vs. Ag/AgCl). The first-order derivative peak current is proportional to the concentration of astemizole in the range of 4.0 × 10-7 - 1 .6 × 10-5 mol/L (r = 0.9997), with detection limit of 2.0 × 10-7 mol/L. The proposed method has been applied to the determination of astemizole in pharmaceutical tablets.