摘要
为了建立一种测定烟叶中总氮的新方法,此文对化学发光法测定烟叶中总氮进行了研究。将烟叶经消化后,采用改进的蒸馏装置进行加碱蒸馏,用硫酸吸收,将烟叶中的含氮化合物全部转化为氨态氮。根据NH4+在碱性溶液中能还原ClO-,该反应和化学发光反应ClO--Luminol相耦合,从而降低ClO--Luminol反应的化学发光强度,达到测定NH4+的目的。此方法的检测下限达到10-3mg/kg,线性范围选择在0.01～1.5mg/kg,加标回收率在87.3%～109.9%之间,此方法测定的14个烟叶样品铵态氮数据和采用凯氏定氮法测定的结果相比较,RSD<5%(n=5),完全能满足烟叶中总氮测定的要求。
In order to established a new method for determining the total nitrogen of tobacco, we studied the method of total nitrogen in tobacco by chemiluminescence. The tobacco leaves was digested, distilled with alkali by an improved distillation device, and absorbed by sulphuric acid, all the compounds which contain nitrogen in tobacco leaves change to ammonium nitrogen. NH4＋ can deoxidize ClO-in alkaline solution. This reaction couples with chemiluminescence reaction ClO--Luminol, which reduce the strength of luminosity. So that the content of the NH4＋is determined. The lower limit of detection reaches to 10-3 mg/kg. The choice of the line range is from 0.01 mg/kg to 1.5 mg/kg. The recovery of the method was 87.3%-109.9%. We measured the total nitrogen of the 14 tabacco samples by this method, We compared the results with Kjeldahl Nitrogen Method, RSD 5% （n = 5）, These conditions are completely contented with the requirement of determination of the total nitrogen in tobacco.
出处
《中国农学通报》
CSCD
北大核心
2010年第17期121-124,共4页
Chinese Agricultural Science Bulletin
基金
国家烟草专卖局科技项目(110200601015)
关键词
化学发光
烟叶
总氮
chemiluminescence
tobacco leaves
total nitrogen
