刘威 涂安婷 徐其敏

摘要 [目的]对检测过程中工作曲线浓度范围的选取进行研究分析，以提高不同种类烟草制品中氨含量的测定准确性。[方法]将各类烟草制品按氨含量划分4个区域，并绘制3条浓度范围较小的工作标准曲线（0.2～2.0、1.0～10.0、10.0～100.0 mg/L）用于分析测定。[结果]工作曲线浓度范围对检测结果有显著影响，浓度范围越大则低浓度样品检测结果的准确度和精密度越低。检测结果RSDmax<0.9%，回收率在99.9%～100.7%，3个典型烟样氨含量的测量不确定度如下：烤烟1为（0.042 5±0.001 6）‰，香料烟为（0.437±0.012）‰，白肋烟1为（5.04±0.13）‰。[结论]上述区间划分合理，检测数据准确、可靠。

关键词 氨；工作曲线浓度范围；区间划分；不确定度

Analysis on Accuracy and Uncertainty in Determination of Ammonia in Different Kinds of Tobacco

LIU Wei， TU An-ting， XU Qi-min

（Huahuan International Tobacco Co.， Ltd.， Mentaizi Industrial Park of Fengyang County， Chuzhou， Anhui 233121）

Abstract [Objective] The aim was to study the concentration range of calibration curve to improve the accuracy of the determination of ammonia in different kinds of tobacco with continuous flow method. [Method] Three different calibration curves were drawn for determination of ammonia content in different tobacco and the concentration range of standard solution was 0.2-2.0 mg/L， 1.0-10.0 mg/L and 10.0-100.0 mg/L， respectively. The uncertainty of this measurement was analyzed and assessed. [Result] Tobacco products were divided into 4 groups according to ammonia content.The concentration range of calibration curve had a significant influence on the test results， that was the greater the concentration range， the lower the accuracy and precision of test results. The RSDmax was less than 0.9%， and the rate of recovery was 99.9%-100.7%. The uncertainty of this measurement were as followed： （0.042 5±0.001 6）‰ for flue-cured tobacco 1， （0.437±0.012）‰ for oriental tobacco， （5.04±0.13）‰ for burley 1. [Conclusion] The above interval differentiate was reasonable， and the detection data was accurate and reliable.

Key words Ammonia；Work curve concentration range；Interval differentiate；Uncertainty

氨是煙草中天然存在的成分，在烟草的燃吸过程中被释放出游离在烟气中，并与许多化合物发生作用，如可以与糖形成香味物质、可以增强烟碱的作用效果、调节烟气酸碱度，所以对卷烟制品的吃味质量和劲头有着重要影响[1-3]。准确地测定烟草中氨的含量，对于研究和了解卷烟的品质很有意义。

连续流动分析法是一种检测烟草化学成分含量的常规方法，其操作方便、准确高效。近几年来，大量研究报道了以该方法测定烟草内氨含量的优越性，并且国家烟草专卖局于2008年发布了行业标准《YC/T 245—2008 烟草及烟草制品 氨的测定 连续流动法》。

然而，笔者在检测过程中发现不同种类烟草中氨含量存在明显差异，最高超过1.00%，最低不足0.01%。目前，如何选取合适的工作曲线确保检测结果的准确性以及选取不当造成的影响的研究鲜见报道。鉴于此，笔者分析了工作曲线浓度范围对检测结果的影响，确定了合理的浓度范围，对不同种类烟草制品进行了区间划分，绘制了合适的标准工作曲线测定其氨含量，并评估了检测结果的精密度、准确性和不确定度。……