大学化学 >> 2018, Vol. 33 >> Issue (5): 51-55.doi: 10.3866/PKU.DXHX201801012

师生笔谈 上一篇    下一篇

分析化学中“检出限”的物理意义及测定方法探究

杨淳3,郑姗1,刘洋1,施娅颖1,黄朝表1,2,*()   

  1. 1 浙江师范大学化学与生命科学学院, 浙江 金华 321004
    2 浙江师范大学行知学院, 浙江 兰溪 321100
    3 诸暨中学, 浙江 诸暨 311800
  • 收稿日期:2018-01-08 发布日期:2018-05-18
  • 通讯作者: 黄朝表 E-mail:hcb@zjnu.cn
  • 基金资助:
    国家自然科学基金面上项目(21575129)

Study on the Physical Meaning and Determination Method of "Detection Limit" in Analytical Chemistry

Chun YANG3,Shan ZHENG1,Yang LIU1,Yaying SHI1,Chaobiao HUANG1,2,*()   

  1. 1 College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, Zhejiang Province, P. R. China
    2 College of XingZhi, Zhejiang Normal University, Lanxi 321100, Zhejiang Province, P. R. China
    3 Zhuji High School, Zhuji 311800, Zhejiang Province, P. R. China
  • Received:2018-01-08 Published:2018-05-18
  • Contact: Chaobiao HUANG E-mail:hcb@zjnu.cn
  • Supported by:
    国家自然科学基金面上项目(21575129)

摘要:

阐述了分析化学中各类分析方法的检出限的物理意义、测定方法及可能存在的问题,并论述了经典的检出限定义的局限性。在利用凝血酶适配体与凝血酶的特异性结合抑制Pt纳米颗粒对量子点荧光猝灭检测凝血酶和基于CuGeO3纳米线和葡萄糖氧化酶(GOx)修饰的玻碳电极(GCE)生物传感器测定葡萄糖的分析方法中,由于测定信号与被检测物质浓度或浓度的对数成负相关关系,导致分析方法的检出限与经典的检出限测定产生一定的冲突,出现了测定精密度越高,检出限越差的异常情况。

关键词: 检出限, 物理意义, 测定方法

Abstract:

In this paper, we studied the physical meaning, measurement methods and potential problems of detection limit in analytical chemistry. The limitation of classical detection limit was also discussed. We studied the detection of thrombin by fluorescence quenching of Pt nanoparticles, based on the specific binding of thrombin aptamer to thrombin. We found a negative correlation between the measured signal and the logarithm of the concentration. In addition, the similar negative correlation was found in the determination of glucose by a glassy carbon electrode biosensor, based on CuGeO3 nanowires and glucose oxidase. The detection limit of the above two method conflicted with the classical detection limits. It appeared abnormal that the better the determination precision, the worse the detection limit.

Key words: Detection limit, Physical meaning, Determination

MSC2000: 

  • G64