Dunlop Allan J, Clunie Iain, Stephen Duncan W S, Allison James J
Department of Clinical Biochemistry, 1st Floor, Link Building, Aberdeen Royal Infirmary, Foresterhill, Aberdeen, AB25 2ZD, UK.
J Chromatogr Sci. 2014 Apr;52(4):351-6. doi: 10.1093/chromsci/bmt038. Epub 2013 Apr 26.
Cotinine is the primary metabolite of nicotine and the preferred biomarker for assessing cigarette smoke exposure. Several liquid chromatography-tandem mass spectrometry (LC-MS-MS) methods have been described for measuring cotinine in biological fluids. Sample preparation typically involves manual solvent evaporation and reconstitution steps. This study describes a novel LC-MS-MS method for the quantification of cotinine by using electrospray ionization with multiple reaction monitoring and cotinine-d3 as internal standard, coupled with an automated solid-phase extraction (SPE) procedure. The assay was linear over the analytical range of 0.5-1,000 ng/mL. The limits of detection and quantification were 0.13 and 0.20 ng/mL, respectively. Intra-assay and inter-assay imprecision of cotinine in all samples was <5 and <10% (coefficient of variation), respectively. The analytical recovery of cotinine spiked into plasma was >95-100%. Matrix effects in serum and plasma were <10%. A rapid, sensitive and specific LC-MS-MS method was developed and validated for the determination of cotinine in human plasma, using a straightforward automated SPE protocol. The application of this method to an epidemiological study has demonstrated its utility for batch analyses of a large sample set (>500 samples).
可替宁是尼古丁的主要代谢产物，也是评估接触香烟烟雾的首选生物标志物。已经描述了几种用于测量生物体液中可替宁的液相色谱 - 串联质谱（LC-MS-MS）方法。样品制备通常涉及手动溶剂蒸发和重构步骤。本研究描述了一种新型的LC-MS-MS方法，该方法使用电喷雾电离和多反应监测，以可替宁 - d3作为内标来定量可替宁，并结合了自动化固相萃取（SPE）程序。该测定法在0.5 - 1000 ng/mL的分析范围内呈线性。检测限和定量限分别为0.13和0.20 ng/mL。所有样品中可替宁的批内和批间不精密度分别<5%和<10%（变异系数）。添加到血浆中的可替宁的分析回收率>95 - 100%。血清和血浆中的基质效应<10%。开发并验证了一种快速、灵敏且特异的LC-MS-MS方法，用于测定人血浆中的可替宁，该方法使用了简单的自动化SPE方案。将该方法应用于一项流行病学研究已证明其在对大量样本集（>500个样本）进行批量分析时的实用性。
