Development of a Quantitative and Sensitive Liquid Chromatographic/Mass Spectrome

研究得出结论，非洲裔美国人的戒烟率低于美国白人，尽管 这一群体每天抽的香烟比美国白人少(1比4)。此外，非洲 美国人与烟草相关的发病率高得不成比例(5-7)。我假设 非洲裔美国人可能更难戒烟，因为他们无法新陈代谢 尼古丁及其代谢物高效。因此，这项研究将试图确定是否存在 非裔美国人戒烟率与其尼古丁代谢特征之间的相关性。 这项研究项目将使用LC/MS来测量非裔美国人的尼古丁代谢谱 参加戒烟诊所。将开发一种改进的LC/MS方法，以增强 尼古丁及其主要代谢物可替宁、反式-3‘-羟基可替宁检测的灵敏度和准确性 N‘-氧化物尼古丁、4-羟基-4-(3-吡啶)-丁酸、尼古丁-A/-葡萄糖醛酸苷、可替宁-A/-葡萄糖醛酸苷和反式- 尿样中3‘-OH-可替宁-O-葡萄糖醛酸苷。改进的LC/MS方法将结合Q-TOF质量 相对于当前的LC/MS(ESI四极)，扩展了所开发方法的灵敏度和准确度 到目前为止在实践中使用的方法。该项目将专注于隔离来自非洲的尿样 参加戒烟诊所的美国人。样本将被分析，尼古丁水平 并对其主要代谢物可替宁进行了定量。再一次，研究项目将建立一个新陈代谢图谱 参加戒烟诊所的非裔美国人并调查是否有 戒毒率与代谢谱之间的相关性。 研究还得出结论，暴露在环境烟草烟雾(ETS)中的大部分是 非吸烟者中的癌症病例(8，9)。由于低水平的癌症导致烟草代谢物在 对于非吸烟者的尿样，需要一种可靠而简单的提取方法来测定尼古丁 代谢物。目前的提取方法过于繁琐和耗时。此外，由于 尼古丁的降解动力学和耗时的制备时间，提取方法可以 造成尿样中尼古丁含量测定的误差。这项研究项目将扩大研究范围 在PSCOM的陈刚博士的实验室进行，以及专注于开发一个健壮、可靠的 方法从非吸烟者尿液中提取尼古丁及其代谢物。这样做的主要目的是 研究项目的组成部分是为了使研究人员能够更好地熟悉程序 以及与开展临床研究和癌症相关研究相关的做法。的具体目标 本课题的研究内容如下： 具体目标： 1.建立使用四极飞行时间质谱仪(QTOF)的LC/MS定量方法 检测尿样中低水平的尼古丁及其主要代谢物。 2.应用发展的qTOF方法研究非裔美国人的代谢特征 试图戒烟。 3.建立从SHS患者尿样中提取尼古丁及其代谢物的较佳方法。 4.继续陈刚博士开发的现有研究和技术，以测量低水平的 环境烟草烟雾暴露对非吸烟者尼古丁及其代谢物的影响

Studies conclude that the cessation rates amongst African Americans are lower than White Americans despite the fact that this group smokes fewer cigarettes per day than White Americans (1-4). Furthermore, African Americans experience disproportionately higher rates of tobacco-related morbidity (5-7). I hypothesize that African Americans may have a more difficult time with quitting smoking because of their inability to metabolize nicotine and its metabolites efficiently. As a result, this research will attempt to determine if there is a correlation between smoking cessation rates amongst African Americans and their nicotinic metabolic profile. This research project will use LC/MS to measure the nicotinic metabolic profile of African Americans participating in smoking cessation clinics. An improved LC/MS method will be developed enhancing the sensitivity and accuracy of detection of nicotine and its major metabolites, cotinine, trans-3'-OH-cotinine, nicotine N'-oxide, 4-OH-4-(3-pyridyl)-butanoid acid, nicotine-A/-glucuronide, cotinine-A/-glucuroninde and trans- 3'-OH-cotinine-O-glucuronide, in urine samples. The improved LC/MS method will incorporate a q-TOF mass analyzer extending the sensitivity and accuracy of the developed method relative to the current LC/MS (ESIquadrupole) methods in practice to date. The project will focus on sequestering urine samples from African Americans participating in smoking cessation clinics. The samples will be analyzed and the levels of nicotine and its major metabolite, cotinine, quantified. Again, the research project will establish a metabolic profile of African Americans participating in a smoking cessation clinic and investigate whether or not there is a correlation between cessation rates and metabolic profile. Studies also conclude that exposure to environmental tobacco smoke (ETS) contributes to a majority of the cancer cases amongst non-smokers (8,9). Because of the low-levels of cancer causing tobacco metabolites in the urine sample of non-smokers, a reliable and simple extraction method is needed to measure nicotine metabolites. Current extraction methods are too cumbersome and time-consuming. Furthermore, because of the kinetics of degradation of nicotine and the time-consuming preparation times, the extraction methods can induce errors in quantitation of nicotine in urine samples. This research project will expand the studies conducted in the laboratory of Dr. Gang Chen at PSCOM, as well as focus on developing a robust, reliable method to extract nicotine and its metabolites from the urine of non-smokers. The main purpose of this component of the research project is so that the researcher can become better acquainted with the procedures and practices in place related to conducting clinical research and cancer related research. The specific aims of this research project are as follows: Specific Aims: 1. To develop a quantitative LC/MS method using a quadrupole time-of-flight mass spectrometer (qTOF) to detect low levels of nicotine and its major metabolites, in urine samples. 2. To apply the developed qTOF method to investigate the metabolic profile of African-Americans attempting to quit smoking. 3. To develop better extraction methods of nicotine and its metabolites from urine samples of SHS. 4. To continue existing research and technology developed by Dr. Gang Chen to measure low levels of nicotine and its metabolites in non-smokers (SHS) exposed to environmental tobacco smoke (ETS)