DETECTION OF FREE RADICALS IN TOBACCO SMOKE

这个子项目是许多利用资源的研究子项目之一 由NIH/NCRR资助的中心拨款提供。子项目的主要支持 而子项目的主要调查员可能是由其他来源提供的， 包括其它NIH来源。 列出的子项目总成本可能 代表子项目使用的中心基础设施的估计数量， 而不是由NCRR赠款提供给子项目或子项目工作人员的直接资金。 来自已故Ray Wu教授（康奈尔大学分子生物学和遗传学）小组的高级研究员Long Xi Yu对烟草烟雾中自由基的检测感兴趣。该研究项目的目的是找到一种香烟过滤嘴的处理方法，可以降低烟草烟雾中的自由基浓度，从而减轻吸烟的有害影响。经过大量实验，我们选择了在有机溶剂中使用BPN（N-叔丁基苯基硝酮）的自旋捕获技术来检测自由基。我们发现，在捕获之前从分析的烟雾中去除冷凝水是获得可重复的定量结果的关键。对于ESR测量，将溶剂脱氧。 我们发现了几种天然和人工抗氧化剂处理香烟过滤嘴，导致烟草烟雾中的自由基含量大幅减少。然而，在储存处理过的香烟时，自由基的水平逐渐恢复到未处理香烟的对照水平。这项工作正在进行中，以寻找一种持久的治疗方法，以供可能的商业应用。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Long Xi Yu, a senior research associate from the group of the late Prof. Ray Wu (Cornell University, Molecular Biology and genetics) is interested in the detection of free radicals in tobacco smoke. The aim of this research project is to find a treatment for cigarette filters which reduces the concentration of free radicals in the tobacco smoke and thus ameliorate harmful effects of smoking. After a number of experiments we chose for detection of free radical a spin-trapping technique using BPN (N-tert- Butil-phenylnitrone) in organic solvents. We found that the removal of water condensation from the analyzed smoke before trapping is key for obtaining reproducible quantitative results. For ESR measurements the solvents were deoxygenated. We found several natural and artificial antioxidant treatments for cigarette filters which cause substantial reduction of the free radical content in the tobacco smoke. However, upon storage of treated cigarettes the levels of free radical gradually returns to the control levels for untreated cigarettes. The work is in progress to find a durable treatment for possible commercial applications.