一种测定主流卷烟烟气中固相自由基总量的新方法

A Novel Method for Quantitative Analysis of Total Particulate-phase Free Radicals in Mainstream Cigarette Smoke

研究了一种准确测定主流卷烟烟气中固相自由基总量的新方法.通常人们采用剑桥滤片来捕集主流卷烟烟气中的固相自由基,但它并不适合用于准确测定主流卷烟烟气中的固相自由基的总量,研究发现有超过20%的主流卷烟烟气中的固相自由基可以透过剑桥滤片.找到了一种电子顺磁共振波谱(EPR)信号很小的、适合用来捕集主流卷烟烟气中的固相自由基总量的过滤片.采用了以在相同条件下测得的1,1-二苯基-2-苦基肼基(1,1-Diphenyl-2-picryl-hydrazyl,简称DPPH)的EPR信号强度与强煤的EPR信号强度相比得到的相对EPR信号强度与自由基的自旋数建立校准曲线的方法来计算烟气固相自由基的量,降低了使用不同的电子自旋共振波谱仪造成的对同一种检测样品测定结果的差异.通过不同实验室内和实验室间的验证实验,证明了此方法有很好的重复性和重现性.

A method has been developed to accurately determine total particulate-phase free radicals in mainstream cigarette smoke. Cambridge filter pad （CFP） was usually employed to collect particulate-phase free radicals in mainstream cigarette smoke, but it was found that it was not suitable for the accurate determination of total particulate-phase free radicals in mainstream cigarette smoke. More than 20% of particulate-phase free radicals in the mainstream cigarette smoke were observed breaking through Cambridge filter pads in our experiments. A special filter pad with tiny electron paramagnetic resonance （EPR） signal was found out that was suitable for the quantitative analysis of total particulate-phase free radicals in the mainstream cigarette smoke. To reduce the difference between test results brought about by using different EPR spectrometers, a new calibration method was developed by using the ratios of EPR signal intensities of DPPH （1,1-diphenyl-2-picryl-hydrazyl） standard samples to those of high pitch and the spin number of the DPPH standard samples to make calibration curve. This method has been validated through intra- and inter-laboratory studies and has shown excellent repeatability and reproducibility.