Analysis Of Neutral Aromatic Components From Cigarette Smoke By Isotope Dilution-Gas Chromatography-Mass Spectrometry Method

The method for analysis of 10 kinds of neutral trace aromatic components from cigarette smoke by stable isotope dilution-gas chromatography-mass spectrometry(SIDA-GC-MS)was developed.Meanwhile,the quantity of neutral aroma components was determined through internal standard curve method.Eight stable isotope labels were synthesized by stable isotope labeling materials and their purity were tested by high performance liquid chromatography(HPLC).Structures were characterized by IR,UV,HR-MS and NMR.As internal standards,10 isotopic labels(D5-benzaldehyde and Dg-isophorone were purchased from Reagent)were added to Cambridge filter.The aromatic components were extracted by simultaneous distillation and extraction method,we identified the corresponding 10 trace neutral aroma components.Finally,Comparing the properties of the compounds and the ion abundance of the characteristic fragments,the most suitable internal standard were selected from 10 isotope labels to determine the content of 26 important neutral aroma components in cigarette smoke.The main research and conclusions are as follows:(1)Eight stable isotope markers were synthesized by using stable isotope-labeled raw materials;the purity of the product,tested by HPLC with evaporative light scattering detector,were 99.00%,98.20%,98.46%,97.94%,95.89%,95.00%,99.20%,95.80%,respectively.The structure of product was characterized by UV,IR,HR-MS and NMR.The results showed that structures were correct and the purity meets the requirements of standard.(2)A method for analyzing 10 neutral trace aromatic components from cigarette smoke by SIDA-GC-MS was established.In the case of simplifying the pre-processing steps and having more interference,10 traces of neutral aroma components such as geranyl acetone were accurately identified by comparing of molecular ions,characteristic fragments and retention times of isotopic labels.At the same time,the isotopic internal standard effectively reduced the matrix effect and improved the recovery rate.The analyzing of the sample in SIM mode allows the target compound to be completely separated from the interference component to meet the quantitative analysis requirements.The quantitative analysis method has a great linear relationship,and the correlation coefficient r is greater than 0.9990.The detection limit(LOD)was 0.34?4.59 ?g/kg,and the limit of quantitation(LOQ)was 1.14?15.30 ?g/kg,which was much lower than the content of each component,indicating that the sensitivity of the method was high;the average recovery of each compound was 83.3%?106.6%,and the RSD was 0.15%?8.69%,indicating that the method has high accuracy and repeatability.10 neutral trace aromatic components were qualitatied by using this method for in the four finished cigarettes and 12 single cigarettes.(3)Comparing the properties of the compounds and the ion abundance of the characteristic fragments,the most suitable internal standard were selected from 10 isotopes markers to determine the content of 26 important neutral aroma components in cigarette smoke.The quantity of 26 neutral aroma components was determined through internalstandard curve method.The results show that the quantitative analysis method has great linear relationship,RSD was 0.14%?6.39%,less than 10%.Which showed greater than the trial processing method.The average recovery was 70.19%?99.82%,and LOD was 0.66?7.37?g/kg,LOQ was 2.2?24.27 ?g/kg.Iindicating,the method has higher sensitivity.Results also showed that the recovery rate of the 26 aroma components were higher than that ofprevious projects "the studies of tobacco important threshold" in some extent,which limonene,furan 2-acetyl groups,5-methyl furfural oxidation,caryophyllene,dihydro kiwifruit lactone content and recovery rate were higher,but the relative levels are the same,such as high content of components are limonene and 5-methyl furfural.Due to the selection of suitable internal standard,the loss of aroma components in the extraction efficiency and purification process can be corrected,and the matrix effect in the experiment can be effectively corrected,so that the measured content value was closer to the real value.it has important implications for determining of neutral aroma components in mainstream cigarette smoke and guiding cigarette flavoring and casing.