Tobacco Chemical Composition Characteristics Of Tobacco Organochlorine Pesticide Residue Analysis

An analytical method of tobacco chemical components based on GC/FID/MS and an GC/μECD/MS-SIM-based analytical method of organochlorine pesticides residuals in tobacco were developed.Firstly the operating conditions of ultrasonic solvent extraction and subcritical water extraction were optimized.The optimal operation condition of ultrasonic solvent extraction is:a mixture(15 mL)of pentane:diethyl ether(1:2)was used as the extraction solvent, sonication was held for 20 min,and the number of cycle was three,while the optimal operation condition of subcritical water extraction is:1g tobacco dust mixed with 12g quartz sand,the solvent was acetone-water(90:10,v/v),solvent flush volume,60%of the extraction cell,volume;static extraction time,10 min;number of extraction cycles,3; purge,180 s,using pressurized nitrogen(150 p.s.i.).The reproducibility and recovery rate of simultaneous distillation and extraction,ultrasonic solvent extraction and subcritical water extraction were compared.The results is:for simultaneous distillation,the RSD% were in the range of 4%-10%,except for 2,3-Pentanedione,the recovery rates of other standard samples were in the range of 80%-110%,for ultrasonic solvent extraction,the RSD%were in the range of 1%-10%,the recovery rates of 2,3-Pentanedione,isoamyl alcohol and cyclopentanone were in the range of 60%-80%,the others were in the range of 80%-110%,for subcritical water extraction,the RSD%of volatile substances were poor,the others were not more than 10%,except for 2,3-Pentanedione,isoamyl alcohol, cyclopentanone,and 2-Methyltetrahydrofuran-3-one,the recovery rates of others were in the range of 80%-100%.The method of tobacco chemical components based on GC/FID/MS was developed and applied in the chemical components analysis of two kinds of tobacco leaf group.The key compounds were nicotine,neophytadienean and vitamin E.An analytical method of organochlorine pesticides residuals in tobacco was developed. The tobacco dust was extracted by pressurized liquid extraction,the extracts were purified by SPE,prepared samples were then subjected to GC withμECD and MS detection.The limit of detection of seven standard sample were:α-hexachlorocyolohexane,2.27 ppb;β-hexachlorocyolohexane,2.06 ppb;γ-hexachlorocyolohexane,2.88 ppb;δ-hexachlorocyolohexane,2.15 ppb; PP' DDE,2.55 ppb;PP' DDD,2.54 ppb;PP' DDT,2.32 ppb.