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1.
用液相色谱/大气压化学电离离子阱质谱建立了一种分析烟草中游离茄尼醇的方法。烟草样品用甲醇振荡提取30 min,在分析前无需进行其它前处理。在1.8μm快速分离C18色谱短柱上用V(甲醇)∶V(异丙醇)=85∶15等梯度洗脱实现了茄尼醇的快速分离。用不带碰撞能量的二级质谱全扫描选择监测离子m/z 613.6进行定量,检出限为0.4μg/L,RSD为1.1%,两种添加量的回收率分别为97%和99%。方法应用于不同烟草和烟草制品样品的检测分析。  相似文献   
2.
采用高效液相色谱法对我国东北地区茄科植物废弃物马铃薯、茄子、番茄和辣椒的叶片中茄尼醇进行了定性和定量分析。结果表明:马铃薯和茄子的叶片中茄尼醇质量分数较高,分别可达到0.331%和0.207%;番茄和辣椒的叶片中茄尼醇的质量分数分别为0.092%和0.089%。方法的线性范围为0.61~6.10μg,回收率为99.5%~103.3%。  相似文献   
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4.
薄层分离-库仑滴定法测定茄尼醇   总被引:17,自引:0,他引:17  
提出以2mol/LKBr-醋酸(1:3V/V)为电液,在阳极电生溴与尼醇发生反应来测定茄尼醇含量的库仑滴定法。茄尼醇与溴反应,其n值为18,对于烟叶以物中茄尼醇,以正己烷-二氯乙烷-丙醇为展开剂,用薄层色地邓以分离,用库仑滴定法进行测定 。  相似文献   
5.
建立了高效液相色谱法测定电子烟烟液及气溶胶中茄尼醇的含量。电子烟气溶胶中的茄尼醇使用剑桥滤片捕集,烟液及滤片分别经甲醇振荡萃取后,直接进行高效液相色谱测定。结果表明:茄尼醇在0.016~8.11μg/mL浓度范围内线性关系良好(R2=0.9993),烟液及气溶胶在3个加标水平的回收率在97.06%~104.39%之间,相对标准偏差不高于1.06%,检出限为0.010μg/g。实际样品测试表明:电子烟烟液中的茄尼醇含量在0.014~25.67μg/g,检出率为64.21%;在一定的抽吸模式下,对于茄尼醇含量为25.67μg/g的烟液,8种电子烟产品抽吸150口的气溶胶茄尼醇释放量为2.62~10.12μg。  相似文献   
6.
HPLC coupled online with atmospheric pressure chemical ionization MS (APCI-MS) technique was evaluated for the qualitative and quantitative determination of solanesol in extracts of tobacco leaves. The solanesol and other compounds in the extract were separated on an Alltima C(8) (4.6 mm x 250 mm) column with methanol and water (98:2 v/v) as mobile phase, with flow rate of 0.8 mL/min and UV detection wavelength of 211 nm. In the APCI(+) mode, abundant stable [M-H(2)O + H](+) ion (m/z at 613.5) was observed, with low abundance of other fragmentation ions. A comparison of APCI-MS and ESI-MS techniques showed that APCI mode is more sensitive than ESI mode, and thus better suited for solanesol analysis. When comparing UV 211 nm and APCI-MS in SIM for solanesol quantification, the former offered better precision and reproducibility, but the latter was more than 200 times sensitive in detection. The developed method has been successfully applied to the analysis and comparison of solanesol concentration in different tobacco leaf samples.  相似文献   
7.
A direct and simple method for analyzing solanesyl esters found in tobacco leaves was developed. Sample preparation was performed by accelerated solvent extractor 200 (ASE200™) using n-hexane followed by evaporating solution in vacuo and dissolving residue with acetone. The separation of analytes was conducted through high-performance liquid chromatography (HPLC) equipped with an SIL-C18/5C™ column and the non-aqueous reversed phase chromatography (NARP) technique using acetone and acetonitrile as the mobile phase with a linear gradient. Atmospheric pressure chemical ionization/mass spectrometer (APCI/MS) in positive mode was used to detect solanesyl esters in the following conditions: capillary voltage 4000 V, corona current 10 μA, drying gas flow 5 mL/min, fragmentor voltage 200 V, nebulizer pressure 60 psi, and vaporizer temperature 500 °C. Each solanesyl ester was identified by the comparison of analyte with synthesized solanesyl esters. Quantification was conducted by selected ion monitoring (SIM) mode in order to detect the specific product ion (613.6 m/z) fragmented from solanesyl ester. The calibration curve was made in the range of 0.1–40 μg/mL with a regression coefficient over 0.999 on almost all solanesyl esters. The limit of detection (LOD) and limit of quantification (LOQ) ranged from 0.01 to 0.05 μg/mL and from 0.03 to 0.15 μg/mL, respectively, on the SIM mode of MS for quantification. Recovery (%) ranged from about 80 to 120%. The direct quantification using the developed method succeeded in showing a different amount and composition of solanesyl esters among various tobacco leaves.  相似文献   
8.
烟草各部位中茄尼醇含量分布研究   总被引:1,自引:0,他引:1  
采用Kromsil ODS-1色谱柱,V(甲醇)∶V(乙醇)=55∶45混合液为流动相,在紫外检测波长设定为211 nm的高效液相色谱条件下测定了烟草中各部位提取物中的茄尼醇,其中烟叶中茄尼醇的质量分数为0.45%,其他部位茄尼醇的质量分数为:烟梗0.037%,烟茎0.0037%,烟根0.0037%,其中烟叶中的茄尼醇量最高,具有提取价值.  相似文献   
9.
The method of solid-phase extraction (SPE) for the concentration and clean-up of tobacco extract samples during solanesol analysis was proposed in this work. A column (200 mm × 4 mm i.d.) packed with 0.10 g silica gel (with particle size of 70 μm, porosity of 0.5 and surface area of 400 m2 g−1) was used as SPE cartridge. Several extraction parameters, such as sample loading flow (0.3–7 mL min−1), sample volume (5–50 mL), the column adsorption capacity and elution were evaluated to provide a fast, quantitative and reproducible SPE method. A mean solanesol recovery was 97.5 ± 1.6% (mean ± sd) and mean intra- and inter-day reproducibility was higher than 97%. It can be used in the analysis of solanesol in tobacco extracts.  相似文献   
10.
库仑滴定法测定烟叶提取物中茄尼醇   总被引:16,自引:0,他引:16  
本文提出用库仑滴定法测定茄尼醇。以含有1mol·L-1KBr的78%(V/V)醋酸溶液为介质,以5mA恒电流为电解电流,对布尼醇进行库仑滴定,用双铂电极电流法指示滴定终点,得到满意结果.方法简便、准确,不需要标准溶液,不需要昂贵仪器。  相似文献   
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