加速溶剂萃取-气相色谱-串联质谱法测定烟丝中5种羧酸苯乙酯的含量及对烟丝加香的均匀性评价

Determination of 5 Phenyl Ethyl Carboxylates in Cut Tobacco by GC-MS/MS with Accelerated Solvent Extraction and Evaluation on Uniformity Evalution of the Aromatizing Process

将烟丝样品置于温度(20±1)℃及相对湿度(60±3)%条件下平衡24h。称取此样品4.0g置于Dionex ASE 350萃取仪的34 mL萃取池中,用正己烷作为溶剂进行加速溶剂萃取(ASE)。加速萃取的温度为100℃,静态萃取时间为5min,循环次数为2次。于萃取液中加入乙酸苯甲酯内标(100mg·L^-1)溶液0.50mL,混匀后经0.45μm滤膜过滤,取滤液进行气相色谱-串联质谱法分析。采用HP-5MS毛细管色谱柱(30m×0.25mm,0.25μm),在60~280℃温度区间程序升温模式分离后,按电子轰击离子源和多反应监测模式条件进行串联质谱测定。所测定的5种羧酸苯乙酯的质量浓度均在0.10~10.00mg·L^-1内与其对应的峰面积之间呈线性关系,其检出限(3S/N)均为0.01mg·L^-1。按标准加入法测定了方法的回收率,结果为91.0%~107%,测定值的相对标准偏差(n=6)均小于10%。同一批次内和不同批次间外加标记物的变异系数(CVi)分别为5.8%~8.8%和6.3%~8.4%,说明加香工序的均匀性良好。

Cut tobacco sample was equilibrated for 24 hunder the condition of(20±1)℃ and relative humidity of(60±3)%.A portion(4.0 g)of the equilibrated sample was taken and transferred to the 34 mL of extraction cell of the Dionex ASE 350 extractor and submitted to ASE with n-hexane.In ASE process,conditions of temperature(100℃),static extraction time(5 min),and cycling frequency(2 times)were adopted.The extract was separated and 0.50 mL of 100 mg·L^-1 phenylmethyl acetate solution was added as internal standard.After well mixing and filtration through 0.45μm filtering membrane,the filtrate was used for GC-MS/MS analysis.Chromatographic separation was carried out on HP-5 MS capillary column(30 m×0.25 mm,0.25μm)and under the mode of programmed temperature elevation ranged from 60℃to 280℃.EI and MRM mode were used in MS/MS determination.Linearily ranges of standard curves of the 5 phenylethyl carboxylates determined were found same between 0.10 mg·L^-1 and 10.00 mg·L^-1,and their detection limits(3 S/N)were found having the same value of 0.01 mg·L^-1.Recovery was tested by standard addition method,and the results of recovery were found in the range of 91.0%-107%,and values of RSDs(n=6)were found all less than 10%.Uniformity of aromatizing process for the cut tobacco were tested on samples taken from intra and inter production batches of the aromatizing process,giving values of coefficients of variation(CVi)in the ranges of 5.8%-8.8% and 6.3%-8.4%,respectively,showing that the uniformity of aromatizing was good and satifactory.