SPME/GC联用测定芥末油中辛辣物质异硫氰酸烯丙酯的研究

Study on SPME-GC Determination of Allyl Isothiocyanate in Mustard Oil

研究使用顶空固相微萃取 (SPME)技术与气相色谱 (GC)联用测定芥末油中辛辣物质异硫氰酸烯丙酯。采用正交设计研究了萃取温度、搅拌速度、萃取时间、解吸时间四因素四水平对萃取效率的影响 ,结果表明 ,影响萃取效率的主次因素依次为萃取温度、搅拌程度、萃取时间、解吸时间 ;以萃取温度 4 0℃、搅拌程度 90 0r/min、萃取时间30min、解吸时间 5min为最理想。该方法在含异硫氰酸烯丙酯 0 .0 2 μL/L～ 0 .6 0 μL/L范围内线性良好 ,相关系数r=0 .996 4;对芥末油中加标异硫氰酸烯丙酯 0 .10 μL/L、0 .2 0 μL/L、0 .30 μL/L ,回收率分别为 91.18%、94 .36 %、10 6 .4 % ,相对标准偏差分别为 2 .32 %、1.99%和 4 .2 7% ;最小检出限为 0 .0 0 5 6 μL/L。

A method for simultaneous determination of a pungent substance, allyl isothiocyanate(AITC), in mustard oil sample was studied using headspace solid-phase microextraction (SPME) and gas chromatography(GC). Orthogonal design of 4 factors at 4 levels was applied for the optimization of Headspace system parameters: extraction temperature, stir speed, extraction time, and desorption time, which were set at 40℃, 900r/min, 30min, 5min, respectively. The results showed that extraction temperature and stir speed were main factors influencing extraction efficiency, and extraction temperature had greater influence on AITC. Under the optimum conditions, linear limits of the method were in the range 0.02μL/L～0.60μL/L(r=0.9964),the recoveries were in the range 91.18%～1.064%,And relative standard deviation(RSD) of the method was 1.99%～4.27%,limit of detection was 0.0056μL/L.