固相微萃取-气相色谱-质谱联用快速鉴别香米真伪

Rapid identification of aroma rice by solid phase micro-extraction gas chromatography-mass spectrometry

目的建立固相微萃取-气相色谱-质谱(SPME-GC-MS)快速测定香米香味特征化合物2-乙酰基吡咯啉的方法,以用于鉴别香米的真伪。方法香米样品经粉碎后,加入内标物2,4,6-三甲基吡啶,密封,在80℃炉温箱中经固相微萃取(萃取纤维头为50/30μm DVB/Carboxen/PDMS)提取40 min,提取物经毛细管色谱柱分离,全扫描监测气质联用法测定香米香味特征物质。结果该方法在短时间内可以分析香米特征物质2-乙酰基吡咯啉,且检出限和重复性好,方法检出限为0.001 mg/kg,6针峰面积比的相对标准偏差为6.54%。结论该方法处理简单、快速、样本和试剂消耗少,尤其适合香米的快速定性测定及真伪鉴别。

Objective To develop a gas chromatography-mass spectrometry（GC-MS） method with solid phase micro-extraction（SPME） to detect the characteristic compound 2-acetyl-l-pyrroline（2-AP） in aroma rice.Method The internal standard of 2,4,6-trimethylpyridine was added into aroma rice after crushed.The sample was extracted by SPME under sealed condition at 80 ℃ oven for 40 min,and then analyzed by gas chromatography using Rxi-5 MS capillary column（30 m×0.25 mm×0.25 μm） for separation and mass spectrometry in scan monitoring mode for detection.Results This method could detect the characteristic compound in aroma rice with good repeatability and sensibility.The detection limit of this method was 0.001 mg/kg,and the relative standard deviation was 6.54%（n=6）.Conclusion The proposed method is simple,rapid,and sensitive with less reagent consumption,which is suitable for rapid qualitative analysis and identification of aroma rice.