犯罪现场微量油脂物证酸败老化特征分析

Analysis of Oxidative Rancidity Characteristics of the Trace Oil in Crime Scene

系统研究微量油脂物证在不同载体和不同老化因素下检验的可行性和液相色谱图的特征,得出不同老化因素对油脂识别的影响。采用高效液相色谱蒸发光检测法更适合分析不同载体上老化后的微量油脂物证。动植物油脂老化特征峰的保留时间短,能够与识别油脂种属的主色谱峰区分,其氧化酸败受温度、湿度、光照条件、载体性质等因素的协同作用,影响顺序从强至弱依次为紫外灯照射、干燥条件下红外加热、户外阳光直射、高湿度下红外加热。详细分析不同老化因素下的老化峰的特征,为犯罪现场动植物油脂物证的正确提取、保存和识别检验提供依据。

The feasibility and the characteristics of the liquid chromatogram of trace oil and fat evidence in different carriers and different aging factors were studied systematically,and the influence of different aging factors on the trace oil was found.The HPLC evaporative light detection method is more suitable for the analysis of aging oil trace evidence on different carriers.The retention time of animal and vegetable oils and fats is short,and it can be distinguished from the main chromatographic peaks of identifying oil species,the oxidative rancidity was influenced synergistically by the oxidation temperature,humidity,illumination conditions,and nature of the carrier.The order of influence from strong to weak is ultraviolet light,the infrared heating under drying,outdoor sunlight,infrared heating under high humidity.The characteristics of the aging peak under different aging factors are analyzed in detail,which provides the basis for the correct extraction,preservation and identification of the evidence of animal and vegetable oils in crime scene.