Yan F, McNally R, Kontanis E J, Sadik O A
Department of Chemistry, State University of New York at Binghamton, 13902-6016, USA.
J Forensic Sci. 2001 May;46(3):609-14.
The accurate determination of postmortem interval (PMI) using the formation of adipocere presents a significant challenge to forensic scientists interested in determining the time of death. Several attempts have been made to determine the time since the occurrence of death. However, up to date, this has been difficult because previous approaches have been mainly qualitative, focusing on the later stages of degradation processes. This work presents preliminary results of an experimental model of postmortem adipocere formation using liquid chromatography. Three pig cadavers were submerged in distilled water, chlorinated water, and saline water. Fresh specimens resulting from the degradation in the subcutaneous fat were obtained from the pigs at two-week intervals for a period of ten weeks, and were subjected to chromatographic analysis. By correlating the ratio of the disappearance of hydrolyzed fatty acids with the formation of hydroxystearic and oxostearic acids after death, a simple, quantitative analytical method was developed for the determination of PMI. Experimental observation of the chemistry of adipocere formation indicated that adipocere can be formed only a few hours after an incidence of death and this continues until the saturation of oleic acid degradation after several weeks. Different time courses were obtained for cadavers immersed in distilled, chlorinated, and saline water, respectively. This work has not in any way solved the time since death problem. But it may be an approach to the problem that has not been adequately explored.
利用尸蜡形成准确确定死后间隔时间(PMI),对有志于确定死亡时间的法医科学家而言是一项重大挑战。人们已多次尝试确定死亡发生后的时间。然而,直至目前,这仍颇具难度,因为先前的方法主要是定性的,聚焦于降解过程的后期阶段。这项工作展示了使用液相色谱法进行死后尸蜡形成实验模型的初步结果。将三头猪的尸体分别浸泡在蒸馏水、加氯水和盐水中。每隔两周从猪身上获取因皮下脂肪降解产生的新鲜样本,为期十周,并对其进行色谱分析。通过将水解脂肪酸消失的比率与死后羟基硬脂酸和氧代硬脂酸的形成相关联,开发出一种用于确定PMI的简单定量分析方法。对尸蜡形成化学过程的实验观察表明,死亡后仅数小时即可形成尸蜡,且这种情况会持续至数周后油酸降解达到饱和。分别对浸泡在蒸馏水、加氯水和盐水中的尸体获得了不同的时间进程。这项工作并未以任何方式解决死亡时间问题。但它可能是一个尚未得到充分探索的解决该问题的途径。