Characterization of postmortem biochemical changes in rabbit plasma using ATR-FTIR combined with chemometrics: A preliminary study
Characterization of postmortem biochemical changes in rabbit plasma using ATR-FTIR combined with chemometrics: A preliminary study
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使用 ATR-FTIR 结合化学计量学表征兔血浆死后生化变化：初步研究
DOI：
10.1016/j.saa.2016.10.041
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
Wang ZY
中科院分区：
文献类型：
--
作者：
Zhang Ji;Li Bing;Wang Qi;Li Chengzhi;Zhang Yinming;Lin Hancheng;Wang Zhenyuan;Wang ZY
由于缺乏准确可靠的方法，死亡时间的确定一直是法医学中最具挑战性的工作之一。对于后期PMI的确定尤其困难。虽然已经进行了许多基于化学方法的各种类型的体液的尝试来解决这个问题，但是很少有研究集中在血液样本上。在这项研究中，我们采用了衰减全反射（ATR）-傅里叶变换红外（FTIR）技术，结合主成分分析（PCA），以监测生化变化，在兔血浆中增加PMI。采用偏最小二乘（PLS）模型对独立样本集的光谱数据进行PMI预测。我们的研究结果表明，死后血浆成分的化学变化是时间依赖性的，各种成分，包括蛋白质，脂质和核酸有助于区分样品在不同的时间点。结果表明，组合PLS模型能较好地预测死亡后48 h内的PMI，预测值与实际值的拟合度为0.984，误差为± 1.92 h。鉴于ATR-FTIR技术的简单性和可移植性，本研究为该技术在法医学中的应用提供了实验和理论依据。(C)2016爱思唯尔B. V.保留所有权利。
Postmortem interval (PMI) determination is one of the most challenging tasks in forensic medicine due to a lack of accurate and reliable methods. It is especially difficult for late PMI determination. Although many attempts with various types of body fluids based on chemical methods have been made to solve this problem, few investigations are focused on blood samples. In this study, we employed an attenuated total reflection (ATR)-Fourier transform infrared (FTIR) technique coupled with principle component analysis (PCA) to monitor biochemical changes in rabbit plasma with increasing PMI. Partial least square (PLS) model was used based on the spectral data for PMI prediction in an independent sample set. Our results revealed that postmortem chemical changes in compositions of the plasma were time-dependent, and various components including proteins, lipids and nucleic acids contributed to the discrimination of the samples at different time points. A satisfactory prediction within 48 h postmortem was performed by the combined PLS model with a good fitting between actual and predicted PMI of 0.984 and with an error of +/- 1.92 h. In consideration of the simplicity and portability of ATR-FTIR, our preliminary study provides an experimental and theoretical basis for application of this technique in forensic practice. (C) 2016 Elsevier B.V. All rights reserved.