Cadd Samuel, Li Bo, Beveridge Peter, O Hare William T, Campbell Andrew, Islam Meez
School of Science and Engineering, Teesside University, Borough Road, Middlesbrough, TS1 3BA, United Kingdom.
Sci Justice. 2016 Jul;56(4):247-55. doi: 10.1016/j.scijus.2015.12.007. Epub 2016 Jan 11.
Bloodstains are often encountered at scenes of violent crime and have significant forensic value for criminal investigations. Blood is one of the most commonly encountered types of biological evidence and is the most commonly observed fingerprint contaminant. Presumptive tests are used to test blood stain and blood stained fingerprints are targeted with chemical enhancement methods, such as acid stains, including Acid Black 1, Acid Violet 17 or Acid Yellow 7. Although these techniques successfully visualise ridge detail, they are destructive, do not confirm the presence of blood and can have a negative impact on DNA sampling. A novel application of visible wavelength hyperspectral imaging (HSI) is used for the non-contact, non-destructive detection and identification of blood stained fingerprints on white tiles both before and after wet chemical enhancement using Acid Black 1. The identification was obtained in a non-contact and non-destructive manner, based on the unique visible absorption spectrum of haemoglobin between 400 and 500nm. Results from the exploration of the selectivity of the setup to detect blood against ten other non-blood protein contaminants are also presented. A direct comparison of the effectiveness of HSI with chemical enhancement using Acid Black 1 on white tiles is also shown.
在暴力犯罪现场经常会发现血迹，其对刑事调查具有重要的法医价值。血液是最常遇到的生物证据类型之一，也是最常见的指纹污染物。推定试验用于检测血迹，而血迹指纹则采用化学增强方法进行处理，如酸性染色剂，包括酸性黑1、酸性紫17或酸性黄7。尽管这些技术成功地显示出了纹路细节，但它们具有破坏性，无法确认血液的存在，并且会对DNA采样产生负面影响。一种新型的可见波长高光谱成像（HSI）应用被用于在使用酸性黑1进行湿化学增强前后，以非接触、非破坏性的方式检测和识别白色瓷砖上的血迹指纹。基于血红蛋白在400至500纳米之间独特的可见吸收光谱，以非接触和非破坏性的方式进行了识别。还展示了该装置针对十种其他非血液蛋白质污染物检测血液的选择性探索结果。同时也展示了HSI与使用酸性黑1对白色瓷砖进行化学增强的效果的直接比较。
