Dataset for: Surface-enhanced Raman spectroscopy hair analysis after household contamination

Trace evidence found at crime scenes is rarely in an unsullied condition. Surface-enhanced Raman spectroscopy (SERS) is a modern analytical technique that can be used for the detection of artificial hair colourants (S. Higgins and D. Kurouski, Surface-Enhanced Raman Spectroscopy Enables Highly Accurate Identification of Different Brands, Types and Colors of Hair Dyes, Talanta, 2022, 251, 123762). However, contaminants pose a problem to collecting accurate spectra from the dyes. In this study, we sought to analyze how the different physical properties of contaminants can influence the collected spectra. We utilized 11 household substances of varying viscosity and opacity to contaminate hair dyed with permanent black or semi-permanent blue dyes. We discovered that contaminant opacity generally does not affect the spectral quality but that high contaminant viscosity does and that acidic substances could destroy the colourant's spectral identity altogether. Cleaning the contaminated hair with a water rinse allowed the underlying colourant to be identified in 21 out of 22 cases. Overall, this study provided a clearer understanding of the capabilities and limitations of SERS in forensic hair analysis.犯罪现场发现的微量物证极少处于纯净无污的状态。表面增强拉曼光谱（Surface-enhanced Raman spectroscopy, SERS）是一种现代分析技术，可用于检测人工染发色素（S. Higgins与D. Kurouski，《表面增强拉曼光谱可高精度识别不同品牌、类型及颜色的染发剂》，《Talanta》，2022年，第251卷，123762号）。然而，污染物会干扰从染发剂中获取精准光谱的过程。本研究旨在探究污染物的不同物理性质如何对采集到的光谱产生影响。我们选取11种黏度、不透明度各不相同的家用物质，对使用永久性黑色染发剂或半永久性蓝色染发剂染色的发丝进行污染处理。研究发现，污染物的不透明度通常不会对光谱质量造成影响，但高黏度污染物会产生此类影响，且酸性物质可完全破坏染发色素的光谱特征。使用清水冲洗受污染的发丝后，22组样本中有21组可成功识别出基底染发剂的光谱特征。综上，本研究进一步明确了表面增强拉曼光谱在法医毛发分析中的应用能力与局限性。