Shaine M L, Premasiri W R, Ingraham H M, Andino R, Lemler P, Brodeur A N, Ziegler L D
Program in Biomedical Forensic Sciences, Boston University School of Medicine, Boston, MA 02118, USA.
Analyst. 2020 Sep 14;145(18):6097-6110. doi: 10.1039/d0an01132k.
An optimized procedure is described for the acquisition of 785 nm excited SERS spectra of dried bloodstains and shown to offer great potential for rapid, portable, highly sensitive and specific, confirmatory identification for forensic applications. Following extraction in 1 μL of 50% acetic acid, a robust, highly reproducible SERS spectrum is observed from dried bloodstains resulting from a hematin-like heme moiety (ferric, high spin). As anticipated, this blood signature can be classified with 100% specificity and sensitivity with respect to the SERS spectra of other body fluids. High quality SERS spectra can be observed from stains of blood diluted by as much as 105. Dried blood spectra acquired on Au and Ag SERS active substrates exhibit very different relative intensities at this electronically, non-resonant excitation wavelength (785 nm) indicating that a strong chemical effect contributes to the SERS enhancement of this body fluid. DFT calculations further confirm the vibrational band assignments of the features seen in these SERS spectra of dried blood.
本文描述了一种优化的程序，用于获取干血斑的785 nm激发表面增强拉曼光谱（SERS），结果表明该程序在法医应用中的快速、便携、高灵敏度和特异性的确认鉴定方面具有巨大潜力。在1 μL 50%乙酸中提取后，从类血红素血红素部分（三价铁，高自旋）产生的干血斑中观察到稳健、高度可重复的SERS光谱。正如预期的那样，相对于其他体液的SERS光谱，这种血液特征可以以100%的特异性和灵敏度进行分类。从稀释高达105倍的血液污渍中可以观察到高质量的SERS光谱。在金和银SERS活性基底上获得的干血光谱在这个非共振激发波长（785 nm）下表现出非常不同的相对强度，这表明强烈的化学效应有助于这种体液的SERS增强。密度泛函理论（DFT）计算进一步证实了这些干血SERS光谱中观察到的特征的振动带归属。
