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.

中文翻译：

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表面增强的拉曼散射，可对干燥的血迹进行可靠，灵敏的检测和确认性鉴定。

描述了一种优化程序，用于采集干燥血迹的785 nm激发SERS光谱，并显示出为快速，便携式，高度灵敏和特异的鉴定性鉴定提供巨大潜力，可用于法医学应用。用1μL50％乙酸萃取后，从血红素样血红素部分（铁，高自旋）产生的干燥血迹中观察到了稳定，高度可重复的SERS光谱。如预期的那样，可以相对于其他体液的SERS光谱以100％的特异性和敏感性对这种血液特征进行分类。从稀释多达10 ⁵的血液污渍中可以观察到高质量的SERS光谱。在Au和Ag SERS活性底物上获得的干血谱在此电子非共振激发波长（785 nm）下表现出非常不同的相对强度，表明强大的化学作用有助于增强这种体液的SERS。DFT计算进一步证实了这些干血SERS光谱中所见特征的振动带分配。