Centre for Forensic Science, University of Technology, Sydney, Broadway, NSW 2007, Australia.
Forensic Sci Int. 2012 Jun 10;219(1-3):208-14. doi: 10.1016/j.forsciint.2012.01.006. Epub 2012 Jan 30.
Conventional fingermark powders rely on contrast induced by absorption/reflection (e.g. black powder) or luminescence in the visible region (e.g. Blitz Green(®)). In most cases, these powders provide sufficient contrast; however, in some circumstances surface characteristics can interfere with the visualisation of powdered fingermarks. Visualisation in the near infra-red (NIR) region, however, has been shown to eliminate interferences commonly encountered in the visible region. In this study, a mixture of rhodamine 6G and the NIR laser dye styryl 11 (STaR 11) was coated onto an aluminium oxide nanopowder and then mixed with silver magnetic powder to develop and visualise fingermarks in the NIR. When compared to Blitz Green(®), it was determined that the STaR 11 magnetic powder was better suited for marks deposited on textured surfaces and for older marks, whereas Blitz Green(®) performed better on smooth glossy surfaces. The ability of the STaR 11 mixed dye formulation to be visualised in both the visible and NIR regions also provides a significant advantage over conventional luminescent fingermark powders.
传统的指印粉末依赖于吸收/反射引起的对比度（例如黑色粉末）或可见区域的发光（例如 Blitz Green(®)）。在大多数情况下，这些粉末提供了足够的对比度；然而，在某些情况下，表面特性会干扰粉末指印的可视化。近红外（NIR）区域的可视化已被证明可以消除可见区域中常见的干扰。在这项研究中，将罗丹明 6G 和近红外激光染料 styryl 11（STaR 11）的混合物涂覆在氧化铝纳米粉末上，然后与银磁性粉末混合，以在 NIR 中开发和可视化指印。与 Blitz Green(®)相比，确定 STaR 11 磁性粉末更适合沉积在纹理表面和较旧的标记上，而 Blitz Green(®)在光滑有光泽的表面上表现更好。STaR 11 混合染料配方在可见和 NIR 区域都能被可视化的能力也为传统的发光指印粉末提供了显著的优势。
