深色物体表面血手印的CdSe量子点标记荧光显像

CdSe Quantum Dots Labeling to Blood Fingerprints on Dark Surfaces and Fluorescent Imaging

合成了巯基乙酸修饰的CdSe量子点溶液,用荧光光谱法对该材料进行荧光测试,结果表明,该纳米材料在365 nm激发波长下具有优异的荧光性能。用CdSe量子点水溶液对多种深色物体表面上的血手印进行标记并通过CCD相机获取荧光图像。考察标记时间、血液浓度、遗留时间与血手印显像清晰度的关系。结果表明,标记时间为30 min就可以得到理想的荧光图像。该材料应用范围较为广泛,对常见深色物体上的血手印有较好的标记荧光成像效果,灵敏度可以达到1%血浓度。CdSe量子点标记血手印操作简单,适用范围广,荧光亮度高,与背景形成的反差大,获得的荧光图像手印纹线清晰、流畅。

Water-soluble fluorescent CdSe quantum dots（QDs） were synthesized using thiolglycolic acid（TGA） as the stabilizer and characterized by fluorescence spectroscopy.The material exhibited strong visible fluorescence under excitation at 365 nm.QDs were applied to label blood fingerprints deposited on non-porous surfaces.Then fluorescent images of fingerprints were obtained by the charge-coupled device（CCD） camera.The effects of labeling time,blood concentration and stored time of blood fingerprints on imaging were investigated.The results showed that the fluorescent images could be obtained within labeling time of 30 min.CdSe QDs can detect blood fingerprints on different surfaces especially on black surface;1% diluted blood fingerprints also could be labeled.The labeled blood fingerprints have higher and stable fluorescence intensity,weaker background interference and better contrast between fingerprints and substrate.CdSe QDs are promising reagents for blood fingerprints development on non-porous dark surfaces.