Comparison Of Blood Latent Fingerprint Fluorescence Developing Methods On Dark Nonporous Surface

The fluorescence developing methods for latent blood handprints has been studied for decades,in this process,researchers invented new reagents,classified the developing principle of fluorescence reagents and improved its developing efficiency for latent blood handprints.However,it is still remain unsolved about the systematic comparison and statistical analysis of their characteristics and application conditions among various fluorescence developing methods.In this study,we systematically compared several fluorescence developing methods,including developing efficiency、showing rate、developing operation and application scope,organized and analyzed their results,summarized their detailed application conditions,in order to provide theoretical reference for practical applications.Here,acid yellow 、 Pyranine and HFB(self-developed)based three kinds of fluorescence developing methods for latent blood handprints were comprehensively studied,and the results turned out that,on same developing surfaces,acid yellow and Pyranine showed higher sensitivity and stronger fluorescence intensity,while HFB had a better resolution and less interference.Meanwhile,the developing effect of latent blood fingerprint on black plastic and black ceramic was better than that on black paint board with higher sensitivity.Secondly,under tested three kinds of fluorescence developing method,the DNA loss can be ignored and DNA extract test were not affected.what’s more,HFB can be applied for potential blood search on the crime scene.Besides,acid yellow and Pyranine shared same latent blood handprints developing principle,whereas HFB possessed its own developing principle and experimental methods.But within 6 months investigation period,all those fluorescence developing methods displayed steady effect.Finally,we concluded four kinds of optimized solutions for cooperation of fluorescence developing method and colored developing methods.How to effectively find and extract latent blood handprints at the crime scene is widely studied,this work comprehensively compared three kinds of fluorescence developing methods for latent blood handprints in dark non-porous surfaces,and provided more systematic and valuable reference for the actual scene of a crime.