紫胶红色素增强血手印的实验研究OA

Fingerprints are a crucial form of forensic evidence at crime scenes.Blood fingerprints,as a type of fingerprint trace,possess significant forensic value for identification via DNA analysis and fingerprint pattern matching.This study discussed the enhancement effects of lac dye on bloody fingerprints.In the experiments,a solution with 0.25％ lac dye and a 5％acetic acid(pH2.55)was applied to enhance the bloody fingerprints on 12 common substrates,as well as aged bloody fingerprints with different drying time and bloodstain concentrations.The enhancement effects were compared.The results demonstrate that lac dye has practical value in enhancing blood fingerprint,with good enhancement effects and high sensitivity on most non-porous substrates,and it is also suitable for enhancing old and low-concentration bloody fingerprints.However,its performance on porous substrates is relatively moderate.This dye solution is simple to prepare,easy to operate,and convenient to store,making it suitable for the visualization and extraction of bloody fingerprints during criminal scene examinations.