铬黑T显现潜血手印最优条件探讨

Study on the Optimal Condition of Developing Latent Blood Fingermarks by Chromium Black T

目的以铬黑T为溶质,不同溶液为溶剂制备新型显现液,确定铬黑T溶液显现潜血手印的最佳配方及使用范围。方法通过考察甲醇、二氯甲烷、丙酮、乙酸乙酯、无水乙醇、蒸馏水六种溶剂、不同的显现液浓度、潜血手印遗留时间、承痕体种类以及血液浓度等因素对显现效果的影响,建立最佳显现液体系并与传统染色法进行对比。结果0.020 mol/L的铬黑T-甲醇溶液显现效果最佳,采用浸泡法、滴显法、喷显法均能清晰显现皮革、玻璃片、瓷砖、红色塑料片、农夫山泉红色珠光膜上的潜血手印。与传统染色试剂氨基黑10B对比,铬黑T-甲醇显现液在显现稀释后的血液和陈旧潜血手印时效果更佳。结论0.020 mol/L的铬黑T-甲醇溶液为最佳显现配方,该方法显现效果好、适用范围较广、配合装置使用易于携带且无需后置处理,可供公安现场办案使用,具有较高的应用价值和应用前景。

Objective With Chromium black T as solute and various reagents as solvents,different solutions were prepared and studied to find out the best formula and application range of chromium black T solution for developing blood fingermarks.Methods By investigating the effects of different reagents(methanol,dichloromethane,acetone,ethyl acetate,anhydrous ethanol,and distilled water),the concentration of Chromium black T,residual time,stain bearing object and blood concentration,the solution that produced the best developing effect was selected,and compared with the traditional staining method.Results The development effect of 0.020 mol/L Chromium black T-methanol solution was the best,and the fresh blood fingermarks on glass,ceramic tile and plastic sheet can be clearly displayed by immersion,drop and spray method.Besides,compared with the traditional staining reagent Amino black 10B,Chromium black T-methanol solution had obvious advantages in developing latent fingermarks of diluted blood and old blood.Conclusion The optimized formula for developing latent blood fingermarks was 0.020 mol/L Chromium black T-methanol solution.The proposed solution has good developing effect and wide application range.It is portable and easy to use with the coordination device without post-processing,thus it can be used in site by public security organs.It has high application value and prospect.