摘要：采用不同浓度的茚三酮水溶液、茚三酮丙酮溶液显现复印纸上不同种类手印，探究不同手印物质在两种配方下的最适浓度。采用茚三酮水溶液通过喷雾方式探究热敏纸上不同种类手印的最适浓度。实验结果表明，2%茚三酮水溶液可使复印纸上的血指印、蛋清指印、唾液指印、汗潜指印、皮脂指印清晰显现，1%茚三酮水溶液可清晰显现蛋黄手印；1%茚三酮丙酮溶液即可使复印纸上不同种类手印显现出清晰完整的乳突纹线；热敏纸2%茚三酮水溶液可使不同种类手印满足鉴定要求。

Abstract: Different concentrations of ninhydrin aqueous solution and ninhydrin acetone solution were used to visualize different types of fingerprints on copy paper, and to explore the optimum concentrations of different fingerprint substances under the two formulations. The optimal concentration of different fingerprint compositions on thermal paper was investigated by spraying with ninhydrin aqueous solution. The experimental results show that 2% inhydrin aqueous solution can clearly develop blood fingerprints, egg white fingerprints, saliva fingerprints, sweat latent fingerprints, and sebum fingerprints on copy paper; 1% ninhydrin aqueous solution can clearly develop egg yolk fingerprints; 1% ninhydrin acetone solution can make different fingerprint substances on copy paper show clear and complete papilla lines; 2% ninhydrin water solution can make different fingerprint substances on the the thermal paper meet the identification requirements.

Key Words: Ninhydrin; Fingerprint substances; Fingerprint development; Optimum concentration