Effect of Temperature on Development of Latent Fingerprint by Ninhydrin Method

Abstract

This paper discusses the importance of fingerprints in forensic investigations, categorizing them into three types: latent, patent, and plastic. Latent fingerprints, which are invisible and composed of sweat and oil, require specific methods for development, with the Ninhydrin method being the most common for porous surfaces. The Ninhydrin method, first utilized in 1959, involves a chemical reaction between ninhydrin and alpha-amino acids in proteins, resulting in a colored compound that reveals the fingerprints. While effective, the method has drawbacks, including its carcinogenic nature and the need for humidity for optimal development. The study investigates how temperature affects the development time of latent fingerprints using the Ninhydrin method. Various surfaces, including plain paper, bond paper, cheques, and currency notes, were tested at different temperatures. Results indicated that higher temperatures significantly reduced the time required for fingerprint development, demonstrating a beneficial impact of temperature on the process. Overall, the findings suggest that optimizing temperature can enhance the effectiveness of the Ninhydrin method in forensic applications, leading to quicker and clearer fingerprint development.