The article addresses the issue of the preservation of biological traces of various origins (saliva, blood, sweat) over time in the context of the application of dactyloscopic methods. It is emphasized that both fingerprint identification and DNA analysis extracted from traces play a key role in forensic investigations. Particular attention is given to the evaluation of the effectiveness and compatibility of various chemical visualization methods for latent fingerprints with subsequent STR profiling. Comparative data are presented on the impact of reagents on the preservation of genetic material, and practical recommendations are discussed for selecting optimal conditions to integrate dactyloscopic and molecular genetic analyses. As a research objective, an analysis was conducted of the qualitative and quantitative characteristics of DNA extracted from biological samples treated with various chemical reagents used in dactyloscopy. The purpose of the research is to determine the optimal time interval after processing during which DNA remains suitable for genetic analysis. The necessity of a comprehensive approach is substantiated, involving the studying of the condition of biological traces before and after chemical treatment, as well as the monitoring of changes over time. The results obtained may contribute to the development of effective methodological approaches for conducting forensic genetic and dactyloscopic expertises, as well as to enhancing the reliability and validity of expert conclusions.