Lipophilic magnetic nanocomposite of Fe3O4@SiO2@Me for efficient visualization of latent fingerprints on various surfaces

This study intends to design and prepare a new magnetic nanopowder as a quasi-chemical dusting agent for the development of latent fingerprints (LFPs) on various surfaces. Tuning of the nanopowder properties between chemical and physical fingerprint agents was performed by investigation of surface lipophilicity influence on the visualization of latent fingerprints. For this purpose, trimethoxymethylsilane (TMMS) was used to modify Fe 3 O 4 @SiO 2 core–shell magnetic nanoparticles to obtain a lipophilic, selective, and efficient magnetic nanopowder for detecting LFPs. Various analytical techniques were used to characterize the nanoparticles to show that the achieved structures and properties are well-suited for forensic science. Finally, fingerprints developed using the Fe 3 O 4 @SiO 2 @Me nanopowder were applied on several porous and nonporous surfaces. The Fe 3 O 4 @SiO 2 @Me new lipophilic fingerprint nanopowder offers simple synthesis process, convenient use for routine casework and low price. Graphical abstract