Silver-assisted development and imaging of fingermarks on non-porous and porous surfaces

In order to deal with the range of surfaces encountered in crime scenes and items associated with crimes, forensic fingermark examiners must have access to a range of latent mark enhancement techniques, each compatible with a particular type of surface. Consequently, the development of techniques with universal or even wide-ranging surface compatibility would be valuable to law enforcement. Herein, we describe a one-step silver sputtering method for the enhancement of latent fingermarks on plastic, glass, paper and metal substrates. This method allows for the ridge pattern to be captured for human identification purposes and, more importantly, for the downstream mass spectrometric imaging of the fingermark in order to display the spatial distribution of common endogenous and exogenous substances such as illicit drugs