A systematic review on the analysis of trace materials via Raman spectroscopy: Advancements and forensic implications

Raman spectroscopy, complemented by advanced techniques such as surface-enhanced Raman spectroscopy (SERS) and micro-Raman spectroscopy, is increasingly expanding its forensic applications in analysing trace materials. Forensic practitioners are adopting it more widely due to its simplicity, speed, non-destructive nature, and minimal or no sample preparation required. Despite certain limitations, such as relatively low sensitivity and significant fluorescence interference, Raman spectroscopy has been greatly enhanced by advanced techniques like SERS and Resonance Raman Spectroscopy, which effectively mitigate these issues and help unlock the full potential of Raman analysis. This review compiles extensive data from three major databases-Web of Science, Scopus, and Google Scholar-to demonstrate the utility of Raman spectroscopic techniques in the forensic analysis of trace samples, particularly in the examination of inks, dyes, gunshot residues, paints, and related substances. The study shows that Raman spectroscopy has significantly simplified the analysis of forensic traces, offering a promising approach for the on-site examination of a wide range of traces with improved efficiency and accuracy.