Vibrational spectroscopic approaches for semen analysis in forensic investigation: State of the art and way forward

Semen is one of the most important body fluids encountered in sexual assaults. Traditional chemical tests are being performed for several decades for analysis of this fluid. Recent advancements in the field of forensic evidence analysis are gradually overcoming the limitations of the existing techniques. Vibrational spectroscopy, which includes IR absorption and Raman scattering, offers promising instrumentation to obtain adequate information from a sample without altering its chemical profile. It is robust, non-destructive, rapid, cost-effective, sensitive, and specific to the samples. The last decade saw a rapid upsurge in semen analysis by vibrational spectroscopy around the globe. The studies ranged from the identification and discrimination of semen from other body fluids to the estimation of time since deposition. Despite the investigations on the effect of multiple factors e.g., substrates, mixed fluid samples, disorders, etc. on the analysis of semen, the instrumentation still not achieved the optimum level for its practical implementation in real crime scenarios. The present review discussed the current available forensically relevant studies for semen analysis by vibrational spectroscopy and emphasizes the existing limitations and future possibilities.

Automated summary

Semen is a critical body fluid in sexual assaults, and vibrational spectroscopy has emerged as a valuable tool for its analysis, but practical limitations still exist. Research has focused on identifying, discriminating, and estimating timing since deposition of semen.