B&W Tek Raman Solution Suite for Forensics Applications

Significance of the Topic

Raman spectroscopy offers forensic investigators a rapid, non-destructive approach for identifying a vast array of materials encountered at crime scenes and in laboratory settings. Its high chemical specificity and minimal sample preparation make it well suited for field deployment as well as controlled laboratory analysis.

Classified as a Category A analytical method by SWGDRUG, Raman techniques enable law enforcement, crime scene technicians and forensic analysts to detect and distinguish controlled substances, explosives residues, chemical precursors and other trace evidence without compromising sample integrity.

Objectives and Study Overview

This application note presents B&W Tek’s Raman Solution Suite tailored to forensic workflows. It describes handheld and portable instruments, along with specialized accessories, that collectively address common challenges in narcotics screening, explosive detection, mixture analysis and identification of dark or fluorescent samples.

The aim is to demonstrate how these systems deliver laboratory-grade performance in diverse operational scenarios, from roadside interdiction to detailed laboratory characterization.

Methodology

• Fundamentals: Raman spectroscopy probes vibrational modes of molecular bonds, producing characteristic spectra that serve as fingerprints for compound identification.
• Excitation Sources: Standard systems employ a 785 nm laser for optimal balance of sensitivity and fluorescence suppression. A 1064 nm excitation option further reduces fluorescence from colored or pigmented samples.
• Sample Formats: Solid powders, liquids, fibers, slurries and packaged substances can be analyzed directly or via minimal preparation.
• Mixture Analysis: Advanced algorithms deconvolve overlapping spectra to identify major components in multi-constituent samples.
• Trace Detection: Surface-enhanced Raman spectroscopy (SERS) using nanoparticle substrates amplifies signals of low-concentration analytes for ultra-sensitive screening.

Instrumentation Used

• TacticID Handheld Raman Analyzer: Field-deployable, non-contact screening with built-in library matching and automated reporting; available with 785 nm or 1064 nm lasers.
• i-Raman EX Portable Raman System: 1064 nm excitation coupled to a cooled InGaAs detector, enabling high S/N measurements of dark or fluorescent samples; supports fiber optic probes.
• TacPac™ SERS Adapter: Facilitates trace-level detection by applying dissolved samples to a SERS substrate for enhanced sensitivity.
• Raman Video Microscope Accessory: Precisely aligns laser and sample under microscopic guidance for targeted analysis of heterogeneous specimens.

Main Results and Discussion

• Dark and Fluorescent Samples: The 1064 nm systems successfully suppress autofluorescence, enabling clear identification of street heroin and heavily cut narcotics that often confound 785 nm instruments.
• Mixture Deconvolution: Handheld mixture analysis reliably detects active ingredients and cutting agents in complex powders without sample destruction.
• Trace Analysis: SERS workflows identify low-dose APIs and controlled substances, providing a powerful tool against counterfeit pharmaceuticals.
• Field-to-Lab Consistency: Data from handheld TacticID units align with laboratory measurements on the i-Raman EX, supporting chain-of-custody and prosecutorial requirements.

Benefits and Practical Applications

• Rapid Screening in Original Packaging: Non-invasive analysis through plastic bags or glass containers reduces evidence handling and cross-contamination.
• Automated Reporting and Audit Trail: Time/date stamps, self-diagnostics and secure data transfer facilitate compliance with forensic QA/QC standards.
• Versatility: One platform addresses drugs, explosives, hazardous chemicals and biological samples using the same spectral libraries.
• Cost-Effective Microanalysis: The video microscope accessory delivers sub-sample precision at a fraction of the cost of conventional Raman microscopes.

Future Trends and Potential Applications

• STRaman™ Technology: Ongoing development of low-power, temperature-controlled excitation sources for thermally sensitive substances.
• Enhanced SERS Substrates: Next-generation nanoparticle coatings designed for broader chemical compatibility and higher enhancement factors.
• Cloud-Based Spectral Libraries: Integration with online databases and AI-driven matching algorithms to streamline compound identification.
• Miniaturization and Wearables: Emerging ultra-compact Raman modules for unmanned aerial vehicles and body-worn forensic sensors.

Conclusion

B&W Tek’s Raman Solution Suite delivers a unified approach to forensic analysis, combining handheld speed with laboratory precision. By offering interchangeable laser wavelengths, SERS capability and microscopic sampling, the portfolio empowers analysts to tackle diverse forensic challenges in the field or the lab without sacrificing accuracy or sample integrity.

References

• B&W Tek. Raman Solution Suite for Forensics Applications. Application Note 410000024-B, June 2018.
• Scientific Working Group for the Analysis of Seized Drugs (SWGDRUG). Category A Analytical Methods, Version 7.1, 2016.