Metrohm STRam portable Raman spectrometer

Significance of the Topic

Raman spectroscopy offers rapid, non-destructive molecular identification, critical for applications where sample integrity and safety are paramount. Extending Raman analysis through opaque barriers addresses key needs in customs inspection, pharmaceutical QC, forensics and cultural heritage studies.

Objectives and Overview of the Study

This work presents the STRam portable Raman analyzer, designed to identify materials inside sealed or diffusive containers without direct access. Its goal is to combine high-throughput optics, sensitive detection and advanced algorithms to deliver reliable through-package identification across diverse sample types.

Methodology and Instrumentation

The STRam integrates:

• Laser modules at 785 nm and 1064 nm (up to 420 mW, adjustable in 1 % steps)
• High-throughput spectrometer with resolution <6 cm⁻¹ (912 nm) or <10 cm⁻¹ (1296 nm)
• High-efficiency CCD detector for 785 nm and InGaAs array for 1064 nm excitation
• Specialized fiber-optic see-through probes and adaptors for focused or large-area sampling
• Embedded tablet running 21 CFR Part 11-compliant BWID-Pharma software with STID algorithms
• Optional battery pack for field portability and USB 2.0 interface with trigger compatibility

Technical specifications cover spectral ranges of 150–2800 cm⁻¹ (785 nm) and 100–2500 cm⁻¹ (1064 nm), integration times from milliseconds to 30 minutes, and operation in ambient conditions (0 °C–35 °C, 10 %–85 % RH).

Key Results and Discussion

By exploiting patented STRaman® technology, the STRam retrieves Raman signals beneath diffusive layers, enabling reliable identification inside plastic bottles, paper bags and other opaque packages. Its large sampling spot enhances reproducibility on heterogeneous materials, while minimized power density reduces risk to sensitive samples. STID algorithms rapidly match acquired spectra to built-in libraries for real-time decision support.

Benefits and Practical Applications

• Non-invasive through-barrier identification preserves sample and packaging integrity
• Portable, battery-powered design with embedded software enables field deployment
• Broad application scope: customs and logistics, narcotics detection, pharmaceutical raw material verification, art and archaeological analysis, bioscience, forensic and geological research
• Chemometric software (BWIQ®) supports multivariate analysis (PCA, PLS, SVM) for qualitative and quantitative tasks

Future Trends and Opportunities

Ongoing miniaturization of optics and detectors, coupled with AI-driven spectral interpretation, will further improve portability and identification accuracy. Expansion of spectral libraries and integration with complementary imaging modalities will open new avenues in environmental monitoring, medical diagnostics and process control.

Conclusion

The STRam portable Raman analyzer delivers research-grade, through-barrier material identification with high sensitivity and user-friendly compliance software. Its versatile design supports rapid, non-destructive analysis in both laboratory and field settings, meeting critical needs across multiple industries.

References

• B&W Tek, LLC. STRam Portable Raman Analyzer for Rapid Through-Barrier Identification, Doc-Rev: 280001279-G (2020/03/31).