Metrohm i-Raman Pro portable Raman spectrometer

Significance of the Topic

Portable Raman spectroscopy with high sensitivity and resolution has become an invaluable tool across multiple fields, enabling on-site, non-destructive material identification and quantification. The integration of deep-cooled detectors and fiber-optic sampling extends the capability of conventional laboratory systems into diverse environments, supporting quality control, regulatory compliance, and real-time process analytics.

Study Objectives and Overview

This document presents a comprehensive overview of the i-Raman Pro, a fully integrated, portable Raman system designed to deliver laboratory-grade performance in the field. The goals include demonstrating its spectral range, sensitivity, stability, and user-friendly software suite, as well as outlining practical applications in research and industry.

Methodology and Instrumentation

The i-Raman Pro employs a high-quantum-efficiency CCD array detector cooled to –25 °C to minimize noise and maximize dynamic range. Excitation sources at 532 nm (35–42 mW) and 785 nm (340–455 mW) are adjustable in 1 % increments to optimize signal without damaging samples. Fiber-optic probes enable flexible sampling of solids, liquids, and powders in situ. Key specifications include:

• Spectral coverage from 65 cm⁻¹ to 4200 cm⁻¹ for comprehensive molecular fingerprinting
• Resolution down to < 3.5 cm⁻¹ (ASTM E2529-06 compliant)
• Integration times from 7 ms up to 30 minutes for weak Raman scatterers
• Battery operation and USB 2.0 computer interface for portable, stand-alone use

Comprehensive sampling accessories include long-working-distance lenses, immersion probes, video microscopy adapters, and flow cells to support applications from art conservation to process analytical technology.

Main Results and Discussion

The i-Raman Pro achieves high signal-to-noise ratios, even with extended integration times, due to deep cooling and high dynamic range. The wide spectral range captures low-frequency lattice modes and high-frequency C–H stretching bands, enabling detailed analysis across organic and inorganic materials. The touchscreen tablet and embedded software allow immediate spectral acquisition, library search, and quantitative predictions, streamlining workflows in regulated environments.

Benefits and Practical Applications

By combining portability, sensitivity, and software intelligence, the system supports:

• Art and archaeological pigment identification without sampling removal
• Bioscience and medical diagnostics through non-invasive tissue analysis
• Pharmaceutical QA/QC and counterfeit drug detection
• Forensic evidence verification at crime scenes
• Process monitoring (PAT) in chemical and bioprocess industries
• Geological, gemological, and materials science research in remote locations

Real-time multivariate analysis (PLS, PCA, SVM) via the BWIQ® package enhances quantitative accuracy and model interpretation directly in the field or laboratory.

Future Trends and Applications

Advances in detector materials and miniaturized electronics will further reduce system size while boosting sensitivity. Integration with cloud-based spectral libraries and machine-learning algorithms will enable automated identification of novel compounds and advanced process control. Emerging applications may include in situ environmental monitoring of pollutants, rapid infectious disease screening, and integration with robotic platforms for remote exploration.

Conclusion

The i-Raman Pro represents a versatile, high-performance portable Raman platform that meets the rigorous demands of research, industrial, and regulatory applications. Its combination of deep-cooled detectors, broad spectral range, and user-friendly software enables both qualitative and quantitative analysis across a spectrum of fields, making it an essential tool for modern analytical chemistry.