Rapid Testing of Solvents Through Amber Bottles using an Agilent Vaya Handheld Raman Spectrometer

Significance of the Topic

The capacity to noninvasively verify raw solvents is critical in biopharmaceutical manufacturing to uphold quality and reduce contamination risk. Spatially offset Raman spectroscopy (SORS) through amber bottles accelerates warehouse material checks and aligns with regulatory standards.

Objectives and Study Overview

This study evaluates the Agilent Vaya handheld Raman spectrometer with SORS for rapid, through-barrier identification of key organic solvents used in biotherapeutic production. The goal was to develop pass/fail methods for methanol, ethanol, isopropanol, acetonitrile, and toluene without opening amber bottles.

Methodology and Instrumentation

A method development wizard on the Vaya device configured acquisition parameters specific to amber glass. Performance qualification was carried out prior to spectral collection. Ambient light conditions prevailed during data acquisition. Minimal postprocessing was applied, relying on the instrument’s automated baseline corrections.

Instrumentation

• Agilent Vaya handheld Raman spectrometer equipped with SORS technology
• Amber glass bottles from Sigma-Aldrich containing analytes

Main Results and Discussion

Distinct Raman signatures for each solvent were recorded in under 35 seconds. Key spectral markers include:

• Methanol: strong C–O stretch at ~1033 cm^–1 and CH₃ deformation at ~1464 cm^–1
• Ethanol: C–C stretch at ~886 cm^–1 and C–O stretch/CH₃ rocking near 1050–1098 cm^–1
• Isopropanol: C–C–O vibration at ~820 cm^–1 with additional bands at 954 and 1454 cm^–1
• Acetonitrile: skeletal C–C mode at ~921 cm^–1
• Toluene: aromatic ring stretches at ~1001 and 1032 cm^–1

A challenge matrix demonstrated high diagonal pass rates and negligible off-diagonal matches, confirming selectivity and reliability for raw material identification.

Benefits and Practical Applications

This noninvasive approach eliminates sample exposure and contamination, streamlines incoming QC protocols, and supports compliance with ICH guidelines for raw material verification.

Future Trends and Opportunities

Expanding spectral libraries, integrating with laboratory information management systems, and applying machine learning for automated anomaly detection are anticipated developments. Further miniaturization and enhanced sensitivity could extend SORS applications to colored or thicker containers.

Conclusion

The Agilent Vaya SORS handheld Raman spectrometer effectively identifies common solvents through amber glass, delivering rapid, reliable pass/fail results and enhancing biopharmaceutical raw material workflows.

References

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