Quantification of clinical mAb solutions using Raman spectroscopy: Macroscopic vs microscopic analysis

Area of Science:

• Analytical Chemistry
• Biotechnology
• Spectroscopy

Background:

• Raman spectroscopy is a valuable tool for Analytical Quality Control (AQC).
• Its non-invasive nature allows direct sample analysis within containers.
• Monoclonal antibodies (mAbs) are critical biopharmaceuticals requiring robust quality control.

Purpose of the Study:

• To investigate the potential of Raman spectroscopy for analyzing clinical preparations of monoclonal antibodies (mAbs).
• To assess the feasibility of both macroscopic (cuvette) and microscopic (perfusion bag) analyses.
• To compare spectral data with excipients and γ-Globulin to understand band origins.

Main Methods:

• Analysis of three commercial mAb formulations (Bevacizumab, Trastuzumab, Atezolizumab) using Raman spectroscopy.
• Spectra acquisition in quartz cuvettes and through perfusion bag walls.
• Quantitative analysis using Partial Least Square Regression (PLSR) with Leave K-Out Cross Validation (LKOCV).

Main Results:

• Raman spectra confirmed contributions from both mAbs and their excipients (trehalose, sucrose).
• Quantitative analysis models demonstrated comparable performance (error, linearity) for macroscopic and microscopic measurements.
• Spectra were successfully deconvoluted to identify mAb and excipient contributions.

Conclusions:

• Raman spectroscopy is a promising technique for the rapid, non-invasive AQC of mAbs.
• The method provides accurate quantification in both standard cuvettes and in-situ within perfusion bags.
• This supports future applications for in situ AQC in biopharmaceutical manufacturing.