Raman spectroscopy as a novel analytical bioprocessing tool for PAT

Protein-based biopharmaceuticals are becoming increasingly widely used as therapeutic agents and biotherapeutics; for example antibody therapy is become very popular and is used for explicit diseases and helps the immune system. These proteins are manufactured within cells and in order for them to be active they need to be produced and purified in the correct way. Whilst some methods do exist they are laborious and destroy the sample. By contrast we will develop a method based on the interaction of light with matter that will enable a very powerful and non-invasive analysis. One process that happens when light is shone at a substance is that it is scattered and sometimes this light is scatter at a different wavelength; an effect named Raman scattering. We will therefore develop Raman spectroscopy as a novel method for the direct in situ analysis of the production process, thereby allowing more rigorous assessment of these protein-based biopharmaceuticals.

This project will develop Raman spectroscopy with appropriate chemometric modelling as a novel analytical tool for high-throughput monitoring of biopharmaceutical processes. This will be employed throughout the whole production phase and in particular for in situ measurements in fermentation broths for assessing the levels of post-translational modifications to antibodies and non-antibody products (e.g., clotting factors), and to aid downstream product recovery by measuring the structure of purified proteins. During the course of the work the Raman spectroscopic approach will be benchmarked against purified antibodies and the same antibodies after modification (enzymatic deglycosylation and proteolytic degradation) as well as fermentation broths from mammalian cell lines producing antibodies. The later will also be performed using a tangential flow system to separate cells from fermentation broths thus allowing on-line analysis. Finally, we shall also develop Raman spectroscopy for the assessment of protein aggregation.