How are Downstream processes (DSP) currently monitored in the biopharmaceutical industry ?

During a purification process, pH, temperature and absorbance are usually controlled by the purification equipment itself (in-line data).

On the other hand, the product of interest and impurity concentrations are measured off-line by colorimetric assays, ELISA, HPLC, etc. In order to insure a good product quality, numerous sampling are required all along the process. Data could be acquired after a delay of several weeks!

How real-time monitoring could be implemented at the different step of DSP?

Upstream Cell culture (USP)