2D fluorescence spectroscopy for real-time aggregation monitoring in upstream processing

Product aggregation is one side effect of rising yields due to process improvement and therefore accompanied with massive product loss during downstream processing (DSP). But it is already in literature described, that product aggregation also occurs during the fermentation process and is caused by various process operations [1]. Real-time bioprocess monitoring and thus on-line product quality control during upstream processing (USP) enables to address this issue during process development. For bioprocess control, 2D fluorescence spectroscopy in combination with chemometric modeling based on fluorescence signals derived from cells and medium components is a promising tool and described in literature [2]. Furthermore extrinsic fluorescence dyes are widely used to detect and quantify aggregated protein [3]. In this study, 2D fluorescence spectroscopy in combination with three different extrinsic fluorescence dyes were evaluated, in order to establish a process control tool which enables real-time product control during USP.