In-line Protein Concentration Measurement Application Note

This application note details the integration of the KrosFlo® RS 30 tangential flow filtration (TFF) system with the CTech FlowVPX® spectrophotometer for in-line protein concentration measurement. The document outlines the preparation of a bovine serum albumin (BSA) solution and the setup of the filtration system, which includes a single-use Tulip tank bag and a TangenX® cassette. The process is monitored in real-time using the FlowVPX instrument, which allows for automatic transitions based on actual concentration values rather than volume concentration factor (VCF) estimates. The application note describes the ultrafiltration/diafiltration (UF/DF) process, detailing the stages of concentration and diafiltration, and presents data showing the accuracy of the FlowVPX measurements compared to off-line methods. The results indicate that the integrated system effectively maintains target concentrations throughout the process, demonstrating its reliability and precision in monitoring protein concentrations in a cGMP environment.