Project Summary/Abstract Viable cell concentration is one of the most important key performance indicator during upstream technologies in mammalian cell culture. Customer Discovery discussions with biopharma execs and R&D specialists revealed there is an unmet need for on-line/in-line monitoring of cell viability in pharma bioreactors driven by compliance with real-time product quality assurance as described in Process Analytical Technology (PAT) and Quality by Design initiatives. Preliminary work equivalent to Phase I effort has resulted in a cell imaging system including a flow cell setup that simulates an on-line stirring bioreactor sampling route. Proof-of-concept was also established for detection and classification of live/dead assays using digital staining via PICS (Phase Imaging with Computational Specificity). This Small Business Innovation Research project proposes to build a commercial prototype instrument for real time, quantitative and high-throughput cell viability scoring for on-line/in-line bioreactor monitoring that meets the metrics of interest for pharma R&D applications. During this effort the standard operation of the QPI+PICS instrument will be refined and the automated software detection and classification of live/dead assays will be completed. At the end of this Direct Phase II project we will deliver a commercial prototype -a “push-of-a-button” viability scanner with the above capabilities built in.