Flow cytometry investigation and flow cytometry result analysis to determine an optimized dilution factor range for flow cytometry investigation of a target sample fluid stock using a flow cytometer. The optimized dilution factor range may be determined using a screening assay module of a flow cytometry system to analyze flow cytometry results determined to fall within a dynamic range of a flow cytometer to determine the optimized dilution factor range for a given flow cytometer to investigate a given target sample fluid stock. In turn, a titer assay module may be executed to prepare particle titer results based on optimized target fluid samples provided within the optimized dilution factor range. The screening assay module and/or the titer assay module may provide automated data processing with data notifications and confirmations to provide robust data analysis.