Contemporaneous cell spreading and phagocytosis: Magneto-resistive real-time monitoring of membrane competing processes

► Magnetoresistive sensing of cell spreading and particle phagocytosis demonstrated. ► Cells uptaking particles saturate at a smaller spreading area than reference cells. ► Difference in spreading area accounts for required membrane area for phagocytosis. ► Sensor signal leads to average bead-to-surface distance of 120 nm after uptake. ► Uptake efficiency of spreading cells is 4 times higher compared to confluent cells.