How does tangential flow filtration (TFF) work and what are its applications?

TFF passes feed tangentially across the membrane surface rather than perpendicularly, reducing fouling and enabling higher throughput. Key parameters include transmembrane pressure (TMP), crossflow rate, and flux. Operating modes: concentration (remove permeate to increase product concentration), diafiltration (buffer exchange by adding diluent while removing permeate), and harvest (separate cells from product). Applications include cell harvest and clarification (microfiltration, 0.1-0.5 um), protein concentration and buffer exchange (ultrafiltration, 10-100 kDa MWCO), and virus removal (nanofiltration). Single-pass TFF eliminates recirculation for shear-sensitive products. Process development optimizes membrane selection, flux, and TMP for each application.