Clarifying cell culture broth is the first downstream unit operation in an elaborate sequence of steps required to purify a biological therapeutic. A combination of centrifugation, depth filtration, or tangential-flow filtration (TFF) is used for that operation. The availability of largescale, single-use, depth filtration technology in the recent years, however, has given process developers the capability to improve and simplify downstream processes.   Clarification of Cell Culture Streams   The main purpose of clarification is to efficiently separate…