Abstract: Provided herein are methods of assessing or validating a cleaning procedure of a biotherapeutic manufacturing process, said method comprising analyzing by a surface plasmon resonance (SPR)-based assay the binding activity of a cleaned sample to a ligand which binds to a biotherapeutic produced by the manufacturing process. In various embodiments, the cleaning procedure comprises one or more steps to inactivate and/or degrade the biotherapeutic. In various instances, the method demonstrates that greater than about 99.99% degradation of the therapeutic is achieved by the cleaning procedure comprising the one or more steps to inactivate and/or degrade the biotherapeutic.