SUMMARY Biological pharmaceuticals, or “biologics”, are among the most important pharmaceuticals in development today, and their safe manufacture is absolutely crucial for human health. A major problem faced by operators of bioreactors, at both the laboratory scale and industrial scale, is microbial contamination as an integral risk of any process that derives from live cell lines. The fundamental concern is to ensure that contaminated biologics are not injected into the human body. To warrant contamination free biologics a terminal sterilization is often necessary. The central challenge in this step is the inactivation or removal of microbial contaminates without causing harm to the precious biologics. This work focuses on antibodies as representative biologics. Especially for viral and mycoplasma contaminations the terminal sterilization step remains challenging due to the small size of the pathogens. The industry standard today is removal through passive filtration using filter membranes with pore diameters smaller or of the same size as the virus particles. This approach requires, however, long processing times associated with high costs. Furthermore, ultrafiltration can induce antibody self-association and is not compatible with emerging flexible, small-scale, point-of-care biologics fabrication technologies. The need for new selective microbe inactivation strategies is also not limited to the field of biologics fabrication. The Covid19 pandemic has recently illustrated the need for reliable virus inactivation strategies that selectively act on the virus in tissues but not on proteins, for instance, to allow immunological assays of infected samples outside of high containment laboratories. Light has sterilization properties, and UV-light has long been used to inactivate a broad range of microbial pathogens. Unfortunately, it lacks specificity and also damages precious biologics through reactive photochemistries driven by molecular absorptions in the UV range of the electromagnetic spectrum. To overcome the shortcomings of both ultrafiltration and UV-irradiation as microbe inactivation strategies, this proposal develops a plasmonically enhanced photonic inactivation method that utilizes near-infrared (NIR) light for the selective inactivation of viruses and mycoplasma. As NIR radiation does not overlap with molecular absorptions, the collateral damage on biologics is minimal. The proposed work will reveal the fundamental working principles underlying plasmonic pathogen inactivation and implement magnetic plasmonic nanoparticles (NPs) that allow for an easy, contact-free removal of the nanomaterials from the samples after sterilization. The specific aims of this application are to: Aim 1: Achieve Reliable Virus Inactivation with NIR Light through Plasmonic Enhancement Aim 2: Demonstrate a Plasmon-Enhancement Strategy for Mycoplasma Inactivation with NIR Light Aim 3: Demonstrate Scalable Clearance of Virus and Mycoplasma with Magnetic Plasmonic...