The United States built special reactors between 1944 and 1988 to make about 100 metric tons of plutonium for nuclear weapons. The production of nuclear armaments generated more than 100 million gallons of hazardous liquid waste, which is to be safely cleaned up and disposed of by The US Department of Energy (DOE). Vitrification and grouting are the plans the DOE has come up with to permanently deal with the waste. These approaches ineffectively collect the radioactive content of the waste necessitating an alternative cleanup strategy. Peptides have the potential to collect the radioactive content present in the waste through selective binding in order to provide efficiency in nuclear waste treatment. Moreover, expanding chemical space beyond the genetically encoded amino acids endows biomolecules with unique properties. As nature harnesses chemical (post-translational) modifications, we seek to incorporate pyrazole heterocycle into peptide scaffolds due to their ability to provide either an H-donor or acceptor through tautomerization. The introduction of synthetic fragments into genetically encoded peptide libraries makes it possible to equip these peptide libraries with value-added functionality uncommon in natural peptides. Discovering adequate peptide ligands for such purpose can be done using phage display technology. Therefore, we will utilize high-throughput techniques (i.e., phage display) to fabricate modified peptides to both understand the role of peptide structure on employed techniques and synthesize biomaterials with intriguing properties relevant to nuclear waste remediation.

Probing the chemistry regarding a modified phage peptide library offers opportunities for the discovery of strong affinity-binding peptides. This will provide a comprehensive understanding of phage peptide modification, immobilization of radionuclides, and peptide metal binding. Developing a protocol to immobilize perrhenate, surrogate to pertechnetate, via ion exchange resin and sequestration using modified/unmodified peptides, would improve the treatment of nuclear waste. This will _further our understanding of technetium chemistry and provide new opportunities for the selective sequestration of this problematic species from radioactive tank waste. Waste facilities in the world, specifically the US, will greatly benefit from the environmentally benign method of treating nuclear wastes with peptides. The research will significantly impact various departments of waste treatment facilities and broaden the general usage of phage display technology. Moreover, it will provide general methods for the modification of phage peptides, immobilization of metal targets, and identifying appropriate peptide ligands.

The efficiency of the modification of phage display peptide was highly successful. This result establishes a firm idea and procedure which will be used to develop bioconjugation on model peptides and phage-displayed peptide libraries. Moreover, bioconjugation strategies targeting Cys are among the most mature and can be used to incorporate heterocycles within peptides. The screening of unmodified phage library for metal binding was successful in which promising peptide was identified. This identified peptide will be used in subsequent analysis to ascertain its binding efficiency. The strategy provides distinct opportunities for selective sequestration of problematic metal species in the processing of nuclear tank waste, environment remediation, and other applications.