Capture Instead of Release: Defect-Modulated Radionuclide Leaching Kinetics in Metal-Organic Frameworks.

Comparison of defect-controlled leaching-kinetics modulation of metal-organic frameworks (MOFs) and porous functionalized silica-based materials was performed on the example of a radionuclide and radionuclide surrogate for the first time, revealing an unprecedented readsorption phenomenon. On a series of zirconium-based MOFs as model systems, we demonstrated the ability to capture and retain >99% of the transuranic 241Am radionuclide after 1 week of storage. We report the possibility of tailoring radionuclide release kinetics in MOFs through framework defects as a function of postsynthetically installed organic ligands including cation-chelating crown ether-based linkers. Based on comprehensive analysis using spectroscopy (EXAFS, UV-vis, FTIR, and NMR), X-ray crystallography (single crystal and powder), and theoretical calculations (nine kinetics models and structure simulations), we demonstrated the synergy of radionuclide integration methods, topological restrictions, postsynthetic scaffold modification, and defect engineering. This combination is inaccessible in any other material and highlights the advantages of using well-defined frameworks for gaining fundamental knowledge necessary for the advancement of actinide-based material development, providing a pathway for addressing upcoming challenges in the nuclear waste administration sector.

A biomaterials viewpoint for the 2020 SARS-CoV-2 vaccine development.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has caused a considerable loss of life, morbidity, and economic distress since its emergence in late 2019. In response to the novel virus, public and private institutions around the world have utilized novel technologies to develop a vaccine in the hopes of building herd immunity and ending the pandemic. This review provides an overview of mechanisms and available data on the nascent vaccine technologies undergoing clinical trials to combat SARS-CoV-2, namely, those using protein subunits, viral vectors, mRNA, and DNA. Furthermore, we discuss the potential uses of biomaterials in improving the immunogenicity and safety of these vaccine technologies with the goal of improving upon newly-available technologies to combat future SARS-CoV-2 strains and other emerging viral pathogens.