Multi-Material Aerosol Jet Printing of Al/Cuo Nanothermites for Versatile Fabrication of Energetic Antennas

In the present study, a nanoscale Al/CuO thermite system is patterned using a multi-material aerosol jet printing technology. Morphological analysis of samples manufactured with different printing configurations reveal a strong effect of the printhead design on microstructure and degree of mixing between the constituent materials, providing insight on fundamental mechanisms of inline aerosol-phase mixing during printing. The high-resolution patterning capability of aerosol jet printing is leveraged to fabricate both blended nanoscale Al/CuO thermites and antennas containing the nanothermite, which exhibit rapid and low-energy ignition upon exposure to a 2.45 GHz free space electromagnetic field, characterized by an ignition delay of ≈130 ms and ignition energy of ≈216 J. Moreover, the versatility of this approach is demonstrated by manufacturing compositionally graded samples, establishing multi-material aerosol jet printing as a compelling and versatile platform for microscale energetic device fabrication with broader utility for graded materials. This work shows promise for use of the technique for in situ manufacturing of standalone and integrated energetics and electromagnetic devices.     

Development of Multivalent Conjugates with a Single Non-Canonical Amino Acid

Proteins represent powerful biomacromolecules due to their unique functionality and broad utility both in the cell and in non-biological applications. The genetic encoding of non-canonical amino acids (ncAAs) facilitates functional diversification of these already powerful proteins. Specifically, ncAAs have been demonstrated to provide unique functional handles to bioorthogonally introduce novel functionality via conjugation reactions. Herein we examine the ability of a single ncAA to serve as a handle to generate multivalent bioconjugates to introduce two or more additional components to a protein, yielding a multivalent conjugate. To accomplish this aim, p-bromopropargyloxyphenyalanine (pBrPrF) was genetically encoded into both superfolder green fluorescent protein (sfGFP) and ubiquitin model proteins to serve as a conjugation handle. A sequential bioconjugation sequence involving a copper-assisted cycloaddition reaction coupled with a subsequent Sonogashira cross-coupling was then optimized. The linkage of two additional molecules to the model protein via these reactions yielded the desired multivalent bioconjugate. This domino approach using a single ncAA has a plethora of applications in both therapeutics and diagnostics as multiple unique moieties can be introduced into proteins in a highly controlled fashion.