@unpublished{pittir36867, month = {June}, title = {Establishing Design and Assembly Rules for Peptide Oligonucleotide Chimeras (POCs)}, author = {Teesta Dasgupta}, year = {2019}, keywords = {self-assembly}, url = {http://d-scholarship-dev.library.pitt.edu/36867/}, abstract = {Peptide Oligonucleotide Chimeras (POCs) are an emerging class of soft materials which offer tremendous potential in a variety of therapeutic applications owing to both the peptide and oligonucleotide components. These applications often depend upon the high selectivity, tunability and self-assembly behavior of the POCs. Therefore, a thorough understanding of the nature and self-assembling properties of POCs could allow for synthesis of POCs that meet the criteria of a specific application. The goal of this work is to probe the effects of hydrophobicity and {\ensuremath{\beta}}-sheet character on the self-assembly properties of POCs. Here, the nature of assembly and morphological changes of oligonucleotide-biphenyl-peptide conjugates (oligonucleotide = AACAATTATACTCAGCAA, AACAATTATACTCACCAA; peptide = AAAYSSGAPPMPPF, AAAYVVAAPPMPPF, AAAYVFAAPPMPPF, AA(AIB)Y(AIB)SG(AIB)PPMPPF) were studied over a range of salt concentrations (CaCl2). The presence or absence of assembled structures, morphology of discrete nanostructures (spheres or fibers) and salt concentration at point of transition from spheres to fibers is probed for each analogue with respect to hydrophobicity and {\ensuremath{\beta}}-sheet character of the peptide. It was observed by transmission electron microscopy (TEM) that no ordered structures are formed in the absence of {\ensuremath{\beta}}-sheet character and higher hydrophobicity of peptides led to a shift from exclusively spheres to a combination of fibers and spheres at the same salt concentration. This study will provide the basis for the design of future POCs with programmable structures and properties.} }