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Supramolecular peptide amphiphile (PA) nanofibers are polymerized with the polydiacetylene backbone while retaining the shape of the nanostructure. The polymerization of monomers in peptide amphiphile assemblies by a rigid conjugated backbone has led to mechanical robustness and insolubility, which are important properties for the patterning of these materials at the cellular state.

A phase diagram is constructed for self-assembling biologically active peptide amphiphiles. The changing solution conditions have resulted in phase transitions among these structures.

A strategy for the one-step fabrication of a nanostructured hybrid material containing oligo(p-phenylene vinylene) (OPV) segments and silicate is presented. The results indicate that the ordered and nanostructured environment leads to highly efficient energy transfer among organic components in these hybrid films.

A study of the aqueous solvation within self-assembled structures formed from peptide amphiphiles is conducted. The findings indicate that covalently bound fluorophores within an aggregate can interact with the external environment.

A series of amphiphilic molecules consisting of oligo(phenylene vinylene) (OPV) asymmetrically end-substituted with a hydrophilic poly(ethylene glycol) (PEG) segment and a hydrophobic alkyl chain is synthesized. This amphiphilic structure induces self-assembly into both thermotropic and lyotropic lamellar liquid crystalline (LC) phases.

The syntheses of convergent and divergent organic hybrid structures known as dendron rodcoils, which contain dendritic, rodlike segments, are explained. A number of catalyzed esterification reactions and silyl deprotection chemistry methods are used for the construction of these structures.

Research was conducted to perform direct templating of CdS as well as other semiconducting solids in the preordered environment of a nonionic amphiphilic mesophase, generating semiconductor-organic superlattices having both the symmetry and long-range order of the precursor liquid crystal. Results illustrate the importance of both chemical nature and structure of the amphiphile in direct templating. It is proposed that the interactions of polar segments in template molecules with the precipitated mineral and with its precursor ions are important conditions for direct templating.

Cryogenic electron microscopy is used to directly observe the nanostructural transformation from a twisted ribbon to a helical ribbon in supramolecular assemblies of peptide amphiphiles. The findings for the metastable states in the peptide aggregation could provide better insight into the amyloid-related diseases, such as Alzheimer's disease.

A series of peptide amphiphiles (PAs) with modified amino acid sequences is prepared to control the mechanical properties of the nanofiber gels they form by self-assembly. Molecular control of mechanical stiffness in three-dimensional artificial peptide amphiphile matrices has provided a chemical strategy to control biological phenomena such as stem cell differentiation and cell morphology.

The studies have shown that anionic and cationic amphiphiles of unequal charge has coasssembled into small buckled vesicles. The strong electrostatic interaction between the +3 and -1 head groups has increased the cohesion energy of the amphiphiles and has favored the formation of two-dimensional, flat ionic domains on the vesicle surface, resulting in edges and a buckled shape.

A quadruple helical fiber formed by photoresponsive peptide amphiphile (PA) and its conversion into single fibers upon photochemical cleavage of the 2-nitrobenzyle group in PA is described. This discovery has suggested novel strategies for creating dynamic functions in materials through the transformation of higher-order supramolecular architectures by using external stimuli such as light.

An analogous strategy is described for controlling the length of a self-assembled nanofiber by using a rigid template. The shape control within the molecular template has led to greater complexity in the supramolecular nanostructure.

The self-assembly of peptide amphiphile (PA) molecules, which is governed by hydrophobic interactions between alkyl tails and a network of hydrogen bonds between peptide blocks, is analyzed. The results have shown that the formation of nanofibers of peptide amphiphiles have obeyed an open association model, resembling living polymerization.

The hydrolysis of a model ester compound, 2,4-dinitrophenyl acetate (DNPA), on the surface of nanofibers formed by aggregation of peptide amphiphiles is described.

The fluorescence of bimolecular coassemblies that form one-dimensional nanaostructures is described. It is shown that coassembly of peptide amphiphiles (PA) is a powerful way to modify the fluorescence intensity of chromophores on the periphery of nanofibers.

The dendron rodcoil (DRC) molecules is found to have a triblock structure consisting of a generation of 3,5-dihydroxybenzoic ester dendron, a ter(biphenyl ester) rod, and a 3,7-dimethyloctyl coil. The three DRC molecules that show helical supramolecular assembly are found to induce gelation at low concentration.

The design, synthesis and characterization of 'reverse' peptide amphiphiles (PAs) with free N-termini are described. This class of reverse PAs has made it possible to create biologically significant assemblies with free N-terminal peptide sequences, which were previously inaccessible including those, derived from phage display methodologies.

The synthesis and self-assembly of a series of three molecules with dendron rodcoil architecture that contain segments of oligo(thiophene), oligo(phenylene-vinylene), and oligo(phenylene) are reported. The self-assembling behavior and electronic properties are investigated and it was also found that electric field alignment of these supramolecular assemblies could be used to create arrays of self-assembled nanowires on a device substrate.