We are interested to study structure-property relationship in various macromolecular and supramolecular systems. Our research interest can be broadly classified in three different areas:
Nano-structured aggregates such as micelle, vesicles etc. are of interest due to their container property in water. For biological applications of such aggregates, macromolecules are often preferred over small molecule amphiphiles due to the size, stability and lower critical aggregation concentration of the aggregates. We wish to develop synthetic strategies for making various amphiphilic macromolecules and tune their aggregation property by structural variations in the molecular level. Our particular interest is to study dendrimer-linear block copolymer, dendrimer-peptide conjugates, foldamers and self-destructive polymers. Our long-term goal is to utilize these aggregates as improved drug and gene delivery vehicles. Following are the TEM/SEM images of various exciting nano-structured assemblies those we have achieved recently from various novel synthetic amphiphilic polymers.
Organic semiconductors are important components of various optical devices such as solar cell, filed effect transistor, light-emitting diodes etc. Macroscopic ordering of chromophores plays an important role in device efficiencies. In order to achieve desired macroscopic properties we wish to develop novel supramolecular designs to generate higher order self-assembled structures of various organic semiconductors, electron transporting materials and NLO chromophores. Our current interest is to examine various self- assembly modes of Naphthalenediimide (NDI) and Dialkoxy-naphthalene (DAN) derivatives. In the recent past we have demonstrated various novel strategies to achieve facile supramolecular assemblies of such functional pi-systems individually as well as in their mixtures. Following are the pictures showing self-assembled organogels derived from suitably functionalized NDI, DAN and their mixtures. Various exciting nano-structures could be achieved based on such self-assembled pi-systems as shown below.
Representative microscopic images (SEM, TEM, AFM) showing morphology of various self-assembled donor (DAN) and acceptor (NDI) materials
Today synthetic methodologies to achieve desired polymer includes various controlled polymerization pathways that enables one to synthesize macromolecules with precise control over molecular weight, composition, end group and architecture. This also opens up the possibility to develop new functional polymeric materials to explore the possibility of them being used in various sophisticated biological and material science application which was not feasible before. We are currently engaged in developing such novel polymeric materials (mainly synthetic polypeptides/polylactides based block copolymers) based on specifically designed functional monomer and initiator units.