Department of Chemistry, Indian Institute of Technology, Kanpur

Department of Chemistry, Indian Institute of Technology, Kanpur

My Doctoral research involved the designing and developing synthetic functional materials composed of people units and polymers, self-assembly and utilization for diverse applications in biological, material sciences, and nanotechnology with following projects:

Projects

Folic acid based self-assembling peptide for drug delivery applications.

Folic acid (FA) is a low‐molecular‐weight micronutrient, which plays a critical role in the prevention of birth defects and cancers. It is also essential for biochemical pathways responsible for DNA synthesis and maintenance and for the generation of new red blood cells. Cellular trafficking of FA and folate is based on its high‐affinity binding to cognate folate receptor, a protein commonly expressed in several human cancers. Thus, folate conjugates of drugs, plasmids, biosensors, contrast, and radio diagnostic imaging agents have been used for assisted delivery in folate receptor‐positive cancer cells, via endocytosis pathways. This report describes morphologies of soft structures from a fully characterized FA–dipeptide conjugate and detailed mechanistic studies of its cancer cell uptake, as tracked by the inherent fluorescence of the conjugate.

Peptide-polymer nano-mats for cancer cell detection.

Electrospun polymer fibers are valuable for a number of applications ranging from catalysis to drug delivery. At times, lack of biocompatibility, biodegradability, and hydrophobicity presents hindrance in their use in biological applications. Aromatic amino acids are veritable precursors for biocompatible nanofibers, which could also be chemically modified with suitable addressable recognition tags to invoke specific binding events. This study presents an attractive strategy for constructing electrospun fibrous mats from dityrosine folic acid conjugate and polycaprolactone to afford a new biomaterial displaying excellent tensile properties, biocompatibility, and cell adhesion. We demonstrate that appropriate choice of peptide-to-polymer ratio gave mats with sufficient hydrophilic and better mechanical properties and allowed favorable interaction of folate receptor presenting cells with electrospun mats, while the ones lacking folate receptor did not exhibit binding. Such selectivity could be possibly invoked for separation and also for custom synthesis of nanomats for healthcare applications.

Design and synthesis of small self-assembling peptides for supercapacitor material applications.

Folic acid conjugated peptide explored for self-assembled behavior with architecture morphology similar to graphene sheets and studied for their electrochemical capacitive performance for application in energy storage field.

Small self-assembling L-phenylalanine based peptides for metal-peptide frameworks (MPF) for catalytic application.

Peptides and proteins offer interesting starting points for triggering self-assembly processes owing to the chemical diversity of side-chains, ease of chemical modifications and the possibility of exploiting several non-covalent and metal-assisted interactions, to stabilize higher order ensembles. Consequently, a variety of nanoscale morphologies such as fibers, vesicles, nanotubes are observed for modified amino acids and short peptides and these biocompatible soft materials have been used for diverse biological, medical and material applications. Herein, we report metal-mediated modification of spherical soft assemblies, by introducing a coordinating linker for the Phe–Phe dipeptide, which results in the coalescence of soft structures. The possibility of copper ion coordination, with the metal-binding peptide conjugate, was confirmed by single crystal analysis. Based on these observations, a model depicting possible interactions leading to soft structure formation and metal-aided coalescence is also presented. The coalescence could be reversed in the case of Au-mediated soft structures with the help of thiol interference. Such an approach, exploiting interfacial metal ion interactions, is expected to provide an entry into novel metallopeptide materials.

Design and synthesis of covalent organic framework for material science applications such as gas storage material and catalysis.

Covalent organic framework (COP) has been synthesized and explored for various applications such as gas storage materials and catalysis.

Thesis: Ordered Peptide-based Assemblies as Functional Materials

My doctoral research involved the design and implementation of synthetic self-assembling biomaterials composed of small peptides and polymers, their utilization in biology and nanotechnology applications.