Research Intrests

RESEARCH INTERESTS

My research interests span a wide range of experimental interdisciplinary areas at the interface of Biophysics, Biochemistry, Biomedicine and Bionanotechnology. My PhD research was focused on polymer and peptide-based nanostructured biomaterials design, fabrication, characterization and their potential life science applications. Electrospinning and layer by layer (LBL) self-assembly multilayer has been used as two major fabrication techniques. Several spectroscopic and electron microscopic techniques has been used as characterizing techniques. Materials of particular interest are nanocoatings for cell and tissue culture, nanocoatings for medical implant devices, nanocoating for drug delivery and nanostructures electrospun nanofibers for biomedical applications.

ELECTROSPINNING

Electrospinning is a materials processing method which is used to fabricate continuous, ultra-fine fibers of nano to micro-scale diameter from polymers in solution. The approach is versatile, inexpensive, scalable and reliable. Various polymers, additional solutes and solvents are compatible with successful spinning. The structure, chemical and mechanical stability, functionality, and other properties of electrospun fibers can be tailored for specific applications. A variety of physical properties of the spun materials can be controlled by polymer properties and processing parameters.

To date, however, various organic polymers dissolving from organic solvents have been used in electrospun fibers for biomedical applications. Even protein-based fiber production has relied on extraction of proteins from an animal or a plant source, solubilization of proteins in organic solvents, or addition of non-natural organic polymers to the protein solution feedstock - all potentially problematic for regulatory approval, consumer acceptability, environmental toxicity and all kinds of complications. These importance and shortcomings led us to explore electrospinning of synthetic and microbial synthesis polypeptide

The most novel and innovative features of the project are as follows: the nature of the work is highly interdisciplinary, situated in the intersection of physics, biology, biochemistry biomedical engineering and material sciences. Electrospinning itself is versatile, inexpensive, scalable and reliable material processing technique. The structure, chemical and mechanical stability, functionality and other properties of electrospun fibers can be tailored for specific applications by manipulating polymer sequence and controlling processing parameter. Proteins account for about half of the dry mass of any living cell and advantage of peptide-based materials is that the breakdown products are in general biocompatible, biodegradable, bioabsorable and non-toxic. Pioneering of this project is use of synthetic peptides or recombinant peptides from water in electrospinning provides a way of avoiding the use of animal source materials and organic polymers as polymers and organic solvents as solvents. Electrospun fibers made of polymers are promising for product creation in the biosciences, bioengineering and medicine.

Applications of the electrospun materials are wide-ranging, encompassing filtration devices, textiles, electrical and optical components, and sensors. Arguably, one of the most promising application areas for modern electrospinning is biomedical materials.(read more).

LBL SELF ASSEMBLY

The layer-by-layer assembly (LBL) is a multi-component, nanostructured thin film fabrication technique which features many advantages for preparing ultrathin films from polyelectrolyte. It is a simple, versatile and scalable method of preparing multilayer films having a large thickness on the nanometer scale. The basic principle of this technique is the Coulombic attraction and repulsion. In a typical film buildup process by LBL, a solid support having a negative surface charge is immersed successively in a polyanion solution and a polycation solution, with a rinsing step following each polymer adsorption step. Applications of the method exist or are being developed in a wide range of areas, including biomimetics, biosensors, drug delivery, protein and cell adhesion, mediation of cellular functions, optical coatings, medical implant coatings and biosensors.(read more).

RESEARCH EXPERIENCE

Graduate Research Assistant, Department of Physics, University of South Florid, USA, 2008-Present

• • Broad foundation in material sciences

  • Electrospinning of polypeptide-based nanofiber and characterization of their physical, chemical and biological properties

  • Fabrication of polypeptide multilayer nanofilm and characterization of physical, chemical & biological properties

  • Bacterial gene expression and purification

  • Enzyme kinetics study

  • Nanoparticle drug delivery

  • High/Ultra-High vacuum technology

  • Clean room technology

  • Spectroscopic, acoustic and microscopic advanced material characterization methods: - UV-vis, CD, QCM, AFM, FTIR, SEM, SEM-EDS, DLS, XRD

Guest Researcher BioLaminex, Inc. Tampa, FL USA, August 2012 – December 2012

• • Polypeptide-based materials for tissue culture and other biomedical applications

Graduate Researcher Department of Physics, University of Southern Mississippi, Hattiesburg, Mississippi, USA, 2007-2008

• Computational assimilation using FORTAN and C++ programming

Graduate Researcher Tribhuvan University, Kathmandu, Nepal July 2002-December 2005

• • Ceramic material fabrication, electrical properties characterization & application