Research Project 1

DEVELOPMENT AND APPLICATION OF NANOSCALE ARCHITECTURES FOR IMAGING AND ENVIRONMENTAL PROTECTION

(Ray, Hamme, Han, Hill, Hossain, Leszczynski, Li, Liu, Yu)

Plasmonic, magnetic and flexible multifunctional nano-graphene architecture: Graphene, single sp2-bonded carbon atom sheets, is emerging as a highly novel material due to its unique physical, chemical, electrical, mechanical, thermal, and optical properties. Attaching plasmonic and magnetic nanoparticles on graphene sheets will allow us to get desirable plasmonic and magnetic properties into graphene oxide architectures. As a result, the multifunctional hybrid materials will be highly promising for a variety of applications in biology, energy storage, catalysis, and environment. Our aim is to use different synthetic procedures for covalently attachment of plasmonic and magnetic nanoparticles with grapheme sheets. The REU students will be involved in synthesis and characterization of the multifunctional graphene sheets.

Selective capture of several bacterial pathogens from water sample using bio-conjugated multifunctional nano-architectures: The goal of this subproject is to use antibody/aptamer conjugated multifunctional graphene/gold NP/magnetic NP based hybrid material for multimodal detection of several waterborne pathogens such as Escherichia coli, Salmonella, and Shigella selectively and simultaneously. We plan to use surface enhanced optical properties, magnetic imaging and field effect transistor properties of the multifunctional nanomaterial for multimodal sensing. Our other aim is to understand the detailed mechanism and the working principles for the sensor systems. The REU students will be involved in designing nanomaterial based sensors for pathogens detection from environmental samples.

Selective removal of toxic heavy metal ions from drinking water using multifunctional nanoscale architectures: The goal of this subproject is to use chemically modified multifunctional grapheme sheets for multimodal detection and filtration for removal of toxins such as CN-, Cr(VI), As(III), As(V), Hg(II), Pb(II) selectively and simultaneously. We plan to use surface enhanced Raman spectroscopy, magnetic imaging and field effect transistor properties of the multifunctional nanomaterial for multimodal sensing. Then we will demonstrate that multifunctional graphene sheets can be used for filtration of chemical toxins from water samples. We also want to understand the mechanism and working principles for the sensor systems. The REU students will be involved in synthesis and characterization of different multifunctional nanomaterials, surface modifications with antibodies, and finding its use for removal of pathogens and toxic metals.

Sensing of anions with polyamide-attached gold nanoparticles: This supramolecular chemistry research project will focus on molecular sensors for the detection of anions of environmental and biological relevance. In this project, the plan is to focus on common inorganic anions, halides, pseudohalides, and oxoanions which are known pollutants in the environment. The aim is to use polyamide attached gold nanoparticles for selective sensing. The REU students will be involved in synthesis and characterization of polyamide macromolecules, modification of gold nanoparticles, and finding its use as optical sensors for various anions.

Hybrid graphene oxide architecture based filter for water purification: Due to the presence of a huge number of biological and chemical toxins, it is a real challenge to prevent waterborne pathogen and chemical toxin outbreaks 63-72. On the other hand, to protect public health, this challenge must be met. Recently, it has been reported that graphene oxide based filter can be used for water purification25-40. Our aim is to develop and characterize gold nanoparticle attached hybrid graphene oxide-based filter for removal of bacteria and chemical toxins like Hg(II), Pb2+, and As3+ from water. The REU students will be involved in developing and characterizing hybrid materials and finding the use of these materials as filters for water purification from biological contaminations.

Theoretical modeling of nano-bio interaction: In this project, theoretical and numerical studies will be used to describe optical properties of metal nanoparticles with biomolecular adsorbates that are relevant for biosensing. The project will include microscopic calculations of fluorescence quenching efficiency for various fluorophores adsorbed on nanoparticles of various sizes and shapes, energy transfer processes between donor and acceptor molecules adsorbed at metal surface, and accurate calculations of radiative lifetimes for large numbers of fluorophores attached to a nanoparticle. The calculations will be carried out using time-dependent density-functional theory methods as well as electromagnetic calculations 97-99. The REU students will be involved in performing density-functional calculations for study of nano-bio interactions.