Chemistry and Biochemistry


Chanda Lowrance

Area of Doctoral Study: Chemistry
Undergraduate Institute: Metropolitan State University

Research Advisor: Marie-Christine Onuta, Ph.D.

Description of Research

The coupling of semiconductor quantum dots (QD) with anisotropic gold nanoparticles (AuNP) is of special interest because of the unique optical properties that the assembly exhibits, specifically induced transparency that results from Fano interference (intermediate coupling). Additionally, the theorized laser-induced “turn-on/off” optical properties of the AuNP-QD-AuNP assembly offer the prospect of application in quantum computing, ultra-small lasers, etc. Thus, in an initial stage, the synthesis of AuNP-QD nanoparticle dimer is essential to obtain a better understanding of these assemblies. Therefore, we propose a reaction scheme to functionalize gold nanobipyramids (AuBP) at their tips with an amine ligand, and to couple them with carboxylate-functionalized CdSe/CdS core-shell quantum dots to create the AuBP-QD dimer via amide bond linkage. Current research is being performed to increase the coupling yield, obtain better spatial control of the reaction, and isolate the novel nano-assemblies.


Giraso “Monia” Kabandana

Area of Doctoral Study: Chemistry
Undergraduate Institute: UMBC

Research Advisor: Chengpeng Chen, Ph.D.

Description of Research

Congratulations, Monia, for winning 1st place in the 2022 G-RISE Three Minute Thesis competition 🎉!

Monia is working on developing 3D printed microfluidics and electrospinning technologies for generating analytical tools that can create 3D cell structures and dynamic environments to mimic the in vivo cell nature. She is specifically aiming to understand cellular behaviors of biofilms and macrophages involved in inflammation.


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Mona Layegh

Area of Doctoral Study: Chemistry
Undergraduate Institute: University of Guilan
Graduate Institute: University of Guilan (M.S. (2012) and Ph.D. (2018))

Research Advisor: Dr. Joseph Bennett and Dr. Zeev Rosenzweig

Description of Research

I am computationally investigating the possibility of fabrication of a specific class of two dimensional materials. These materials are promising candidates in a variety of applications such as energy storage and biomedical.


Kayry Segarra

Area of Doctoral Study: Chemistry
Undergraduate Institute: Stockton University

Research Advisor: William LaCourse, Ph.D.

Description of Research

Stony corals that form calcium carbonate skeletal structures provide a biodiverse habitat for 25% of marine life. Due to an increased frequency of mass coral bleaching events brought on by climate change, preservation and restoration of coral reefs are of critical importance. Coral preservation is a relatively new field, with much of the efforts spearheaded by volunteers and researchers with limited resources, in need of methods for monitoring analytes in seawater. There is still much to learn about how the quality of environmental waters affect overall coral health whether in a tank or in their natural habitat. Quantitation of trace analytes in seawater is complicated by chemical interferences from the high salt content. The purpose of this project is to develop and validate a novel online-sample preparation technique to reduce signal -to-noise ratio for trace analytes in seawater, utilizing strontium ions in seawater as a model.

Cast – Variety Theatre St. Louis

Leopoldo Posada Escobar

Area of Doctoral Study: Chemistry
Undergraduate Institute: University of Texas, Rio Grande Valley

Research Advisor: Zeev Rosenzweig, Ph.D.

Description of Research

MXenes are a new class of two-dimensional nanomaterials, which are composed of alternating atomic layers of a single or a combination of early transition metals and carbide/nitride in a hexagonal crystal lattice. MXenes have a Mn+1XnTx chemical structure where M= early transition metal, X= C and/or N, Tx= surface terminations, and n= 1-4.  The MXene class of nanomaterials have been a prominent research focus since their discovery and some of the compositions exhibit outstanding physiochemical properties, which are comparable or better than other two-dimensional nanomaterials and other classes of materials. As such, MXenes have found use in various applications ranging from supercapacitors in energy storage devices to sensors in biomedical research. My research focuses on the synthesis, surface modification, and characterization of Ti3C2Tx MXene to obtain molecular level understanding of the chemical interactions of the surface-medium interface between MXene and various complex media; as well as biological substrates (i.e., model bacterial organisms like S. oneidensis and B. subtilis). Additionally, my research is focused on developing surface modifications that may help inhibit degradation pathways and improve the physiochemical properties of MXenes in these various media.


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Misti Cartwright

Area of Doctoral Study: Chemistry
Undergraduate Institute: University of Tampa
Graduate Institute: Georgetown University

Research Advisor: Aaron Smith, Ph.D.

Description of Research

My research focuses on the post translational modification, arginylation. I will be studying how the enzyme arginyltransferase allows for this modification to occur.


Alexander Paredes

Area of Doctoral Study: Chemistry
Undergraduate Institute: Gettysburg College

Research Advisor: Aaron Smith, Ph.D.

Description of Research

I am working on a novel two-component signal transduction system, BqsS-BqsR, which has been seen to regulate biofilm formation/decay in Pseudomonas aeruginosa through extracellular ferrous iron binding.  The deletion of either protein gene in Pseudomonas aeruginosa (Pa)results in a significant increase in biofilm formation. However, neither of these proteins have been structurally characterized, and the molecular-level details of how and to what extent either (or both) proteins interact with Fe2+ remains unknown. In my research, I am exploring the structural characterization, the protein structure, and the metal-binding capabilities of this two component system. I am also working on determining critical residues required for metal acquisition, and once I have determined the critical residues for metal binding and signal transduction, I will make mutations in Pa in order to determine the phenotypes of these mutations, especially the ability of this pathogen to form and/or to dissociate biofilms. With sufficient structural information, I will also test a suite of potential compounds that would be designed to target this specific two-component system, in order to aid in the attenuation of Pa virulence.


Lahari Saha

Area of Doctoral Study: Chemistry
Undergraduate Institute: University of Maryland, Baltimore County

Research Advisor: Chris D. Geddes Ph.D.

Description of Research

My research employs a technique called Fluorophore-Induced Plasmonic Current (FIPC) that uses chromophores found in nature like chlorophyll, beta-carotene, and lutein to convert sunlight into electricity.  I have demonstrated this technology with other compounds that are fluorescent for example fluorescein and Texas Red and with inexpensive metals like copper. My goal is to transfer our current understanding to other chromophores and make our system easy to manufacture, inexpensive to buy and maintain, and be able to withstand natural elements. To achieve this, I’ve explored methods such as annealing copper films to generate more current and improve film stability. I significantly increased current responses using gold colloids mixed with the fluorophore solutions. My next steps are to study surface coatings to ensure the longevity of the system and adopt algae for current generation further down the line.

 


Naba Krishna Das

Area of Doctoral Study: Chemistry
Undergraduate Institute: Shahjalal University of Science and Technology
Graduate Institute: Shahjalal University of Science and Technology
Graduate Institute: Mississippi State University

Research Advisor: Deepak Koirala, PhD.

Description of Research

My current research project focuses on determining high-resolution crystal structures of viral RNA domains associated with the cap-independent translation initiation in positive (+)-sense single-stranded (ss) RNA viruses and understanding their functional roles using synthetic antibodies. My projects involve the synthesis and purification of viral RNA constructs as well as the expression and purification of the antibodies – especially the Fab fragments. It also involves characterization of Fab-RNA binding using various molecular biology, biochemical and biophysical techniques and setting up the crystallization trials. Once Fab-RNA crystals are obtained, the diffraction data are collected at Argonne National Lab, and the suitable datasets are used to solve the high-resolution crystal structures.


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Kushani Mendis

Area of Doctoral Study: Chemistry
Undergraduate Institute: University of Kelaniya

Research Advisor: Zeev Rosenzweig, Ph.D.

Description of Research

Fluorescent Semiconducting Polymer dots for Biological Applications


Hasan Al Banna

Area of Doctoral Study: Biochemistry
Undergraduate Institute: University of Dhaka (BSc & MS)
Graduate Institute: North South University (MPH)

Research Advisor: Deepak Koirala, PhD

Description of Research

Investigating the role of structured RNA elements in genome translation of picornaviruses.


Lucia Rodriguez

Area of Doctoral Study: Biochemistry
Undergraduate Institute: Winthrop University

Research Advisor: Michael F. Summers, Ph.D.

 

Description of Research

Characterizing the interactions between the HIV-1 Rev response element and the viral proteins Rev and Gag.


Karndeep Singh

Area of Doctoral Study: Biochemistry
Undergraduate Institute: University of Maryland, Baltimore County

Research Advisor: Michael F. Summers, Ph.D.

Description of Research

eIF4E-Dependent Capture of HIV-1 mRNA by the Cellular Translational Machinery.

 


Trisha De Jesus

Area of Doctoral Study: Chemistry
Undergraduate Institute: Salisbury University

Research Advisor: Katherine Seley-Radtke, Ph.D.

Description of Research

My research focuses on developing “fleximers” which are nucleoside analogs with a flexible scaffold that splits the purine ring into its imidazole and pyrimidine components through varying connections. These structural changes can aid in the drug design of antiviral therapeutics.