UWinChem

Monday, January 22, 2018

Seminar: Leah Casabianca (Clemson University) - Friday, Jan. 26, 2018 @ 3:00 p.m.

Seminar: Leah Casabianca (Clemson University)

UWinChemBiochem Seminar Series - Winter 2018

Leah Casabianca
Department of Chemistry
Clemson University, Clemson, SC  
Title: “Characterization of Nanoparticle Surface Interactions Using Dissolution Dynamic Nuclear Polarization and Saturation-Transfer Difference NMR”
Web: https://chemistry.sites.clemson.edu/casabiancagroup/

Friday, Jan. 26, 2018 @ 3:00 p.m.
Room #186 Essex Hall

**Everyone Welcome**





Characterization of Nanoparticle Surface Interactions Using Dissolution Dynamic Nuclear Polarization and Saturation-Transfer Difference NMR
Leah B. Casabianca, Department of Chemistry, Clemson University
Nanotechnology is becoming increasingly prevalent in our everyday lives. Nanoparticles that are used as lubricants, in drug delivery, and as antibacterial agents are finding their way into the body and into the environment, where they interact with biological macromolecules such as proteins. Understanding the nature of the interactions between nanoparticles and adsorbed molecules is therefore increasingly relevant in fields such as drug delivery, nanoparticle catalysis, and nanoparticle toxicity. In this talk, I will discuss several recent studies in my lab that are aimed at developing Nuclear Magnetic Resonance (NMR) techniques for studying noncovalent nanoparticle surface interactions.
NMR is an incredibly powerful characterization technique, capable of providing atomic-level structural as well as dynamic information. However, NMR is not ideally suited for surface studies due to the inherent low sensitivity of this technique. One way of improving the sensitivity of NMR is Dynamic Nuclear Polarization (DNP). DNP relies on the transfer of polarization from a nearby unpaired electron to nuclei of interest in NMR. My group has recently1 developed HighlY-effective Polymer/Radical Beads (HYPR-Beads), which are organic nanoparticles that have been doped with radicals for use as DNP polarization agents. Using HYPR-beads, we were able to hyperpolarize nuclei in small molecules that are located near the beads in an aqueous environment.
We are also using Saturation Transfer Difference (STD)-NMR Spectroscopy to identify small molecules that interact noncovalently with the surface of functionalized organic nanoparticles in solution.2,3 STD-NMR was originally developed to identify small-molecule ligands that bind to a particular protein receptor. Since this technique does not require the receptor to be seen by solution-state NMR, there is no upper limit to the size of the receptor that can be studied. This makes the STD-NMR technique an ideal one to study small molecules adsorbed on the surface of nanoparticles. We have used STD-NMR to determine the binding constant between small molecules and solvent water on the surface of nanoparticles,2 and to determine the binding epitopes of a fluorescent dye associating with the nanoparticle surface.3 This work has future applications in determining the structure of proteins adsorbed on the surface of nanoparticles, and in the development of dual-use imaging contrast agents.
References
[1] Y. Zhang, P. J. Baker, L. B. Casabianca, “BDPA-Doped Polystyrene Beads as Polarization Agents for DNP-NMR.” J. Phys. Chem. B 2016, 120, 18-24.
[2] Y. Zhang, H. Xu, A. M. Parsons, L. B. Casabianca, “Examining Binding to Nanoparticle Surfaces Using Saturation Transfer Difference (STD)-NMR Spectroscopy.” J. Phys. Chem. C 2017, 121, 24678-24686.
[3] Y. Zhang, H. Xu, L. B. Casabianca, “Interaction Between Cyanine Dye IR-783 and Polystyrene Nanoparticles in Solution.” submitted.

Bio: Dr. Casabianca received a B. S. degree in chemistry from Rice University in 2002 where she did undergraduate research with Prof. Seiichi P.T. Matsuda.  She completed her Ph. D. in the lab of Prof. Angel C. de Dios at Georgetown University in 2008.  Her thesis work involved using solution-state NMR and chemical shift calculations to understand the mechanism of action of anti-malarial drugs.  She then did a postdoctoral fellowship (2008-2010) with Prof. Yoshitaka Ishii at the University of Illinois at Chicago working on structural characterization of graphite oxide.  Her second postdoctoral fellowship was in the group of Prof. Lucio Frydman at the Weizmann Institute (2010-2013) where she worked on dynamic nuclear polarization of diamond samples.  She joined the faculty at Clemson University in 2014.

Wednesday, January 17, 2018

Seminar: Caleb Martin (Baylor University) - Friday, Jan. 19, 2018 @ 3:00 p.m.

Seminar: Caleb Martin (Baylor University)

UWinChemBiochem Seminar Series - Winter 2018

Caleb Martin
Department of Chemistry and Biochemistry
Baylor University, Waco, TX
Title: “Exploiting the Diverse Chemistry of Boroles to Access Unsaturated Boracycles”
Web: http://sites.baylor.edu/caleb_d_martin/

Friday, Jan. 19, 2018 @ 3:00 p.m.
Room #186 Essex Hall

**Everyone Welcome**


Friday, January 12, 2018

Seminar: Jeff Reimer (University of California at Berkeley) - Tuesday, Jan. 16, 2018 @ 3:00 p.m.

Seminar: Jeff Reimer (University of California at Berkeley)

UWinChemBiochem Seminar Series - Winter 2018

Jeff Reimer
Department of Chemistry
University of California at Berkeley 
Title: “Why, and How, I would like to Decarbonize our Air”
Web: https://chemistry.berkeley.edu/faculty/cbe/reimer

Tuesday, Jan. 16, 2018 @ 3:00 p.m.
Room #109 Essex Hall

**Everyone Welcome**
**Note the special room***



Tuesday, January 9, 2018

Summer Research for Undergrads! NSERC USRA Applications Due Jan. 22, 2018

Summer Research for Undergrads!  NSERC USRA Applications Due Jan. 22, 2018

NSERC – USRA SCHOLARSHIPS

DEPARTMENT OF CHEMISTRY & BIOCHEMISTRY DEADLINE – MONDAY, JANUARY 22, 2018

- Official transcripts required (Wait until January to request one so the Fall grades appear)

- All printed application material must be submitted to Marlene Bezaire, room #273-1 Essex Hall no later that Monday, January 22, 2018

For more information, please click here!

or visit: http://www1.uwindsor.ca/chemistry/summer-research




Sunday, January 7, 2018

Seminar: Andre Simpson (Department of Chemistry, University of Toronto, Canada) - Friday, Jan. 12, 2018 @ 3:00 p.m.

Seminar: Andre Simpson  (Department of Chemistry, University of Toronto, Canada)


UWinChemBiochem Seminar Series - Winter 2018
André J. Simpson
Friday, Jan. 12, 2018 @ 3:00 p.m.
**Everyone Welcome**


Department of Chemistry
University of Toronto 
Title: “From Structure to Interactions to In vivo NMR: The vast potential of NMR Spectroscopy in Environmental Research”
Web: http://www.utsc.utoronto.ca/~asimpson/

Room #186 Essex Hall







Abstract:


NMR spectroscopy is arguably the most powerful tool for elucidating structures and probing molecular interactions. Practically all environmental research, at least to some extent, involves working with ultra-complex natural mixtures that are ubiquitous in soil, water, and air. NMR can provide information not only as to the basic chemical structures present in a mixture, but can potentially provide information as to the self-associations of molecules (aggregation and flocculation processes), their mechanistic interactions with xenobiotics (transport of contaminants) and provide the direct connection between molecular scale processes (environments of individual nuclei) and macroscopic scale (visual), in the form NMR imaging. 

This presentation will take the audience through an evolution of my career from molecular-structure at one extreme to the impact of chemicals in living systems at the other.

Structure: Understanding the structure of soils, air particles, and dissolved organic is a critical precursor to understanding how these materials function. This information is desperately needed to develop the most efficient soil remediation and agricultural practices as-well as better predict carbon sequestration and climate change.

Interactions: With a better understanding as to the structural components and NMR assignments for key environmental matrices it is then possible to determine, how, where, and why contaminants get sequestered and are challenging to remediate. A range of novel NMR experiments will be introduced along with a new technology termed comprehensive multi-phase NMR. Comprehensive Multiphase (CMP) NMR, was co-developed between my group and Bruker Biospin. The approach combines all the electronics from solution-state, semi-solid and solid-state NMR into a single NMR probe. The resulting technology permits an uncompromised analysis of liquid, semi-solid and solid components within unaltered samples in their natural swollen state. As well as unravelling the binding orientation, and receptors for contaminants/drugs CMP-NMR is also capable of monitoring the kinetic transfer between and across interfaces providing an unprecedented window into otherwise inaccessible molecular information.

Impact: With an understanding as to “what soil is?” and “which chemical components bind contaminants?" the key questions become “what does it all mean?” and “how are living systems impacted?”. For example, if a herbicide is bound tightly to the protein fraction of soil is it still bioavailable? Would this still hold true with climate change or change in land use? An even more challenging but important question is “out of the 100’s or 1000’s chemicals we are exposed to everyday which ones truly impacts our health?” Indeed similar questions are asked everyday by policy makers. NMR has great potential to address such challenges when employed as the “molecular interpreter” of living systems under environmental stress. In this final section in-vivo NMR is introduced on small invertebrates. Static studies (i.e. using a flow system and solution-state probes) provide a low stress environment to study metabolic flux in response to stressors. Conversely, CMP-NMR, can potentially be used to study and differentiate different phases (liquids (metabolites), gels (proteins, membranes), solids (shell, bone)) in-vivo. A wide range of novel experiments will be introduced that greatly improve the depth and breadth of information that can be obtained from NMR of living systems. Combined the approaches hold the potential to identify which are the most potent environmental stressors in complex natural samples, explain their toxic-mode-of-action and even act as early warning system to identify environmental stress, prior to disease, or ecosystem shifts. 




         

Wednesday, January 3, 2018

You should hire an undergrad for your lab - by Prof. John Trant

You should hire an undergrad for your lab
Undergraduate colleagues make you a better researcher and teacher. Here’s how.
By JOHN TRANT | DEC 29 2017

Read Prof. John Trant's article at the University Affairs web site!

https://www.universityaffairs.ca/opinion/in-my-opinion/hire-undergrad-lab/




Seminar: Amy Szuchmacher Blum (McGill University) - Friday, Jan. 5, 2018 @ 3:00 p.m.

Seminar: Amy Szuchmacher Blum (McGill University)

UWinChemBiochem Seminar Series - Winter 2018

Amy Szuchmacher Blum
Department of Chemistry
McGill University
Title: “Making viruses work for us: self-assembled nanostructured materials”
Web: http://www.mcgill.ca/chemistry/faculty/amy-blum

Friday, Jan. 5, 2018 @ 3:00 p.m.
Room #186 Essex Hall

**Everyone Welcome**