Past Seminars
"From Piedmont Virginia Community College to the
Landes Group at Rice"
Abstract: The Landes Group is comprised of chemists, applied physicists, and
engineers who develop next- generation tools to image dynamics at soft
interfaces at the limit of a single event. Her group devises new methods and
models for controlling macroscale processes such as protein separations and
photocatalysis using this super-resolved chemical knowledge. The group also
uses advanced signal and image processing methods to improve accuracy
and precision in low-signal measurements. Christy’s outreach activities
emphasize the importance of mathematics and computer programming in
our increasingly data-driven world. Her goal for the community is to
underscore our common values despite the expanding need to broaden and
redefine our respective specializations.
Please visit the Landes Research Group to learn more about Dr. Christy Landes and her research.

Wednesday, March 22nd from 6:00-7:30
Jonathan L Sessler | Professor | Biomedical Engineering
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"Texas-Inspired Drug Discovery Efforts"
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This lecture will present the development of expanded porphyrins as potential
drug leads. The presentation will begin with a personal story of a 3x cancer
survivor and how with the assistance of great coworkers and collaborators an
effort has been made to fight back against this disease by studying the
chemistry and anti-cancer biology of gadolinium(III) texaphyrins.
Texaphyrins were the first of the so-called expanded porphyrins--larger
analogues of heme pigments--to stabilize a 1:1 complex with a metal cation.
Subsequently, and continuing as a focus today, an effort has been made in our laboratories and those of many others to create additional expanded porphyrins. Hundreds are now known. Several from our laboratory have proved useful at stabilizing actinide cation complexes.
Recently, efforts have been made to create so-called immunogenic cell death promoters designed to prevent cancer recurrence based on redox-active gold(I) carbenes. An introduction to this new research direction will be included in this lecture, as well new work involving the development of expanded porphyrins and ExJade as
ligands for the lanthanides and actinides.

Thursday, March 9th from 6:00-7:30
Huiliang (Evan) Wang | Assistant Professor |
Biomedical Engineering
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"Ultrasound triggered liposome light source for
noninvasive optogenetics"
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Optogenetics has revolutionized neuroscience understanding by allowing
spatiotemporal control over cell-type specific neurons in neural circuits.
However, visible light cannot be directly delivered to deep brain tissue, due to
the severe dissipation and scattering of photons. As a result, invasive
craniotomy is usually required to implant optical fibers in the brain for in vivo
optogenetic stimulation, resulting in permanent damage and chronic gliosis in brain tissue. To achieve non-invasive optogenetics with high temporal resolution and excellent biocompatibility, we have developed focused ultrasound triggered nanoscopic light sources (Lipo@IR780/L012) for deep brain photon delivery. Synchronized and stable blue light emission was generated under FUS irradiation due to the activation of chemiluminescent L012 via nearby reactive oxygen species generated by IR780. In vitro tests revealed that Lipo@IR780/L012 could be triggered by FUS for light emission at different frequencies and hence activate opsin-expressing spiking HEK cells under the FUS irradiation. In vivo optogenetic stimulation further demonstrated that motor cortex neurons could be
noninvasively and reversibly activated under the repetitive FUS stimulation after i.v. injection of lipid nanoparticles to achieve limb motions control.

Thursday, February 16th from 6:00-7:30
Hang Ren | Assistant Professor | Department of Chemistry
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"Revealing the heterogeneity in metal dissolution reaction via
colocalized electrochemical and structural imaging"
Electrochemical metal dissolution reactions are fundamentally important in
battery and corrosion processes. Their kinetics is highly dependent on surface
structures and the presence of passive films. In this talk, I will present the
study on the initiation of metal dissolution reactions on Ag and Ni,
representing model systems for oxide-free and oxide-covered metals,
respectively. The local dissolution kinetics is voltammetrically mapped via
scanning electrochemical cell microscopy (SECCM). Co-localized characterization of crystal orientation reveals slower dissolution on {111} close-packed planes. The local dissolution kinetics on grain boundaries can also be directly measured, which shows a faster dissolution rate on some but not all grain boundaries. The dependence of passive film breakdown on the thickness of the passive film is also revealed, which is obtained from colocalized TOF-SIMS mapping. We demonstrate that correlative electrochemical and structural imaging are powerful tools for studying heterogeneity at complex electrochemical interfaces.