Seminars & Events

Throughout the academic year, the department hosts several seminars whose presenters range from department graduate students to internationally renowned professors and scientists. The calendar below includes all of our department seminars and events. It is updated frequently with titles and abstracts — you can subscribe using Google Calendar by clicking the "+GoogleCalendar" button in the lower right. 

Seminars

Friday Colloquium Series

Faculty members and graduate students invite professors from other institutions throughout the country and the world to speak at Brown on a Friday afternoon. Friday colloquiua topics span the various fields of chemistry represented by the department. Sometimes, a colloquium seminar is hosted jointly with another department or institute, such as IMNI, the Institute for Molecular and Nanoscale Innovation. Friday afternoons, 4:00pm - 5:00pm, MacMillan Hall 115. Refreshments served at 3:45pm.

Organic Chemistry Seminars

Organic chemistry graduate students are required to give at least two seminars. The first is a literature seminar on a topic of recent interest, and the second is the candidate's thesis research. Invited guests frequently present their research at Organic Seminars as well. Tuesday afternoons, 12:00pm - 1:00pm, GeoChem 351.

Inorganic Chemistry Seminars

Inorganic chemistry graduate students are expected to present one seminar per year on their own research or on another topic of current interest in inorganic chemistry. Research associates, faculty and invited guests often present inorganic seminars as well. Thursday afternoons, 12:00pm - 1:00pm, GeoChem 351.

Physical Chemistry Tea Sessions

Physical chemistry graduate students are expected to present one seminar per year. Topics covered include the graduate students' topics of interest with regard to current research, as well as their own research. Thursday afternoons, 3:00pm - 4:00pm, GeoChem 349/351. Light refreshments served at 2:45pm. 

   

Upcoming Events

  • Abstract: In recent years organic semiconductors have evolved from academic curiosities, to functional materials for use in a variety of areas including energy (solar cells), displays, (light emitting diodes), electronics (field effect transistors), and life sciences (sensors). Organic semiconductors have been proclaimed as materials that combine the processing properties of polymers with the optical and electronic properties of conventional semiconductors. These carbon-based small molecules, oligomers or polymers offer several advantages over inorganic materials including: 1) the ability to tune their energy levels, solubility and thermal stability through chemical synthesis, allowing for the optimization of these parameters; 2) the ability to be fabricated using solution-processing, reducing the cost of production; 3) the possibility to produce devices on flexible substrates for use on curved or uneven surfaces; and 4) the ability to synthesize a large amount of materials under moderate conditions. Although there are a large number of synthetically accessible organic semiconductors, there are still several issues to be addressed on for the large –scale manufacture of “plastic” electronics to become a reality. Some challenges include, scalability of the chemical synthesis, elimination of defects within the materials and improvements in mechanical toughness. Our group focuses on the design and synthesis of both polymeric and molecular organic semiconductors based from low cost and/or easily prepared starting materials. To date, we have produced a number of new materials for use in various semiconducting applications. Our work on the synthesis and properties and utility of these materials will be presented.

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  • Cells use various mechanisms to organize reactions and sequester proteins, RNA, and chromatin for transcription, processing, and localization. One emerging mechanism is liquid-liquid phase separation mediated by the association of the disordered domains of RNA binding proteins. RNA-binding proteins FUS, TDP-43, and hnRNPA2 are all associated with RNA granule assembly and all form inclusions in amyotrophic lateral sclerosis and multisystem proteinopathy, respectively. Using these proteins as models, we probe their molecular structure along the assembly pathway and the structural changes caused by disease mutations and post-translational modifications. Using nuclear magnetic resonance (NMR) spectroscopy and molecular simulation, we see their structure and interactions with atomic resolution. These findings are paired with microscopy and turbidity experiments and cell assays to assess the effect of post-translational modifications and mutations on phase separation, aggregation, toxicity and splicing function. We find that low complexity domains remain predominantly unstructured both before and after phase separation. The exception is TDP-43 where phase separation and protein function is enhanced by a globular domain and an alpha-helical region whose helical extent increases and extends upon phase separation. Arginine methylation and phosphorylation disrupts phase separation, aggregation, and cellular toxicity. Our work points to the potential for post-translational modification to alter assembly, function, and pathological interactions of disease-associated disordered domains.

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  • Abstract: Plasmonic nanoantennas are attractive for a variety of potential applications in nanotechnology, biology, and photonics due to their ability to tightly confine and strongly enhance optical fields. In recent years, our group, the PROBE Lab, has made significant contributions in plasmonic nanoantenna technology by more closely exploring the rich parameter space associated with these structures. This talk will discuss our work with arrays of Au bowtie nanoantennas (BNAs) with an emphasis on harnessing their field enhancement properties for improved manipulation of microparticles. In addition, we will present some unique features of BNAs when they are supported on high-aspect ratio pillars. Aside from the particle manipulation features that these pillar-supported BNAs (pBNAs) share with their substrate-bound counterparts, the use of pBNAs to record the optical near field and create planar optical elements will also be discussed. The talk will conclude with a discussion of some future prospects for nanoantenna technology.

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  • Abstract: Our lab specializes in the chelation of lanthanides and transition metals in aqueous solutions in the context of radiometal-based tracer development. Efforts in our lab are focused on Sc(III) and Lu(III) coordination chemistry and speciation. We develop chelators for the kinetically inert and biocompatible chelation of these oxophilic, hydrolytic Lewis acids with the goal to deliver the radioactive isotopes Sc-44 and Lu-177 to cancer cells without premature dissociation or deposition of the isotope in off-target tissues. We have established a small-cavity chelator with ideal properties for Sc-44 and Lu-177. Our studies range from using heteronuclear NMR, variable mass spectrometry and pair distribution function analysis of X-ray scattering data to characterize non-radioactive coordination complexes to successful application of the radioactive isotopes for targeted imaging and therapy of prostate cancer in mice.

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  • Mar
    13
  • Apr
    17
  • The recent surprising discovery of the salutary effects of low doses (50-200 ppm) of carbon monoxide (CO) in diseases like pulmonary arterial hypertension, COPD, and arterial wall lesions from balloon angioplasty has initiated intense research effort toward exploration of the therapeutic benefits of this so-called toxic gas. Results of such studies have also indicated that moderate doses (>250 ppm) of CO causes rapid reduction of cancer cells (but not normal cell) through cell apoptosis via disruption of mitochondrial function. In addition, CO dramatically sensitizes cancer cells to chemotherapy and imparts antiproliferative effect toward colon, breast, ovary, pancreas, and other cancers. Because of its toxic nature, it is however difficult to employ gaseous CO in hospital settings. We have recently shown that photoactive and biocompatible metal carbonyl complexes with designed ligands can deliver suitable doses of CO to cellular targets under the total control of light. In addition we have shown that these photosensitive CO-releasing molecules (photoCORMs) can be conveniently used to kill human breast and colon cancer cells in a dose-dependent manner through light-induced CO release. Recently we have been successful in incorporating several fluorescent photoCORMs within the pores of silica nanoparticles (SNPs) and have demonstrated (a) their accumulation within cancer cells, (b) fluorescence tracking of the process of CO delivery within the cancer cells, and (c) their eradication by a dose-dependent CO photo delivery. Results from these experiments as well their promise in translation to animal models will be discussed.

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  • May
    1