The Weeks Laboratory invents novel chemical microscopes for understanding the structure and functions of RNA and then applies these unique technologies to leading, and previously intractable, problems in biology. Current projects investigate the basic science of RNA chemistry; meld molecular chemistries with genome-scale readouts of RNA structure; focus on the genome structure and biology of human viruses, especially HIV; and create new therapeutics directed against viruses and human genetic disease. Most projects in the laboratory span fundamental chemistry or technology development and ultimately lead to practical applications in virology, next-generation structure analysis, or understanding biological processes in living cells. Collectively, this work has led to extensive recognition of student and postdoctoral colleagues in the laboratory.
The Waters Group is an interdisciplinary group, focusing on problems of molecular and biomolecular recognition. Molecular recognition impacts a wide range of fields, including asymmetric catalysis, materials chemistry, and protein folding. Consider, for example, designing a drug to bind to the active site of an enzyme. What features other than shape might contribute to binding? What types of interactions will provide high affinity as well as high selectivity? These are general questions in the field of molecular recognition that the Waters Group investigates for applications to biosensing, drug delivery, and de novo protein design.
Joseph Templeton, Francis Preston Venable Professor of Chemistry, and Vice Chair of Education at Carolina Chemistry, has been elected fellow of the American Association for the Advancement of Science, AAAS, the world's largest general scientific society. Professor Templeton is being honored for his scientifically distinguished efforts to advance science and its applications.
New fellows will be honored February 15 at the 2014 AAAS Annual Meeting in Chicago. AAAS is an international nonprofit organization dedicated to advancing science around the world. It publishes the journal Science, as well as newsletters, books and reports.
Congratulations to Professor Joseph DeSimone and former lab members, Jason Rolland and Ben Maynor, winners of the 2014 Kathryn C. Hach Award for Entrepreneurial Success from the American Chemical Society!
The winners will be formally presented with the award during a March 2014 National Awards Ceremony at the ACS National Meeting in Dallas. The award recognizes the team's successful efforts to commercialize the PRINT® technology after it was invented in the DeSimone lab in 2004.
The Journal of Chemical Physics is celebrating its 80th anniversary as the leading and most cited journal in chemical physics. To commemorate the occasion, 80 articles have been selected that highlight the 80 years of outstanding work published. Professor Lee Pedersen's article "Particle Mesh Ewald: N-log(N) Method for Ewald Sums in Large Systems," co-authored by Tom Darden and Darrin York, is one of the highlighted articles.
Coincidentally, 2013 also year marks the 20th anniversary of the publication of this first PME paper, which initiated the use of so-called "Fast Ewald" methods in simulations. The ACS recognized the 20 year event with a two day symposium at a recent national meeting. The use of fast Ewald methods has enabled the simulation of a myriad of molecular systems. In addition it has allowed the accurate treatment of electrostatics at an affordable computational cost
Notably, each of these 20 years, the citations of this article have exceeded those of the year before. With currently more than 7100 citations, this article has enjoyed an unusual and long-lasting interest.
Over the last several decades, fast-scan cyclic voltammetry, FSCV, has proved to be a valuable analytical tool for the real-time measurement of neurotransmitter dynamics in vitro and in vivo. Indeed, FSCV has found application in a wide variety of disciplines including electrochemistry, neurobiology, and behavioral psychology. The maturation of FSCV as an in vivo technique led users to pose increasingly complex questions that require a more sophisticated experimental design. To accommodate recent and future advances in FSCV application, the Wightman Group has developed High Definition Cyclic Voltammetry, HDCV. As described in Analytical Chemistry, HDCV is an electrochemical software suite that includes data acquisition and analysis programs.
The data collection program delivers greater experimental flexibility and better user feedback through live displays. It supports experiments involving multiple electrodes with customized waveforms. It is compatible with transistor–transistor logic-based systems that are used for monitoring animal behavior, and it enables simultaneous recording of electrochemical and electrophysiological data. HDCV analysis streamlines data processing with superior filtering options, seamlessly manages behavioral events, and integrates chemometric processing. Furthermore, analysis is capable of handling single files collected over extended periods of time, allowing the user to consider biological events on both subsecond and multiminute time scales.
Nitric oxide, NO, a reactive free radical, has proven effective in eradicating bacterial biofilms with reduced risk of fostering antibacterial resistance. Published in ACS Applied Materials & Interfaces, researchers in the Schoenfisch Group have evaluated the efficacy of NO-releasing silica nanoparticles against Gram-negative Pseudomonas aeruginosa and Gram-positive Staphylococcus aureus biofilms as a function of particle size and shape.
Three sizes of NO-releasing silica nanoparticles with identical total NO release were utilized to study antibiofilm eradication as a function of size. To observe the role of particle shape on biofilm killing, the group varied the aspect ratio of the NO-releasing silica particles from 1 to 8 while maintaining constant particle volume and NO-release totals. Nitric oxide-releasing particles with decreased size and increased aspect ratio were more effective against both P. aeruginosa and S. aureus biofilms, with the Gram-negative species exhibiting the greatest susceptibility to NO.
To further understand the influence of these nanoparticle properties on NO-mediated antibacterial activity, the group visualized intracellular NO concentrations and cell death with confocal microscopy. Smaller NO-releasing particles exhibited better NO delivery and enhanced bacteria killing compared to the larger particles. Likewise, the rod-like NO-releasing particles proved more effective than spherical particles in delivering NO and inducing greater antibacterial action throughout the biofilm.
Nanoparticle (NP) drug loading is one of the key defining characteristics of an NP formulation. However, the effect of NP drug loading on therapeutic efficacy and pharmacokinetics has not been thoroughly evaluated. Published in Biomaterials, researchers in the DeSimone Group, characterize the efficacy, toxicity and pharmacokinetic properties of NP docetaxel formulations that have differential drug loading but are otherwise identical.
Particle Replication in Non-wetting Templates, PRINT®, a soft-lithography fabrication technique, was used to formulate NPs with identical size, shape and surface chemistry, but with variable docetaxel loading. The lower weight loading (9%-NP) of docetaxel was found to have a superior pharmacokinetic profile and enhanced efficacy in a murine cancer model when compared to that of a higher docetaxel loading (20%-NP). The 9%-NP docetaxel increased plasma and tumor docetaxel exposure and reduced liver, spleen and lung exposure when compared to that of 20%-NP docetaxel.
At the Department of Chemistry, we feel strongly that diversity is crucial to our pursuit of academic excellence, and we are deeply committed to creating a diverse and inclusive community. We support UNC's policy, which states that "the University of North Carolina at Chapel Hill is committed to equality of opportunity and pledges that it will not practice or permit discrimination in employment on the basis of race, color, gender, national origin, age, religion, creed, disability, veteran's status, sexual orientation, gender identity or gender expression."