Penn Team Creates Stable Vesicles for Time-Released Drug Delivery

One of the defining features of cells is their membranes. Each cell’s repository of DNA and protein-making machinery must be kept stable and secure from invaders and toxins. Scientists have attempted to replicate these properties, but despite decades of research even the most basic membrane structures—known as vesicles—still face many problems when made in the lab. They are difficult to make at consistent sizes and lack the stability of their biological counterparts.

Now, University of Pennsylvania researchers have shown that a certain kind of dendrimer, a molecule that features tree-like branches, offers a simple way of creating vesicles and tailoring their diameter and thickness. Moreover, these dendrimer-based vesicles self-assemble with concentric layers of membranes, much like an onion.

By altering the concentration of the dendrimers suspended within, the researchers have shown that they can control the number of layers, and thus the diameter of the vesicle, when the solution is injected in water. Such a structure opens up possibilities of releasing drugs over longer periods of time, with a new dose in each layer, or even putting a cocktail of drugs in different layers so each is released in sequence.

The study was led by Virgil Percec, P. Roy Vagelos Professor of Chemistry. Also contributing to the study were Shaodong Zhang, Hao-Jan Sun, Andrew D. Hughes, Ralph-Olivier Moussodia and Annabelle Bertin, all members of Percec’s lab, and Professor of Physics and Astronomy Paul Heiney. 

Their study was published in Proceedings of the National Academy of Sciences.

Read the full story here.

Arts & Sciences News

The Power of Penn Arts & Sciences

On April 12, 2018, the Power of Penn Arts & Sciences fundraising campaign was announced by the Board of Overseers. Launched in conjunction with the University’s Power of Penn campaign, it aims to raise $550 million for the School of Arts and Sciences.

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2018 Penn Arts and Sciences Dean’s Scholars

Penn Arts and Sciences has named 20 students from the College of Arts and Sciences, the College of Liberal and Professional Studies, and the Graduate Division as Dean’s Scholars. This honor is presented annually to students who exhibit exceptional academic performance and intellectual promise.

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Joseph Subotnik Named Edmund J. and Louise W. Kahn Term Professor

Joseph Subotnik, Professor of Chemistry, has been named Edmund J. and Louise W. Kahn Term Professor of Chemistry. A theoretical chemist who focuses on electronic processes in the condensed phase, Dr. Subotnik has made key contributions in electronic structure theory, chemical dynamics, and statistical mechanics.

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Two Penn Arts and Sciences Professors Named Guggenheim Fellows

Charles L. Bosk, Professor of Sociology, and Charles Yang, Professor of Linguistics and Computer Science, have been awarded 2018 John Simon Guggenheim Memorial Foundation fellowships.

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Ahmad Family Endowment Supports Penn Global Seminars

Hyder Ahmad, W’90, and his family have made a generous gift to establish the Ahmad Family Endowment for Penn Global Seminars in Arts and Sciences.

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Abraham Nitzan Named Donner Professor of Physical Sciences

Abraham Nitzan, Professor of Chemistry, has been named Donner Professor of Physical Sciences. Nitzan’s research focuses on the interaction of light with molecular systems, chemical reactions in condensed phases and interfaces and charge transfer processes in such environments.

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2018 Teaching Award Recipients Announced

Steven J. Fluharty, Dean of Penn Arts and Sciences, and Paul Sniegowski, Stephen A. Levin Family Dean of the College of Arts and Sciences, have announced the recipients of the 2018 awards for distinguished teaching in the School.

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College Graduation Speakers for 2018 Revealed

Angela Duckworth, G’03, GR’06, Christopher H. Browne Distinguished Professor of Psychology, will address the Class of 2018 at the graduation ceremony for the College of Arts and Sciences on Sunday, May 13, 2018. She will be joined by student speaker Helena von Nagy, C’18.

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Individualized Care Will Become the Standard for Depression Patients

In a new paper for the Annual Review of Clinical Psychology, researchers Robert DeRubeis, Samuel H. Preston Term Professor in the Social Sciences, and Zachary Cohen of Psychology, address precision medicine, also known as customized-care, in the context of treatment for depression.

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Restoring Vacant Lots Reduces Gun Violence and Crime

In cities across the U.S., about 15 percent of land is considered vacant or abandoned. These areas can foster criminal activity, and urban residents, especially those in low-income neighborhoods, often view vacant land as a threat to their health and safety.

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Robert DeRubeis: Samuel H. Preston Term Professor in the Social Sciences

Professor of Psychology Robert DeRubeis has been named the Samuel H.

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