Calendar

Mar
28
Thu
2024
Molecular Scale Engineering of Polymer Membranes for Environment, Energy and Health
Mar 28 @ 12:00 pm – 1:00 pm
Molecular Scale Engineering of Polymer Membranes for Environment, Energy and Health @ Zoom webinar

Assistant Professor Hee Jeung Oh of Penn State University will present a free webinar on novel, solvent-free methods for preparing semipermeable membranes used in water purification and time-release pharmaceutical applications.

Abstract

Designing new polymer membranes with a set of previously unachievable transport properties will have an enormous impact on various applications, including energy-efficient separations, energy storage and health-related devices. The advancement of these technologies is dependent on polymer membranes which selectively transport only desired penetrants while maintaining chemical stability. Molecular transport in polymer membranes is greatly influenced by the chemical and morphological structures of polymers. Here two research projects are presented for designing new membranes using charged polymers for improved molecule separations. The transport mechanism in the polymer membranes is studied from the fundamental perspectives of polymer-penetrant interactions and templating diffusion pathways for selective transport of small molecules.

First, solvent-free, melt processed ion-exchange membranes based on sulfonated polymers are presented for water purification and desalination. Most membranes currently used in industry are prepared by solvent processing using large volumes of hazardous solvents. Despite the negative environmental impact, solvent processing is the only method to form thin film membranes on the order of 10-200 nm thickness. In stark contrast to conventional solvent processing, robust ion-exchange membranes based on sulfonated polymers were prepared by solvent-free melt processing, for the first time. The transport of small molecules in resultant membranes is significantly affected by different membrane formation methods.

Second, designing nanostructured polymer membranes for a new emerging biomedical application, “drug capture”, to minimize the toxic side effects of cancer chemotherapy drugs, is discussed. Typically, more than 90% of the injected drug is not trapped in the target organ, causing systemic toxic side effects. We designed 3D printed biosponge absorbers for capturing toxic drugs downstream of tumors before they spread through the body.

Hee Jeung Oh

Hee Jeung Oh is an Assistant Professor of Chemical Engineering and Materials Science and Engineering at Penn State University. The Oh lab designs multifunctional polymer membranes for separations. Specifically, the Oh lab studies the relationship between polymer chemistry, processing, structure, and transport properties for separation science, and explores the influence of a polymer’s chemical and physical structures on transport properties such as sorption, diffusion, permeation, and conduction of small molecules in polymers and polymer-based materials. These fundamental studies are critical for designing membranes for liquid, gas and vapor separations, energy storage, selective removal of unwanted molecules from various chemical streams, selective recovery of critical and precious elements, biomedical devices, controlled drug-delivery, and barrier materials for food and packaging. Dr. Oh earned her B.S. in Chemical Engineering from the Korea Advanced Institute of Science and Technology (KAIST). Dr. Oh completed her Ph.D. in Chemical Engineering working in Drs. Benny Freeman’s and Donald Paul’s research groups at the University of Texas at Austin, exploring a variety of polymeric materials for membrane-based separation, with a particular emphasis on membranes for water purification, and focusing on transport of small molecules such as water and ions in polymer membranes. Dr. Oh first developed solvent-free, melt-processed, robust ion-exchange membranes based on sulfonated polymers, and evaluated water and salt permeation, sorption, and diffusion in the membranes. Her postdoctoral training, working in Dr. Nitash Balsara’s research group at UC Berkeley, focuses on designing porous nanostructured polymers for energy storage, as well as a new emerging biomedical application, “drug capture,” to minimize toxic side effects of cancer chemotherapy drugs. She first designed and developed a 3D printed absorber for capturing chemotherapy drugs downstream of tumors before they spread through the body and cause the toxic side effects. Dr. Oh has been recognized in honors and awards including 3M Non-Tenured Faculty Award, Young Membrane Scientist Award from the North American Membrane Society (NAMS), Hanwha Non-Tenured Faculty Award, and the University of Texas Professional Development Award. She was invited to National Academy of Engineering (NAE)’s Grainger Foundation Frontiers of Engineering (FOE) Symposium and was selected as one of the two recipients of the National Academy of Engineering (NAE)’s Grainger Foundation Frontiers of Engineering (FOE) grants in 2023.

Apr
20
Sat
2024
Earth Day at the John Muir Historical Site
Apr 20 @ 10:00 am – 4:00 pm

John Muir Association logo

Celebrating John Muir’s 186th birthday
and the 54rd Anniversary of Earth Day

Cal ACS will be there with hands-on chemistry, featuring the 2024 Earth Week theme,

Get a Charge out of Chemistry
Recárgate con la Química

The California Section will join numerous other community and educational organizations for the return of this Earth Day celebration to Martinez.  Look for the Cal ACS canopy, where visitors will discover how to build a battery like the one Alessandro Volta invented in 1799.  They can also try splitting water by electrolysis, using electricity from photovoltaic panels.  And, they can make their own UV light-detecting bracelet using photochromic beads.

If you can help out at the ACS booth, please contact Sushila Kanodia.  See you there!

Apr
22
Mon
2024
Professor Jennifer Doudna: “How Bacteria Taught Us to Cure Genetic Disease”
Apr 22 @ 12:00 pm – 2:30 pm
May
4
Sat
2024
Got Fakes? Paper microfluidics and the hunt for bad quality medicines
May 4 @ 10:30 am – 12:00 pm

Marya Lieberman, PhD

Our Distinguished Speaker

Abstract

In low- and middle-income countries, about one in ten medicine products is substandard or falsified. In my lab, I have samples of antimalarial drugs made from starch and chalk, antibiotics “cut” with talcum powder, and chemotherapy drugs that were manufactured at half the concentration they should have been. How do these products get into the supply chain, and more importantly, how can chemists help to get them out? This talk will focus on a point-of-use testing device that my group invented twelve years ago, the paper analytical device or PAD. I’ll explain how this paper microfluidic device works and how we are implementing it with partners in sub-Saharan Africa to discover bad quality medicines.

About The Speaker

Dr. Marya Lieberman enjoys making stained glass, cooking, and solving fiendish cryptic crosswords. She loves chemistry so much she did a chemistry demonstration at her wedding. As a kid in Berkeley, California, she missed all the exciting stuff in the 60’s and 70’s, although her mother tells her she was gassed in her stroller. She developed an interest in science that was deepened and focused by an undergraduate degree in chemistry at MIT and a PhD from the University of Washington, Seattle, where she designed and built an artificial metalloprotein. A high point in this project was finally understanding her protein’s energy landscape; a low point was sleeping on the floor of the lab during the marathon HPLC kinetics runs required to get to the energy landscape. She received a prestigious NSF Postdoctoral Fellowship to study at Caltech, where she discovered that the NSF had not considered that Fellows might get pregnant and had no maternity leave policy. After the birth of her first child, she and her husband became faculty members at the University of Notre Dame, where they have happily occupied neighboring offices for 28 years. Her second child was born the day before she received tenure. For most of her career, she studied DNA nanostructures and cool molecular electronics with high-vacuum instrumentation and scanning probe microscopes. She took pictures of single molecules sitting on surfaces, knitted DNA into tiny carpets, and studied quantum-dot cellular automata. In 2012, she started a new research program using paper microfluidics to develop technologies for use in low resource settings. For the past 12 years, she has been on the hunt for substandard and falsified medicines with collaborators in Kenya, Tanzania, Malawi, Ethiopia, Cameroon, Palestine, and Bangladesh. This work received coverage by numerous news outlets, including Bloomberg News, Chemical and Engineering News, the Voice of America, and BBC Worldwide.

Zoom link to be shared with attendees the day of the event.

Please register before Thursday, May 2, 2024, 12 noon. Your email address is needed to send the Zoom link, which will be shared with attendees on or before the day of the event via Brown Paper Tickets.

Please visit the CalACS website www.calacs.org to register for this meeting or use Brown Paper Tickets.

The event is FREE and open to the community. More information: e-mail WCC co-chair Elaine Yamaguchi.