Boning Tong, a student in the Department of Bioengineering, has been awarded the Distinguished Paper Award from the AMIA 2024 Annual Symposium. The Awards Committee recognizes five notable papers that best encapsulate the potential of tremendous breakthroughs in the medical community. Ms. Tong works in the laboratory of Dr. Li Shen, who acts as her doctoral advisor and is a professor of Informatics in Biostatistics and Epidemiology.
“Our research tackles challenges in early Alzheimer’s Disease detection by addressing diagnosis label imbalances and fairness issues simultaneously in machine learning models,” said Ms. Tong. “Unlike traditional models, our approach achieves better prediction performance while minimizing bias related to sensitive factors like race, sex, and age. This advancement holds promise for improving the reliability and fairness of early AD detection, ultimately aiding better patient outcomes and equitable care.”
In the future, Ms. Tong plans to take the research they have gained and use them to obtain greater amounts of data. “Our plan is to apply our proposed model to other datasets with larger sample size and more detailed attribute subgroup information to explore the bias issue in AD further,” said Ms. Tong.
Ms. Tong’s work was supported by NIH grants and the ADNI data sets were obtained from the Alzheimer’s Disease Neuroimaging Initiative Database.
Alex Hughes, Assistant Professor in Bioengineering, holds a model of a developing kidney. (Credit: Bella Ciervo)
To Alex Hughes, Assistant Professor in Bioengineering within Penn Engineering and in Cell and Developmental Biology within Penn Medicine, the kidney is a work of art. “I find the development of the kidney to be a really beautiful process,” says Hughes.
Most people only ever see the organ in cross-section, through textbooks or by dissecting animal kidneys in high school biology class: a bean-shaped slice with lots of tiny tubes. “I think that really undersells how amazing the structure is,” says Hughes, who points out that kidneys grow in utero like forests of pipes, branching exponentially.
Densely packed with tubules clustered in units known as nephrons, kidneys cleanse the blood, maintaining the body’s fluid and electrolyte balance, while also regulating blood pressure. The organ played a crucial role in vertebrates emerging from the ocean: as one paper puts it, kidneys preserve the primordial ocean in all of us.
Unfortunately, kidneys struggle in the modern world. Excessively salty food, being overweight, not exercising enough, drinking too much and smoking can all raise blood pressure, which damages the kidney’s tiny blood vessels, as does diabetes.
In some cases, damage to the kidney’s nephrons can be slowed with lifestyle changes, but, unlike the liver, bones and skin, which can regrow damaged tissue, kidneys have a limited capacity to regenerate. At present, without a transplant, the nephrons we have at birth must last a lifetime.
A hyperlink network from English Wikipedia, with only 0.1% of articles (nodes) and their connections (edges) visualized. Seven different reader journeys through this network are highlighted in various colors. The network is organized by topic and displayed using a layout that groups related articles together. (Image: Dale Zhou)
At one point or another, you may have gone online looking for a specific bit of information and found yourself “going down the Wiki rabbit hole” as you discover wholly new, ever-more fascinating related topics — some trivial, some relevant — and you may have gone so far down the hole it’s difficult to piece together what brought you there to begin with.
According to the University of Pennsylvania’s Dani Bassett, who recently worked with a collaborative team of researcher to examine the browsing habits of 482,760 Wikipedia readers from 50 different countries, this style of information acquisition is called the “busybody.” This is someone who goes from one idea or piece of information to another, and the two pieces may not relate to each other much.
“The busybody loves any and all kinds of newness, they’re happy to jump from here to there, with seemingly no rhyme or reason, and this is contrasted by the ‘hunter,’ which is a more goal-oriented, focused person who seeks to solve a problem, find a missing factor, or fill out a model of the world,” says Bassett.
In the research, published in the journal Science Advances, Bassett and colleagues discovered stark differences in browsing habits between countries with more education and gender equality versus less equality, raising key questions about the impact of culture on curiosity and learning.
Dani S. Bassett is the J. Peter Skirkanich Professor at the University of Pennsylvania with a primary appointment in the School of Engineering and Applied Science’s Department of Bioengineering and secondary appointments in the School of Arts & Sciences’ Department of Physics & Astronomy, Penn Engineering’s Department of Electrical and Systems Engineering, and the Perelman School of Medicine’s Departments of Neurology and Psychiatry.
Sam Preza, a doctoral student in Bioengineering, was named one of two Penn graduate students and one of 50 graduate students nationwide to receive a 2024 Howard Hughes Medical Institute (HHMI) Gilliam Fellowship. The HHMI Gilliam Fellowship cohort is awarded annually to graduate students and their advisors for outstanding research and commitment to advancing equity and inclusion in science. The fellowship includes a one-year mentorship skills development course and support to promote healthy and inclusive graduate training environments at their home institution.
Preza is a member of lab of Juan Rene Alvarez Dominguez, Assistant Professor of Cell and Developmental Biology in the Perelman School of Medicine and member of the Bioengineering Graduate Group. He graduated from University of Maryland in 2019 with a degree in Chemical Engineering. After working for t three years at AstraZeneca in Bioprocess Development, he joined the J-RAD Lab where he researches technologies for unmet medical needs:
“[Preza’s] PhD program harnesses the power of stem cells and circadian rhythms to ultimately develop a cure for Type I diabetes, which he researches alongside his advisor, Juan Alvarez, PhD, an assistant professor in the Department of Cell and Developmental Biology. Their studies focus on beta cells, the type of cell found in the pancreas that helps regulate glucose. In the lab, they study how exposing cells to circadian rhythms could lead to functional beta cells that can be transplanted into diabetic patients to restore function. This work will be supported by their HHMI Fellowship grant.
The fellowship not only supports their scientific research but also helps foster an inclusive research environment, ensuring various backgrounds and ideologies contribute to their research. Preza is starting a DEI ‘potluck’, where bioengineering students can gather to discuss new research or career ideas. The meetups are catered by whichever student is hosting the meeting and can either showcase their nationality’s food or a cuisine they are passionate about, highlighting the celebration of diversity of ideas through food.
‘I believe STEM fields should look more like a mosaic of all our backgrounds rather than a melting pot, to add to the richness that is the art of science,’ Preza said.”
Students learn about bioengineering in the BE Labs at the inaugural BETA Day (credit: Felice Macera)
Last year marked not just the 50th anniversary of the Department of Bioengineering (BE) but the 10th anniversary of Bioengineer-Teach-Aspire (BETA) Day, one of the most beloved and impactful programs run by the Graduate Association of Bioengineers (GABE).
BETA Day, an annual event in which a diverse group of Philadelphia middle school students learns about bioengineering and a variety of science, technology, engineering and math (STEM) fields from BE graduate students, has grown into an institution, one whose impact no one could have foreseen.
GABE’s original goal was to provide social opportunities for BE graduate students. While this is still an important function of the group, in the mid-2010s, students and board members found themselves looking for opportunities to provide more formalized outreach and mentorship. They wanted to have an impact on Philadelphia and cultivate the next generation of bioengineers.
The Seeds of BETA Day
Benjamin Freedman, a principal investigator at Beth Israel Deaconess Medical Center, Assistant Professor of Orthopedic Surgery at Harvard Medical School, and founder of biotech startup Limax Biosciences, earned his doctorate in Bioengineering in the lab of Louis Soslowsky, Fairhill Professor in the Department of Orthopaedic Surgery within the Perelman School of Medicine (PSOM) and in Bioengineering within the School of Engineering and Applied Science (Penn Engineering). Freedman played a key role in BETA Day’s founding.
In 2009, Freedman, then an undergraduate at the University of Rochester, attended a talk at the City College of New York (CCNY), which sparked his interest in mentorship. Sheldon Weinbaum, a Distinguished Professor in Biomedical and Mechanical Engineering at CCNY and the Biomedical Engineering Society (BMES) inaugural diversity award winner, spoke about “fulfilling the dream” of mentorship and the struggle for inclusion in STEM fields, echoing the language of Martin Luther King Jr.
Inspired by this encounter, Freedman got involved with a mentorship program during his senior year. He later signed up for a lunch with Weinbaum to talk about mentorship. Freedman recalls that Weinbaum’s face “lit up” when he realized that this student didn’t just want to talk science but was genuinely interested in inclusion, diversity and mentorship.
Arriving at Penn Engineering and PSOM for graduate school in 2011, Freedman joined GABE, bringing this passion and experience with him and helping GABE to shape and clarify their outreach and mentorship programs.
From Campus to Community
Along with other GABE board members, such as Cori Riggin and Shauna Dorsey, Freedman worked over the course of a year and a half to identify the mentorship needs within BE and gauge student interest. David Meaney, Solomon R. Pollack Professor and then Chair of BE, and former BE faculty Susan Margulies, now Professor in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University, were particularly involved in these discussions.
Benjamin Freedman (left) addresses the first BE mentoring cohort (credit: Felice Macera)
The GABE board reorganized to include mentorship and outreach chairs, and eventually started a formal mentorship program in partnership with the Penn undergraduate Biomedical Engineering Society (BMES). The mentorship program continues to this day, creating opportunities for BE graduate students to engage with undergraduate concerns through one-on-one meetings to discuss career or graduate school advice, summer BBQ’s, roundtable discussions and monthly meetups.
With an internal mentorship program established, the team turned their focus to Philadelphia. Initially, GABE established a partnership with iPraxis, a local STEM education non-profit, to do some outreach activities in middle schools. This partnership resulted in an Outstanding Outreach Award from the national Biomedical Engineering Society in 2014. But with the department’s 40th anniversary approaching, GABE’s members wanted to do something spectacular to celebrate and give back to the community.
Service Learning in Action
By then, Ocek Eke, Director of Graduate Students Programming at Penn Engineering, had been recently appointed Director of Global and Local Service Learning Programs. Eke provided Freedman and GABE advice on setting up effective outreach programs and to determine what resources the School could contribute. “We have a role to play to fulfill our mission,” Eke says, citing Penn’s motto, “Leges Sine Moribus Vanae,” which translates to “Laws without morals are useless.”
GABE’s efforts were part of a “wave” of interest in outreach and community service in both the department and the School, Eke remembers, including the undergraduate group Access Engineering and several service learning courses which took students to Asia, Africa and Central America. He was impressed by the lack of cynicism in the BE student body. “These are students who saw a need, who are passionate about what they want to achieve. They could have just been comfortable but were willing to go and stick their necks out. They used the resources we have here in Penn Engineering to address these needs.”
A (BETA) Day to Remember
The first BETA Day took place at the Singh Center for Nanotechnology, which had only just opened. Held with the enthusiastic participation of around 70 middle schoolers, and almost as many volunteers, the event included a full day of programming, with representation from every Penn Engineering department. There were science talks, workshops, and even a drone demo with Vijay Kumar, Nemirovsky Family Dean of Penn Engineering. The entire day was student-driven and staffed by volunteers, demonstrating the students’ commitment to making a difference.
The first annual BETA Day was held in the Singh Center for Nanotechnology (credit: Felice Macera)
GABE never imagined BETA Day as an annual event, but the first instance was so successful, it became hard to imagine not repeating it. Ten years later, the GABE board continues to introduce bioengineering to a diverse and ambitious group of middle schoolers every spring.
In 2021, during the COVID-19 lockdown, the industrious and creative GABE board even tailored BETA Day activities to be held in an entirely virtual environment. “These types of events are not as successful when they’re only initiated by faculty,” says Freedman. Generating and sustaining student involvement has been a cornerstone of BETA Day’s continued success.
The Legacy of BETA Day
GABE’s mentorship efforts have grown as well, changing to meet evolving student needs. The mentorship program now involves students being placed in “families” of around four undergraduates and two graduate students, spanning a range of class years and experience levels. A third student association, the Master’s Association in Bioengineers (MAB), was established to better foster community and facilitate opportunities for master’s students.
The department also launched an applicant support program in 2020, enhancing BE’s mission of increasing diversity, equity and inclusion by pairing Ph.D. applicants to current doctoral students, who serve as mentors to help navigate the admissions process, giving feedback on application materials and providing other support to prospective students.
Structures of support and outreach activities like BETA Day have become a key emphasis of the department’s graduate student recruitment, helping to attract students who value the department’s core mission and increasing opportunities for underserved or underrepresented communities.
The legacy of that original BETA Day also continues in Freedman’s Lab. After graduating in 2017, having served on the GABE board and as President from 2015-2016, Freedman continued to mentor over 20 students during his postdoctoral research at Harvard. He is now building his own independent lab where diversity, mentorship and outreach are foundational pillars.
A Nebula of Inspiration
Perhaps the most consequential impact of BETA Day is the impression it makes on the middle schoolers who participate each year. “To really get to know what happens on BETA Day and what it’s true impact is, you need to experience it,” says Ravi Radhakrishnan, Herman P. Schwan Chair of the Department of Bioengineering and Professor in Bioengineering and in Chemical and Biomolecular Engineering.
The legacy of BETA Day continues into its second decade. (credit: Afraah Shamim, BE Labs)
“I walked into the Stephenson Foundation Education Lab during BETA Day 2024,” recalls Radhakrishnan, “and what I saw was teams of teenagers tinkering with pipes that were clogged, strategizing on unclogging them without damaging them: an assignment that got them thinking in teams about how to prevent heart attacks.
“Expose these young minds to design thinking, versatile tools, and critical problems in biomedical engineering, and the elegant solutions they brainstorm are truly mind blowing. BETA Day is like the nebula where future biomedical stars are born.”
In a collaborative interdisciplinary study, Michael Mitchell of the School of Engineering and Applied Science, Wei Guo of the School of Arts & Sciences, and Drew Weissman of the Perelman School of Medicine show that solid tumors can block drug-delivery mechanisms with a “forcefield-like” effect but certain genetic elements that can effectively “shut down” the forcefield. Their findings hint at new targets for delivering cancer treatments that use the body’s immune system to fight tumors. (Image: iStock / CIPhotos)
The tumor microenvironment—an ad hoc, messy amalgamation of signaling molecules, immune cells, fibroblasts, blood vessels, and the extracellular matrix—acts like a “powerful security system that protects solid tumors from invaders seeking to destroy them,” says Michael Mitchell, a bioengineer at the University of Pennsylvania working on nanoscale therapeutics aimed at targeting cancers.
“A lot like the Death Star with its surrounding fleet of fighter ships and protective shields, solid tumors can use features like immune cells and vasculature to exert force, acting as a physical barrier to rebel forces (nanoparticles) coming in to deliver the payload that destroys it,” Mitchell says.
Now, researchers in the Mitchell lab have teamed up with Wei Guo’s group in the School of Arts & Sciences at Penn and Drew Weissman of the Perelman School of Medicine to figure out the molecular mechanisms that make tumor microenvironments seemingly impenetrable and found that small extracellular vesicles (sEVs) are secreted by tumor cells and act as a “forcefield,” blocking therapeutics. Their findings are published in Nature Materials.
“This discovery reveals how tumors create a robust defense system, making it challenging for nanoparticle-based therapies to reach and effectively target cancer cells,” Guo says. “By understanding the cellular mechanisms driving these responses, we can potentially develop strategies to disable this defense, allowing therapeutics to penetrate and attack the tumor more efficiently.”
The research builds on a prior collaboration between Guo and Mitchell’s labs, wherein the teams focused on how tumor-associated immune cells, known as macrophages, contribute to the suppression of anti-tumor immunity by secreting extracellular vesicles.
Wei Guo is the Hirsch Family President’s Distinguished Professor in the Department of Biology in Penn’s School of Arts & Sciences.
Ningqiang Gong, a former postdoctoral researcher in the Mitchell lab at Penn Engineering, is an assistant professor at the University of Science and Technology of China.
Wenqun Zhong is a reseearch associate in the Guo Laboratory in Penn Arts & Sciences.
Other authors include: Alex G Hamilton, Dongyoon Kim, Junchao Xu, and Lulu Xue of Penn Engineering; Junhyong Kim, Zhiyuan Qin, and Fengyuan Xu of Penn Arts & Sciences; Mohamad-Gabriel Alameh and Drew Weissman of the Perelman School of Medicine; Andrew E. Vaughn and Gan Zhao of the Penn School of Veterinary Medicine; Jinghong Li and Xucong Teng of the University of Beijing; and Xing-Jie Liang of the Chinese Academy of Sciences.
This research received support from the U.S. National Institutes of Health (DP2 TR002776, R35 GM141832, and NCI P50 CA261608), Burroughs Wellcome Fund, U.S. National Science Foundation CAREER Award (CBET-2145491), and an American Cancer Society Research Scholar Grant (RGS-22-1122-01-ET.)
“Senior Design was such an incredible part of my senior year and Penn Engineering experience that when I joined the Board of the Engineering Alumni Society, I knew immediately that I would focus on helping the event continue,” says Lyle Brunhofer (EAS’14, GEng’14).
Today, Lyle Brunhofer (EAS’14, GEng’14) advises companies on digital transformations, applying the skills he learned at Penn Engineering to modernize firms’ understanding of customers in industries as diverse as pharmaceuticals and consumer products.
He also helps run Penn Engineering’s annual Senior Design Project Competition, which recruits dozens of alumni to evaluate seniors’ year-long capstone projects. As the Vice President and Senior Design Chair of the Engineering Alumni Society, Brunhofer works hand-in-hand with Bradley Richards (C’92, LPS’17), Director of Alumni Relations, to coordinate the year-long competition and multi-day concluding extravaganza — part Shark Tank, part science competition — in May.
While at Penn Engineering, Brunhofer’s own Senior Design team developed assistive technology to help those with physical disabilities interact with their environment using modular, 3D printed switches. Assist3D partnered with the HMS School for Children with Cerebral Palsy, located in West Philadelphia, to ensure that products met users’ needs. “We set out to create ability switches that would be affordable, customizable and simple, in contrast to the ability switches available on the market,” Brunhofer recalls. After graduation, the team provided the finished products to the HMS School.
As Brunhofer sees it, Senior Design instills skills far beyond the scope of typical engineering courses. “As a student, I felt that Senior Design was an extremely challenging, but rewarding experience,” he says. “It was also unlike any assignment we had been given previously.”
In a Q&A with Penn Engineering Today, Brunhofer discussed what motivates him to stay involved with Penn Engineering as an alumnus and the impact of participating in Senior Design.
How did you get involved as an alumni volunteer with Senior Design?
Senior Design was such an incredible part of my senior year and Penn Engineering experience that when I joined the Board of the Engineering Alumni Society, I knew immediately that I would focus on helping the event continue.
What do you feel makes Senior Design unique?
The mentorship. Students get to work with industry experts, faculty members, alumni and other professionals who help students hone their technical and soft skills, and foster networking opportunities for future careers.
Lyle Brunhofer is Business Integration Manager at Accenture. He graduated with Bachelor’s and Master’s degrees in Bioengineering from the University of Pennsylvania in 2014.
Biomaterials 3D-printed with the new method can be used inside the body and could even serve as bandages on a beating human heart. (Photo by Casey A. Cass/University of Colorado)
In the quest to develop life-like materials to replace and repair human body parts, scientists face a formidable challenge: Real tissues are often both strong and stretchable and vary in shape and size.
A CU Boulder-led team, in collaboration with researchers at the University of Pennsylvania, has taken a critical step toward cracking that code. They’ve developed a new way to 3D print material that is at once elastic enough to withstand a heart’s persistent beating, tough enough to endure the crushing load placed on joints, and easily shapeable to fit a patient’s unique defects.
Their breakthrough, described in the Aug. 2 edition of the journal Science, helps pave the way toward a new generation of biomaterials, from internal bandages that deliver drugs directly to the heart to cartilage patches and needle-free sutures.
“This is a simple 3D processing method that people could ultimately use in their own academic labs as well as in industry to improve the mechanical properties of materials for a wide variety of applications,” says first author Abhishek Dhand, a researcher in the Burdick Lab and doctoral candidate in the Department of Bioengineering at the University of Pennsylvania. “It solves a big problem for 3D printing.”
Jason Burdick is Bowman Endowed Professor in Chemical and Biological Engineering at the University of Colorado Boulder and Adjunct Professor in Bioengineering at Penn Engineering.
BE’s award-winning team, Epilog, at the 2024 Senior Design Awards.
How do you make robotics kits affordable for children in low-income countries? Speed up the manufacturing of organs-on-a-chip? Lower the environmental impact of condiments in restaurants?
If you’re a senior at Penn Engineering, the answer is to team up with your peers in the Senior Design Project Competition, which every year draws interdisciplinary groups from across the School’s six majors to solve real-world problems. Championed by the late Walter Korn (EE’57, GEE’68), a past president of the Engineering Alumni Society (EAS), Senior Design also invites alumni back to campus to evaluate the seniors’ year-long capstone projects.
Since the program started nearly two decades ago, hundreds of alumni have shared centuries’ worth of their collective experience with soon-to-be-minted graduates in the form of constructive feedback. “Senior Design is really one of the best days at Penn Engineering,” says Bradley Richards (C’92, LPS’17), Director of Alumni Relations, who manages the program. “Faculty advisors work with students all year long to bring out the best in each group’s efforts, and the results speak for themselves.”
This year, three student teams from each of Penn Engineering’s six departments — Bioengineering (BE), Chemical and Biomolecular Engineering (CBE), Computer and Information Science (CIS), Electrical and Systems Engineering (ESE), Materials Science and Engineering (MSE), and Mechanical Engineering and Applied Mechanics (MEAM) — presented their work to more than 60 alumni in person and online.
Judges’ Choice Award
The Judges’ Choice Award, which recognizes overall excellence, went to ESE’s VivoDisk, which developed a novel machine to manufacture organs-on-a-chip for Vivodyne, a startup launched by Dan Huh, Associate Professor in BE.
As one of the team members, Akash Chauhan (ENG’24), learned while interning for Vivodyne, assembling the stacks of organs-on-a-chip, which are collections of plastic plates containing cells that simulate organs for preclinical drug testing, is extremely finicky and time consuming.
By developing a machine that could automatically align the plates with high precision using computer vision and AI, the team reduced the disks’ manufacturing time and expense, leading Vivodyne to adopt the device for commercial use, accelerating the process of drug discovery. VivoDisk’s team members included Chauhan; Angela Rodriguez (ENG’24), Aliris Tang (ENG’24, W’24), Dagny Lott (ENG’24), Simone Kwee (ENG’24) and Vraj Satashia (ENG’24, GEN’25) and was advised by Sid Deliwala, Alfred Moore Senior Fellow and Director of Lab Programs in ESE, and Jan Van der Spiegel, Professor in ESE.
Technology and Innovation Award
One of the greatest challenges for children with epilepsy is status epilepticus, an abnormal type of long-lasting seizure that is hard to distinguish from typical seizures and that has a mortality rate of 30%. There is currently no way to perform a test for status epilepticus at home, meaning that children suspected of having the condition must be rushed to the hospital for an electroencephalogram.
Epilog, a team from BE, developed a novel, wearable headset that analyzes brainwaves to accurately determine whether or not a child suffering a seizure is actually suffering from status epilepticus. The team, composed of Rohan Chhaya (ENG’24, GEN’24), Carly Flynn (ENG’24), Elena Grajales (ENG’24), Priya Shah (ENG’24, GEN’25) and Doris Xu (ENG’24) and advised by Erin Berlew, Research Scientist in the Department of Orthopaedic Surgery and Lecturer in BE, carefully validated the device’s accuracy.
The judges recognized Epilog’s technological expertise, which ran the gamut from software to hardware, including a custom app to work with the device and carefully considered features like electrodes whose position can be adjusted to accommodate a child’s growth over time.
Bicontinuous materials, like this representation of a cube of gelatin and hyaluronic acid, have greater internal surface area, allowing cells to travel faster between two points. (Credit: Karen Xu)
One of the most important but least understood aspects of healing is cell migration, or the process of cells moving from one part of the body to another. “If you are an ambulance out in the woods,” says Karen Xu, an M.D/Ph.D. student in Medicine and Bioengineering, “and there are no paths for you to move forward, it will be a lot harder for you to get to a site that needs you.”
Earlier this year, Xu co-authored a paper in Nature Communications describing a new cue to help cells get to where they need to go: a material made chiefly of hyaluronic acid and gelatin, two gooey substances commonly found outside cells in joints and connective tissue.
“Hundreds of thousands of people tear their meniscus every year,” says Robert Mauck, Mary Black Ralston Professor in Orthopaedic Surgery in Penn Medicine and Professor in Bioengineering at Penn Engineering and one of Xu’s advisors, as well as a senior author on the paper. “This material could potentially speed up their recovery.”
What makes the material — known as a hydrogel due to its blend of gelatinous matter and water — unique is that the combination of hyaluronic acid and gelatin forms a complex network of paths, providing cells many different ways to travel between two points.
This property is known as bicontinuity, and is exemplified by two discrete continuous phases that are each connected throughout the entire volume of the material (for example with a sponge, with phases of cellulose and air; in the hydrogel, this is comprised of gelatin and hyaluronic acid) resulting in a dizzying array of patterns that dramatically increase the surface area inside the material.
To test the hydrogel’s efficacy, Xu and her collaborators — including co-advisor Jason Burdick, formerly the Robert D. Bent Professor in Bioengineering at Penn Engineering and now the Bowman Endowed Professor at the University of Colorado Boulder, and the paper’s other senior author — first created several different versions of the hydrogel to find the sweet spot at which the constituents formed the bicontinuous structure and had the highest internal surface area. “We found that a precise combination of the various hydrogel components and control over their mixing was needed to form the bicontinuous structure,” says Burdick.
