鈥淥ur digital technology operates through a series of electronic on-off switches that control the flow of current and voltage,鈥� said , a research scientist at the 天美影视传媒. 鈥淏ut our bodies operate on chemistry. In our brains, neurons propagate signals electrochemically, by moving ions 鈥� charged atoms or molecules 鈥� not electrons.鈥�

Implantable devices from pacemakers to glucose monitors rely on components that can speak both languages and bridge that gap. Among those components are OECTs 鈥� or organic electrochemical transistors 鈥� which allow current to flow in devices like implantable biosensors. But scientists long knew about a quirk of OECTs that no one could explain: When an OECT is switched on, there is a lag before current reaches the desired operational level. When switched off, there is no lag. Current drops almost immediately.

A UW-led study has solved this lagging mystery, and in the process paved the way to custom-tailored OECTs for a growing list of applications in biosensing, brain-inspired computation and beyond.

鈥淗ow fast you can switch a transistor is important for almost any application,鈥� said project leader , a UW professor of chemistry, chief scientist at the UW Clean Energy Institute and faculty member in the UW Molecular Engineering and Sciences Institute. 鈥淪cientists have recognized the unusual switching behavior of OECTs, but we never knew its cause 鈥� until now.鈥�

In a published April 17 in Nature Materials, Ginger鈥檚 team at the UW 鈥� along with Professor at the Okinawa Institute of Science and Technology in Japan and Professor at Zhejiang University in China 鈥� report that OECTs turn on via a two-step process, which causes the lag. But they appear to turn off through a simpler one-step process.

In principle, OECTs operate like transistors in electronics: When switched on, they allow the flow of electrical current. When switched off, they block it. But OECTs operate by coupling the flow of ions with the flow of electrons, which makes them interesting routes for interfacing with chemistry and biology.

The new study illuminates the two steps OECTs go through when switched on. First, a wavefront of ions races across the transistor. Then, more charge-bearing particles invade the transistor鈥檚 flexible structure, causing it to swell slightly and bringing current up to operational levels. In contrast, the team discovered that deactivation is a one-step process: Levels of charged chemicals simply drop uniformly across the transistor, quickly interrupting the flow of current.

Knowing the lag鈥檚 cause should help scientists design new generations of OECTs for a wider set of applications.

鈥淭here鈥檚 always been this drive in technology development to make components faster, more reliable and more efficient,鈥� Ginger said. 鈥淵et, the 鈥榬ules鈥� for how OECTs behave haven鈥檛 been well understood. A driving force in this work is to learn them and apply them to future research and development efforts.鈥�

Whether they reside within devices to measure blood glucose or brain activity, OECTs are largely made up of flexible, organic semiconducting polymers 鈥� repeating units of complex, carbon-rich compounds 鈥� and operate immersed in liquids containing salts and other chemicals. For this project, the team studied OECTs that change color in response to electrical charge. The polymer materials were synthesized by Luscombe鈥檚 team at the Okinawa Institute of Science and Technology and Li鈥檚 at Zhejiang University, and then fabricated into transistors by UW doctoral students Jiajie Guo and Shinya 鈥淓merson鈥� Chen, who are co-lead authors on the paper.

鈥淎 challenge in the materials design for OECTs lies in creating a substance that facilitates effective ion transport and retains electronic conductivity,鈥� said Luscombe, who is also a UW affiliate professor of chemistry and of materials science and engineering. 鈥淭he ion transport requires a flexible material, whereas ensuring high electronic conductivity typically necessitates a more rigid structure, posing a dilemma in the development of such materials.鈥�

Guo and Chen observed under a microscope 鈥� and recorded with a smartphone camera 鈥� precisely what happens when the custom-built OECTs are switched on and off. It showed clearly that a two-step chemical process lies at the heart of the OECT activation lag.

Past research, including by Ginger鈥檚 group at the UW, demonstrated that polymer structure, especially its flexibility, is important to how OECTs function. These devices operate in fluid-filled environments containing chemical salts and other biological compounds, which are more bulky compared to the electronic underpinnings of our digital devices.

The new study goes further by more directly linking OECT structure and performance. The team found that the degree of activation lag should vary based on what material the OECT is made of, such as whether its polymers are more ordered or more randomly arranged, according to Giridharagopal. Future research could explore how to reduce or lengthen the lag times, which for OECTs in the current study were fractions of a second.

鈥淒epending on the type of device you鈥檙e trying to build, you could tailor composition, fluid, salts, charge carriers and other parameters to suit your needs,鈥� said Giridharagopal.

OECTs aren鈥檛 just used in biosensing. They are also used to study nerve impulses in muscles, as well as forms of computing to create artificial neural networks and understand how our brains store and retrieve information. These widely divergent applications necessitate building new generations of OECTs with specialized features, including ramp-up and ramp-down times, according to Ginger.

鈥淣ow that we鈥檙e learning the steps needed to realize those applications, development can really accelerate,鈥� said Ginger.

Guo is now a postdoctoral researcher at the Lawrence Berkeley National Laboratory and Chen is now a scientist at Analog Devices. Other co-authors on the paper are , a former UW postdoctoral researcher in chemistry who is now an assistant professor at the University of Utah; Jonathan Onorato, a UW doctoral alum and scientist at Exponent; and Kangrong Yan and Ziqui Shen of Zhejiang University. The research was funded by the U.S. National Science Foundation, and polymers developed at Zhejiang University were funded by the National Science Foundation of China.

For more information contact Ginger at dginger@uw.edu, Luscombe at christine.luscombe@oist.jp and Giridharagopal at rgiri@uw.edu.

These cells make another protein, called islet amyloid polypeptide or IAPP, which has been found clumped together in many Type 2 diabetes patients. The formation of IAPP clusters is comparable to how a to eventually form the signature plaques associated with that disease.

Researchers at the 天美影视传媒 have demonstrated more similarities between IAPP clusters and those in Alzheimer’s. The team previously showed that a synthetic peptide can block the formation of small, toxic Alzheimer’s protein clusters. Now, in a in Protein Science, the researchers used a similar peptide to block the formation of IAPP clusters.

UW News asked co-senior author , a UW professor of bioengineering and faculty member in the UW , for details about protein aggregation and how these synthetic peptides work.

Alzheimer’s and Type 2 diabetes are part of a family of diseases that are characterized by having proteins that cluster together. What’s happening?

Valerie Daggett: There are over 50 of these amyloid diseases, and they start out with their respective proteins in their biologically active, good form. But then the proteins start changing structure and globbing together. These aggregates can be different sizes. They can have different underlying structures and different effects on the cells around them.

Early in the process there are smaller clusters, which are toxic, and they set off all kinds of problems. This leads to a very complicated disease because lots of other things go awry in response to these toxic clusters. Over time, these clusters combine to form non-toxic structures: longer strands and finally large deposits, such as the Alzheimer’s plaques.

Many people know that protein aggregation plays a role in neurodegenerative diseases, such as Alzheimer’s disease. Can you describe what’s happening here?

Valerie Daggett will deliver this year’s University Faculty Lecture at 5:30 p.m. on Monday, April 1.

VD: In the case of Alzheimer’s, these small, toxic protein clusters are running around the brain attacking neurons and then over time there’s enough damage that we start to see symptoms. By the time these clusters have combined to form the non-toxic plaques, there’s already been a lot of damage. It becomes similar to trying to treat stage 4 cancer. That’s why we want to get in early.

What’s happening with Type 2 diabetes?

VD: It’s similar, except it鈥檚 happening in the pancreas instead of the brain. In healthy people, cells in the pancreas, called beta cells, secrete IAPP along with insulin. The normal, active form of IAPP helps with metabolism maintenance. But when IAPP changes shape, it starts to form these toxic clusters and then it starts attacking the beta cells. And these clusters are equal-opportunity toxins. We, and many others, have shown that you can put them on different cell types and they will kill the cells.

In this paper, you show that the IAPP clusters go through an “” phase. What does this mean and why is it significant?

VD: We’ve been looking at these amyloid systems for a long time and we started seeing this weird protein structure. It’s like every other one of the protein building blocks, called amino acids, has had this crankshaft motion on it. Half of them are rotated the wrong way.

At first we thought: “That’s got to be an artifact. Nobody discovers a new structure.” But we’ve since shown that this “alpha sheet” structure is real. And proteins in all the amyloid systems we’ve looked at 鈥� 14 now including Type 2 diabetes 鈥� form these alpha sheet structures when they’re in these small, toxic clusters. No one had seen that for IAPP before this paper.

Also in this paper, you showed that a synthetic peptide was able to bind and neutralize the toxic IAPP clusters and keep beta cells alive. What’s special about this peptide and how does it work?

VD: Previously, we designed synthetic peptides to bind to the toxic protein clusters in Alzheimer’s disease. The idea here is for these peptides to take these clusters out of commission before they can wreak havoc on the cells. The peptide we made also forms an alpha sheet structure, but it is not toxic to the cells. It binds really tightly to the clusters, and we’re currently studying what happens to the clusters after it binds.

In this paper, we showed that our synthetic peptides also work against the toxic IAPP clusters, which means this could be a potential therapeutic in the future.

Type 2 diabetes is the most prevalent amyloid disease 鈥� it affects . A lot of people associate Type 2 diabetes treatment with changing lifestyle measures, but that doesn’t work for everyone. A drug that could help minimize the damage IAPP does to the pancreas could be really helpful.

This paper had two lead authors: , who completed this research as a UW doctoral student of molecular engineering and is now at Columbia University, and , who completed this research as an acting instructor of medicine in the UW School of Medicine and is now at Indiana University. Additional co-authors on this paper are Tatum Prosswimmer, a UW doctoral student of molecular engineering; , who completed this research as a UW doctoral student of molecular engineering and is now at Ambit Inc; , who completed this research as a UW undergraduate student majoring in biochemistry and is now a student at Pacific Northwest University of Health Sciences; , who completed this research as a senior research scientist in the Division of Metabolism, Endocrinology and Nutrition in the UW School of Medicine and is now at Tacoma Community College; and , professor of medicine in the UW School of Medicine.

This research was funded by the National Institutes of Health, the 天美影视传媒 Office of Research, the UW Department of Bioengineering, the Department of Veterans Affairs, the American Diabetes Association and a UW Mary Gates Research Scholarship.

For more information, contact Daggett at daggett@uw.edu.

Quantum computing could revolutionize our world. For specific and crucial tasks, it promises to be exponentially faster than the zero-or-one binary technology that underlies today鈥檚 machines, from supercomputers in laboratories to smartphones in our pockets. But developing quantum computers hinges on building a stable network of qubits 鈥� or quantum bits 鈥� to store information, access it and perform computations.

Yet the qubit platforms unveiled to date have a common problem: They tend to be delicate and vulnerable to outside disturbances. Even a stray photon can cause trouble. Developing fault-tolerant qubits 鈥� which would be immune to external perturbations 鈥� could be the ultimate solution to this challenge.

A team led by scientists and engineers at the 天美影视传媒 has announced a significant advancement in this quest. In a pair of papers published and , they report that, in experiments with flakes of semiconductor materials 鈥� each only a single layer of atoms thick 鈥� they detected signatures of 鈥渇ractional quantum anomalous Hall鈥� (FQAH) states. The team鈥檚 discoveries mark a first and promising step in constructing a type of fault-tolerant qubit because FQAH states can host anyons 鈥� strange 鈥渜uasiparticles鈥� that have only a fraction of an electron鈥檚 charge. Some types of anyons can be used to make what are called 鈥渢opologically protected鈥� qubits, which are stable against any small, local disturbances.

鈥淭his really establishes a new paradigm for studying quantum physics with fractional excitations in the future,鈥� said , the lead researcher behind these discoveries, who is also the Boeing Distinguished Professor of Physics and a professor of materials science and engineering at the UW.

FQAH states are related to the , an exotic phase of matter that exists in two-dimensional systems. In these states, electrical conductivity is constrained to precise fractions of a constant known as the conductance quantum. But fractional quantum Hall systems typically require massive magnetic fields to keep them stable, making them impractical for applications in quantum computing. The FQAH state has no such requirement 鈥� it is stable even 鈥渁t zero magnetic field,鈥� according to the team.

Hosting such an exotic phase of matter required the researchers to build an artificial lattice with exotic properties. They stacked two atomically thin flakes of the semiconductor material molybdenum ditelluride (MoTe₂) at small, mutual 鈥渢wist鈥� angles relative to one another. This configuration formed a synthetic 鈥渉oneycomb lattice鈥� for electrons. When researchers cooled the stacked slices to a few degrees above absolute zero, an intrinsic magnetism arose in the system. The intrinsic magnetism takes the place of the strong magnetic field typically required for the fractional quantum Hall state. Using lasers as probes, the researchers detected signatures of the FQAH effect, a major step forward in unlocking the power of anyons for quantum computing.

The team 鈥� which also includes scientists at the University of Hong Kong, the National Institute for Materials Science in Japan, Boston College and the Massachusetts Institute of Technology 鈥� envisions their system as a powerful platform to develop a deeper understanding of anyons, which have very different properties from everyday particles like electrons. Anyons are quasiparticles 鈥� or particle-like 鈥渆xcitations鈥� 鈥� that can act as fractions of an electron. In future work with their experimental system, the researchers hope to discover an even more exotic version of this type of quasiparticle: 鈥渘on-Abelian鈥� anyons, which could be used as topological qubits. Wrapping 鈥� or 鈥渂raiding鈥� 鈥� the non-Abelian anyons around each other In this quantum state, information is essentially 鈥渟pread out鈥� over the entire system and resistant to local disturbances 鈥� forming the basis of topological qubits and a major advancement over the capabilities of current quantum computers.

鈥淭his type of topological qubit would be fundamentally different from those that can be created now,鈥� said UW physics doctoral student Eric Anderson, who is lead author of the Science paper and co-lead author of the Nature paper. 鈥淭he strange behavior of non-Abelian anyons would make them much more robust as a quantum computing platform.鈥�

Three key properties, all of which existed simultaneously in the researchers鈥� experimental setup, allowed FQAH states to emerge:

• Magnetism: Though MoTe₂ is not a magnetic material, when they loaded the system with positive charges, a 鈥渟pontaneous spin order鈥� 鈥� a form of magnetism called ferromagnetism 鈥� emerged.
• Topology: Electrical charges within their system have 鈥渢wisted bands,鈥� similar to a M枚bius strip, which helps make the system topological.
• Interactions: The charges within their experimental system interact strongly enough to stabilize the FQAH state.

The team hopes that, using their approach, non-Abelian anyons await for discovery.

鈥淭he observed signatures of the fractional quantum anomalous Hall effect are inspiring,鈥� said UW physics doctoral student , co-lead author on the Nature paper and co-author of the Science paper. 鈥淭he fruitful quantum states in the system can be a laboratory-on-a-chip for discovering new physics in two dimensions, and also new devices for quantum applications.鈥�

鈥淥ur work provides clear evidence of the long-sought FQAH states,鈥� said Xu, who is also a member of the Molecular Engineering and Sciences Institute, the Institute for Nano-Engineered Systems and the Clean Energy Institute, all at UW. 鈥淲e are currently working on electrical transport measurements, which could provide direct and unambiguous evidence of fractional excitations at zero magnetic field.鈥�

The team believes that, with their approach, investigating and manipulating these unusual FQAH states can become commonplace 鈥� accelerating the quantum computing journey.

Additional co-authors on the papers are William Holtzmann and Yinong Zhang in the UW Department of Physics; Di Xiao, Chong Wang, Xiaowei Zhang, Xiaoyu Liu and Ting Cao in the UW Department of Materials Science & Engineering; Feng-Ren Fan and Wang Yao at the University of Hong Kong and the Joint Institute of Theoretical and Computational Physics at Hong Kong; Takashi Taniguchi and Kenji Watanabe from the National Institute of Materials Science in Japan; Ying Ran of Boston College; and Liang Fu at MIT. The research was funded by the U.S. Department of Energy, the Air Force Office of Scientific Research, the National Science Foundation, the Research Grants Council of Hong Kong, the Croucher Foundation, the Tencent Foundation, the Japan Society for the Promotion of Science and the 天美影视传媒.

For more information, contact Xu at xuxd@uw.edu, Anderson at eca55@uw.edu and Cai at caidish@uw.edu.

In a world abuzz with smartphones, tablets, 5G and Siri, there are whispers of something new over the horizon 鈥� and it isn鈥檛 artificial intelligence!

A growing field of research seeks to develop technologies built directly on the seemingly strange and contradictory rules of quantum mechanics. These principles underlie the behavior of atoms and everything comprised of atoms, including people. But these rules are only apparent at very small scales. Researchers across the globe are constructing rudimentary quantum computers, which could perform computational tasks that the 鈥渃lassical鈥� computers in our pockets and on our desks simply could not.

To help transform these quantum whispers into a chorus, scientists at the 天美影视传媒 are pursuing multiple quantum research projects spanning from creating materials with never-before-seen physical properties to studying the 鈥渜uantum bits鈥� 鈥� or qubits (pronounced “kyu-bits”) 鈥� that make quantum computing possible.

With their in the Department of Physics and the Department of Electrical & Computer Engineering, UW Professor studies the quantum-level properties of crystalline materials for potential applications in electrical and optical quantum technologies. In addition, Fu, who is also a faculty member in the Molecular & Engineering Sciences Institute and the Institute for Nano-engineered Systems, has led efforts to develop a comprehensive graduate curriculum and provide internship opportunities in quantum sciences for students in fields ranging from computer science to chemistry 鈥� all toward the goal of forging a quantum-competent workforce.

UW News sat down with Fu to talk about the potential of quantum research, and why it鈥檚 so important.

Let鈥檚 start with the obvious. What is “quantum?”

Kai-Mei Fu: Originally, “quantum” just meant “discrete.” It referred to the observation that, at really small scales, something can exist only in discrete states. This is different from our everyday experiences. For example, if you start a car and then accelerate, the car 鈥渁ccesses鈥� every speed. It can occupy any position. But when you get down to these really small systems 鈥� unusually small 鈥� you start to see that every “position” may not be accessible. And similarly, every speed or energy state may not be accessible. Things are “quantized” at this level.

And that’s not the only weird thing that’s going on: At this small scale, not only do things exist in discrete states, but it is possible for things to exist in a combination of two or more different states at once. This is called “superposition,” and that is when the interesting physical phenomena occur.

How is superposition useful in developing quantum technology?

KMF: Well, let’s take quantum computing for example. In the information age of today, a computational “bit” can only exist in one of two possible states: 0 and 1. But with superposition, you could have a qubit that can exist in two different states at the same time. It’s not just that you don’t know which state it’s in. It really is coexisting in two different states. Thus it is possible to compute with many states, in fact exponentially many states, at the same time. With quantum computing and quantum information, the power is in being able to control that superposition.

What are some exciting advancements or applications that could stem from controlling superposition?

KMF: There are four main areas of excitement. My favorite is probably quantum computation. It’s the one that’s furthest out technologically 鈥� right now, computation involving just a handful of qubits has been realized 鈥� but it’s kind of the big one.

We know that the power of quantum computation will be immense because 聽superposition is scalable. This means that you would have so much more computational space to utilize, and you could perform computations that our classical computers would need the age of the universe to perform. So, we know that there’s a lot of power in quantum computing. But there’s also a lot of speculation in this field, and questions about how you can harness that power.

Does the 天美影视传媒 have a quantum computer?

KMF: It currently does not. We are gathering materials now to construct a quantum processor 鈥� the basis of a quantum computer 鈥� as part of our educational curriculum in this field.

Besides quantum computing, what other applications are there?

KMF: Another area is sensing for more precise measurements. One example: single-atom crystals that can act as sensors. For my research, I work with atoms arranged into a perfect crystal and then I create “defects” by adding in different types of atoms or taking out one atom in the lattice. The defect acts like an artificial atom and it will react to tiny changes nearby, such as a change in a magnetic field. These changes are normally so small that they would be hard to measure at room temperature, but the artificial atom amplifies the changes into something I can see 鈥� sometimes even by eye. For example, some crystals will radiate light when I shine a laser on them. By measuring the light they emit, I can detect a change.

This is so special. I get super excited because we know that all these things are possible in theory, but we’ve just hit the timescale where we’re starting to see real technological applications right now.

That sounds really exciting!

KMF: Another area I’ll mention is quantum simulation. There are a lot of potential applications in this field, such as studying new energy storage systems or figuring out how to make an enzyme better at nitrogen fixation. Essentially these problems require making new materials, but these are complex quantum systems that are hard for classical computers to simulate or predict. But quantum simulation could, and this could be done using a type of quantum computer. The field is expecting a lot of advancement in materials and other areas from quantum simulation.

The final area is quantum communication. When you’re transmitting sensitive information, you can create a key to encrypt it. With quantum encryption you can distribute a key that’s so fundamentally secure that if you have an eavesdropper, they leave a “mark” behind that you can detect.

How big is the field of quantum communication? Is it happening now?

KMF: Well, in the past few years, quantum communication became a prominent topic in government when China .

Let’s shift gears a little to talk about quantum in terms of workforce development. You have companies, national labs and universities all pursuing quantum research. Are there any specific challenges for quantum education?

KMF: What we are doing is crafting a common framework 鈥� a common language 鈥� for education in quantum. Quantum involves many fields, including chemistry, computer science, material science, chemical engineering and theoretical physics. Historically these fields have all had their own approach, their own vocabulary, their own history. At the 天美影视传媒, we’ve launched a core curriculum in quantum for graduate students who want to pursue careers in this field. Through the , we also have partners for internships.

We need more scientists in quantum because this is an exciting time. A lot is changing. There are many questions to answer, too many. Every field in quantum is growing in its own way. In the coming years, this is going to change a lot about how we approach problems 鈥� in communication, in software, in medicine and in materials. It will be beyond what we can think about even today.

For more information, contact Fu at kaimeifu@uw.edu.

Seven professors at the 天美影视传媒 are among 25 new members of the Washington State Academy of Sciences, according to a . Joining the academy is a recognition of 鈥渢heir outstanding record of scientific and technical achievement, and their willingness to work on behalf of the Academy to bring the best available science to bear on issues within the State of Washington.鈥�

Twenty of the incoming members for 2022 were selected by current WSAS members, while the other five were chosen by virtue of recently joining one of the National Academies.

UW faculty selected by current Academy members are:

• , the Robert G. and Jean A. Reid Executive Dean of Nursing, 鈥渇or pioneering research in cultural competence, conducting international collaborative research with professionals and family caregivers of older adults with dementia, advancing assessment of cultural awareness and its impact on healthcare, and supporting establishment of UW鈥檚 Center for Global Health Nursing and the first Center for Anti-Racism in Nursing.鈥�
• , the Harry and Catherine Jaynne Boand Endowed Professor of Chemistry, co-associate chair of the Department of Chemistry, and associate vice provost for research cyberinfrastructure, 鈥渇or a body of work that supercharges computational chemistry, including pioneering work in time- dependent electronic structure theory and quantum mechanical techniques,鈥� and 鈥渇or exemplary collaborative efforts, as well as leadership in developing educational pathways for underrepresented minority students in STEM.鈥� Li is also a faculty member in the UW Clean Energy Institute and the UW Molecular & Engineering Sciences Institute.
• , the Steven and Connie Rogel Endowed Professor of Chemical Engineering, professor of chemistry, and chair of the Department of Chemical Engineering, 鈥渇or pioneering contributions that advanced the frontiers of molecular simulation, impacting the prediction of enzyme activity in ionic liquids, peptide interactions with surfaces and molecular design.鈥� Pfaendtner is also a faculty member in the Clean Energy Institute and the Molecular & Engineering Sciences Institute, as well as a senior data fellow with the UW eScience Institute and staff scientist at the Pacific Northwest National Laboratory.
• , the Klaus and Mary Ann Saegebarth Endowed Professor of Chemistry, 鈥渇or pioneering fundamental and applied studies in mass spectrometry, physical chemistry, and newborn screening鈥� as well as 鈥減ropagation of science, science education, and technical expertise contributions to startup companies in Washington state.鈥�
• , the Kyocera Professor in Materials Science & Engineering and vice dean of the College of Engineering, 鈥渇or pioneering contribution to the discovery of new thermoelectric and energy storage materials for clean energy, and for exceptional leadership to promote interdisciplinary collaboration among academia, industry, and national laboratories for creating transformational and sustainable impact for Washington.鈥� Yang is also a faculty member in the Clean Energy Institute and the Molecular & Engineering Sciences Institute.
• Dr. , professor of radiology and director of the UW Medicine Image-Guided Bio-Molecular Intervention Laboratory, 鈥渇or work as an internationally prominent physician-scientist in the field of image-guided minimally invasive interventional therapies鈥� and 鈥渇or pioneering contributions and outstanding achievements in developing innovative and cutting-edge medical imaging and interventional radiology for effective management of life-threatening diseases, such as atherosclerotic cardiovascular disease and cancer.鈥�

In addition, Dr. , UW professor of genome sciences, investigator with the Howard Hughes Medical Institute and faculty member in the Molecular Engineering & Sciences Institute, was selected by virtue of his election to the National Academy of Sciences 鈥渇or pioneering a variety of genome sequencing and analysis methods, including exome sequencing and its earliest applications to gene discovery for Mendelian disorders and autism; cell-free DNA diagnostics for cancer and reproductive medicine; massively parallel reporter assays; saturation genome editing; whole organism lineage tracing; and massively parallel molecular profiling of single cells.鈥�

New members to the Washington State Academy of Sciences will be formally inducted in September.

Researchers have discovered that light 鈥斅爄n the form of a laser 鈥斅燾an trigger a form of magnetism in a normally nonmagnetic material. This magnetism centers on the behavior of electrons. These subatomic particles have an electronic property called 鈥渟pin,鈥� which has a potential application in quantum computing. The researchers found that electrons within the material became oriented in the same direction when illuminated by photons from a laser.

The experiment, led by scientists at the 天美影视传媒, the University of Hong Kong and the Pacific Northwest National Laboratory, was April 20 in Nature.

By controlling and aligning electron spins at this level of detail and accuracy, this platform could have applications in the field of quantum simulation, according to co-senior author , a Boeing Distinguished Professor at the UW in the Department of Physics and the Department of Materials Science and Engineering, and scientist at the Pacific Northwest National Laboratory.

鈥淚n this system, we can use photons essentially to control the 鈥榞round state鈥� properties 鈥斅爏uch as magnetism 鈥斅爋f charges trapped within the semiconductor material,鈥� said Xu, who is also a faculty researcher with the UW鈥檚聽, the , and the . 鈥淭his is a necessary level of control for developing certain types of 鈥斅爋r 鈥榪uantum bits鈥� 鈥斅爁or and other applications.鈥�

Xu, whose research team spearheaded the experiments, led the study with co-senior author Wang Yao, professor of physics at the University of Hong Kong, whose team worked on the theory underpinning the results. Other UW faculty members involved in this study are co-authors , a UW professor of physics and of materials science and engineering who also holds a joint appointment at the Pacific Northwest National Laboratory, and , a UW professor of chemistry, director of the , and faculty member in the Clean Energy Institute and the Molecular Engineering & Sciences Institute.

The team worked with ultrathin sheets 鈥斅爀ach just three layers of atoms thick 鈥斅爋f tungsten diselenide and tungsten disulfide. Both are semiconductor materials, so named because electrons move through them at a rate between that of a fully conducting metal and an insulator, with potential uses in photonics and solar cells. Researchers stacked the two sheets to form a 鈥渕oir茅 superlattice,鈥� a stacked structure made up of repeating units.

Stacked sheets like these are powerful platforms for quantum physics and materials research because the superlattice structure can hold excitons in place. Excitons are bound pairs of 鈥渆xcited鈥� electrons and their associated positive charges, and scientists can measure how their properties and behavior change in different superlattice configurations.

The researchers were studying the exciton properties within the material when they made the surprising discovery that light triggers a key magnetic property within the normally nonmagnetic material. Photons provided by the laser 鈥渆xcited鈥� excitons within the laser beam鈥檚 path, and these excitons induced a type of long-range correlation among other electrons, with their spins all orienting in the same direction.

鈥淚t鈥檚 as if the excitons within the superlattice had started to 鈥榯alk鈥� to spatially separated electrons,鈥� said Xu. 鈥淭hen, via excitons, the electrons established exchange interactions, forming what鈥檚 known as an 鈥榦rdered state鈥� with aligned spins.鈥�

The spin alignment that the researchers witnessed within the superlattice is a characteristic of ferromagnetism, the form of magnetism intrinsic to materials like iron. It is normally absent from tungsten diselenide and tungsten disulfide. Each repeating unit within the moir茅 superlattice is essentially acting like a to 鈥渢rap鈥� an electron spin, said Xu. Trapped electron spins that can 鈥渢alk鈥� to each other, as these can, have been suggested as the basis for a type of qubit, the basic unit for quantum computers that could harness the unique properties of quantum mechanics for computation.

In a separate published Nov. 25 in Science, Xu and his collaborators found new magnetic properties in moir茅 superlattices formed by ultrathin sheets of chromium triiodide. Unlike the tungsten diselenide and tungsten disulfide, chromium triiodide harbors intrinsic magnetic properties, even as a single atomic sheet. Stacked chromium triiodide layers formed alternating magnetic domains: one that is ferromagnetic 鈥斅爓ith spins all aligned in the same direction 鈥斅燼nd another that is 鈥渁ntiferromagnetic,鈥� where spins point in opposite directions between adjacent layers of the superlattice and essentially 鈥渃ancel each other out,鈥� according to Xu. That discovery also illuminates relationships between a material鈥檚 structure and its magnetism that could propel future advances in computing, data storage and other fields.

鈥淚t shows you the magnetic 鈥榮urprises鈥� that can be hiding within moir茅 superlattices formed by 2D quantum materials,鈥� said Xu. 鈥淵ou can never be sure what you鈥檒l find unless you look.鈥�

First author of the Nature paper is Xi Wang, a UW postdoctoral researcher in physics and chemistry. Other co-authors are Chengxin Xiao at the University of Hong Kong; UW physics doctoral students Heonjoon Park and Jiayi Zhu; Chong Wang, a UW researcher in materials science and engineering; Takashi Taniguchi and Kenji Watanabe at the National Institute for Materials Science in Japan; and Jiaqiang Yan at the Oak Ridge National Laboratory. The research was funded by the U.S. Department of Energy; the U.S. Army Research Office; the U.S. National Science Foundation; the Croucher Foundation; the University Grant Committee/Research Grants Council of Hong Kong Special Administrative Region; the Japanese Ministry of Education, Culture, Sports, Science and Technology; the Japan Society for the Promotion of Science; the Japan Science and Technology Agency; the state of Washington; and the UW.

For more information, contact Xu at xuxd@uw.edu.

The National Science Foundation on Sept. 9 it will fund a new endeavor to bring atomic-level precision to the devices and technologies that underpin much of modern life, and will transform fields like information technology in the decades to come. The five-year, $25 million Science and Technology Center grant will found the 鈥� or IMOD 鈥� a collaboration of scientists and engineers at 11 universities led by the 天美影视传媒.

IMOD research will center on new semiconductor materials and scalable manufacturing processes for new optoelectronic devices for applications ranging from displays and sensors to a technological revolution, under development today, that鈥檚 based on harnessing the principles of quantum mechanics.

鈥淚n the early days of electronics, a computer would fill an entire room. Now we all carry around smartphones that are millions of times more powerful in our pockets,鈥� said IMOD director , the Alvin L. and Verla R. Kwiram Endowed Professor of Chemistry at the UW, chief scientist at the UW and co-director of .聽 鈥淭oday, we see an opportunity for advances in materials and scalable manufacturing to do the same thing for optoelectronics: Can we take a quantum optics experiment that fills an entire room, and fit thousands 鈥� or even millions 聽鈥� of them on a chip, enabling a new revolution? Along the way we anticipate IMOD鈥檚 science will help with a few more familiar challenges, like improving the display of the cell phone you already have in your pocket so the battery lasts longer.鈥�

Optoelectronics is a field that enables much of modern information technology, clean energy, sensing and security. Optoelectronic devices are driven by the interaction of light with electronic materials, typically semiconductors. Devices based on optoelectronics include light-emitting diodes, semiconductor lasers, image sensors and the building blocks of quantum communication and computing technologies such as single-photon sources. Their applications today include sensors, displays and data transmission, and optoelectronics is poised to play a critical role in the development of quantum information systems.

But to realize this quantum future, present-day research must develop new materials and new strategies to manufacture them. That鈥檚 where IMOD comes in, Ginger said. Building on advances in the synthesis of semiconductor and , the center will integrate the work of scientists and engineers from diverse backgrounds, including:

• Chemists with expertise in atomically precise colloidal synthesis, characterization and theory, which consist of engineered systems of nanoparticles suspended in a medium
• Materials scientists and mechanical engineers developing methods for the integration, processing and additive manufacturing of semiconductor devices
• Electrical engineers and physicists who are developing new nanoscale photonic structures and investigating the performance limits of these materials for optical quantum communication and computing

鈥淣SF Science and Technology Centers are integrative not only in the sense that they span traditional academic disciplines, but also in the sense that they seek to benefit society by connecting academic research with industrial and governmental needs, while also educating a diverse STEM workforce,鈥� said Ginger. 鈥淭o this end, we鈥檙e extremely lucky to have had the support of an amazing list of external partners across the fields of industry, government and education.鈥�

A partial list of IMOD鈥檚 external partners includes companies such as Amazon, Applied Materials, Corning Incorporated, Microsoft, Nanosys and FOM Technologies, Inc.; government organizations like the National Renewable Energy Laboratory, the Pacific Northwest National Laboratory and the Washington State Department of Commerce; and educational partners including at UW, and the at Georgia Tech.

The center will launch a series of mentorship, team science training and internship programs for participants, including students from underrepresented groups in STEM and first-generation students. Center scientists will also work with high school teachers on curriculum development programs aligned with the and act as 鈥渁mbassadors鈥� to K-12 students, introducing them to STEM careers.

鈥淚n partnership with and the , IMOD is launching a Quantum Training Testbed facility to provide cutting edge training and workforce development opportunities for students from across IMOD鈥檚 participating sites and partners,鈥� said , associate professor of physics and of electrical and computer engineering at the UW, who is IMOD鈥檚 associate director of quantum workforce development. 鈥淲e鈥檙e excited to have such strong support from our partners in the region, allowing us to build on the investments that Washington state has already made in the to support workforce training and economic development. For example, Microsoft plans to donate a cryostat that will allow our students to cool samples down to within a few degrees of absolute zero to study phenomena such as quantum spin physics and decoherence, and we have plans to do so much more for our trainees. Right now, we鈥檙e asking the question: 鈥榃hat is the equipment we wish we had been able to experiment with as students?鈥欌��

The 11 academic institutions that make up IMOD are the 天美影视传媒; the University of Maryland, College Park; the University of Pennsylvania; Lehigh University; Columbia University; Georgia Institute of Technology; Northwestern University; the City College of New York; the University of Chicago; University of Colorado at Boulder; and the University of Maryland, Baltimore County.

In addition to Ginger and Fu, other UW faculty involved with IMOD include , a UW professor of chemistry; , associate professor of mechanical engineering and of materials science and engineering, and technical director of the Washington Clean Energy Testbeds; , associate professor of physics and of electrical and computer engineering; and , professor of chemistry and director of the Molecular Engineering Materials Center. Fu and Majumdar co-chair and are also faculty members with the UW . Ginger, Cossairt, Fu, MacKenzie and Gamelin are member faculty at the Clean Energy Institute. Ginger, Fu, Majumdar and Gamelin are faculty researchers with the UW .

For more information, contact Ginger at dginger@uw.edu.

Twenty scientists and engineers at the 天美影视传媒 are among the 38 new members elected to the Washington State Academy of Sciences for 2021, according to a July 15 . New members were chosen for 鈥渢heir outstanding record of scientific and technical achievement, and their willingness to work on behalf of the Academy to bring the best available science to bear on issues within the state of Washington.鈥�

Current academy members selected 29 of the new members. An additional nine were elected by virtue of joining one of the National Academies.

New UW members who were elected by current academy members are:

• , professor and Port of Tacoma Chair in Environmental Science at UW Tacoma, director of the and science director of the , 鈥渇or foundational work on the environmental fate, behavior and toxicity of PCBs.鈥�
• , professor of psychology, 鈥渇or contributions in research on racial and gender inequality that has influenced practices in education, government, and business鈥� and 鈥渇or shifting the explanation for inequality away from individual deficiencies and examining how societal stereotypes and structures cause inequalities.鈥�
• , professor of chemistry and member faculty at the , 鈥渇or leadership in the innovative synthesis and chemical modification of nanoscale materials for application in light emission and catalysis.鈥�
• , professor of global health and of environmental and occupational health sciences, and founding director of the , 鈥渇or work on the health impacts of climate change, on climate impact forecasting, on adaptation to climate change and on climate policy to protect health.鈥�
• , professor of environmental and forest sciences and dean emeritus of the College of the Environment, 鈥渇or foundational studies of regional paleoenvironmental history and sustained excellence in academic leadership to catalyze and sustain transformative research and educational initiatives.鈥� Graumlich is also president-elect of the American Geophysical Union.
• Dr. , the Joseph W. Eschbach Endowed Chair in Kidney Research and co-director of the , 鈥渇or pioneering contributions and outstanding achievements in the development of the novel wearable artificial kidney, as well as numerous investigator-initiated clinical trials and multi-center collaborative studies.鈥�
• , professor of environmental chemistry and chair of the Physical Sciences Division at UW Bothell, 鈥渇or leadership in monitoring and understanding the global transport of atmospheric pollutants from energy production, wildfire, and other sources, as well as science communication and service that has informed citizens and enhanced public policy.鈥�
• , professor and chair of psychology, 鈥渇or contributions demonstrating how psychological science can inform long-standing issues about racial and gender discrimination鈥� and 鈥渇or research that has deep and penetrating implications for the law and societal efforts to remedy social inequities with evidence-based programs and actions.鈥�
• , the Leon C. Johnson Professor of Chemistry, member faculty at the and chair of the Department of Chemistry, 鈥渇or developing new spectroscopy tools for measuring energy flow in molecules and materials with high spatial and temporal resolution.鈥�
• , professor of astronomy, 鈥渇or founding the and leading the decades-long development of the interdisciplinary modeling framework and community needed to establish the science of exoplanet astrobiology鈥� and 鈥渇or training the next generation of interdisciplinary scientists who will search for life beyond Earth.鈥�
• , professor and chair of aeronautics and astronautics, 鈥渇or leadership and significant advances in nonlinear methods for integrated sensing and control in engineered, bioinspired and biological flight systems鈥� and 鈥渇or leadership in cross-disciplinary aerospace workforce development.鈥�
• , associate professor of chemistry and member faculty with the Molecular Engineering and Sciences Institute, 鈥渇or exceptional contributions to the development of synthetic polymers and nanomaterials for self-assembly and advanced manufacturing with application in sustainability, medicine and microelectronics.鈥�
• Dr. , Associate Dean of Medical Technology Innovation in the College of Engineering and the School of Medicine, the Graham and Brenda Siddall Endowed Chair in Cornea Research, and medical director of the UW Eye Institute, 鈥渇or developing and providing first class clinical treatment of severe corneal blindness to hundreds of people, for establishing the world premier artificial cornea program in Washington, and for leading collaborative research to translate innovative engineering technologies into creative clinical solution.鈥�
• Dr. , professor of medicine and director of the , 鈥渇or global recognition as an authority on drug and vaccine development for viral and parasitic diseases through work as an infectious disease physician and immunologist.鈥�
• Dr. , professor of pediatrics and of anesthesiology and pain medicine, and director of the , 鈥渇or outstanding leadership in pediatric anesthesiology and in the care of children with traumatic brain injury鈥� and 鈥渇or internationally recognized expertise in traumatic brain injury and direction of the Harborview Injury Prevention and Research Center for the last decade as an exceptional mentor and visionary leader.鈥�

UW members who will join the Washington State Academy of Sciences by virtue of their election to one of the National Academies are:

• , professor of biostatistics, 鈥渇or the development of novel statistical models for longitudinal data to better diagnose disease, track its trajectory, and predict its outcomes鈥� and 鈥渇or revolutionizing how dynamic predictors are judged by their discrimination and calibration and has significantly advanced methods for randomized controlled trials.鈥� Heagerty was elected to the National Academy of Medicine in 2021.
• , the Bill and Melinda Gates Chair in Computer Science and Engineering, 鈥渇or foundational contributions to the mathematics of computer systems and of the internet, as well as to the design and probabilistic analysis of algorithms, especially on-line algorithms, and algorithmic mechanism design and game theory.鈥� Karlin was elected to the National Academy of Sciences in 2021.
• , professor emeritus of applied mathematics and data science fellow at the , 鈥渇or inventing key algorithms for hyperbolic conservation laws and transforming them into powerful numerical technologies鈥� and 鈥渇or creating the Clawpack package, which underpins a wide range of application codes in everyday use, such as for hazard assessment due to tsunamis and other geophysical phenomena.鈥� LeVeque was elected to the National Academy of Sciences in 2021.
• , the Benjamin D. Hall Endowed Chair in Basic Life Sciences and an investigator with the Howard Hughes Medical Institute, 鈥渇or advancing our physical understanding of cell motility and growth in animals and bacteria鈥� and 鈥渇or discovering how the pathogen Listeria uses actin polymerization to move inside human cells, how crawling animal cells coordinate actomyosin dynamics and the mechanical basis of size control and daughter cell separation in bacteria.鈥� Theriot was elected to the National Academy of Sciences in 2021.
• , professor and chair of biological structure, 鈥渇or elucidating cellular transformations through which neurons pattern their dendrites, and the interplay of activity-dependent and -independent mechanisms leading to assembly of stereotyped circuits鈥� and 鈥渇or revelations regarding the fundamental principles of neuronal development through the application of an elegant combination of in vivo imaging, physiology, ultrastructure and genetics to the vertebrate retina.鈥� Wong was elected to the National Academy of Sciences in 2021.

New members to the Washington State Academy of Sciences are scheduled to be inducted at a meeting in September.

There are two major hurdles to overcome on the road to laboratory-grown organs and tissues. The first is to use a biologically compatible 3D scaffold in which cells can grow. The second is to decorate that scaffold with biochemical messages in the correct configuration to trigger the formation of the desired organ or tissue.

In a major step toward transforming this hope into reality, researchers at the 天美影视传媒 have developed a technique to modify naturally occurring biological polymers with protein-based biochemical messages that affect cell behavior. Their approach, published the week of Jan. 18 in the Proceedings of the National Academy of Sciences, uses a near-infrared laser to trigger chemical adhesion of protein messages to a scaffold made from biological polymers such as collagen, a connective tissue found throughout our bodies.

Mammalian cells responded as expected to the adhered protein signals within the 3D scaffold, according to senior author , a UW associate professor of chemical engineering and of bioengineering. The proteins on these biological scaffolds triggered changes to messaging pathways within the cells that affect cell growth, signaling and other behaviors.

These methods could form the basis of biologically based scaffolds that might one day make functional laboratory-grown tissues a reality, said DeForest, who is also a faculty member with the UW and the UW .

鈥淭his approach provides us with the opportunities we鈥檝e been waiting for to exert greater control over cell function and fate in naturally derived biomaterials 鈥� not just in three-dimensional space but also over time,鈥� said DeForest. 鈥淢oreover, it makes use of exceptionally precise photochemistries that can be controlled in 4D while uniquely preserving protein function and bioactivity.鈥�

DeForest鈥檚 colleagues on this project are lead author Ivan Batalov, a former UW postdoctoral researcher in chemical engineering and bioengineering, and co-author , a UW assistant professor of bioengineering and of laboratory medicine and pathology.

Their method is a first for the field, spatially controlling cell function inside naturally occurring biological materials as opposed to those that are synthetically derived. Several research groups, including DeForest鈥檚, have developed light-based methods to modify synthetic scaffolds with protein signals. But natural biological polymers can be a more attractive scaffold for tissue engineering because they innately possess biochemical characteristics that cells rely on for structure, communication and other purposes.

鈥淎 natural biomaterial like collagen inherently includes many of the same signaling cues as those found in native tissue,鈥� said DeForest. 鈥淚n many cases, these types of materials keep cells 鈥榟appier鈥� by providing them with similar signals to those they would encounter in the body.鈥�

They worked with two types of biological polymers: collagen and fibrin, a protein involved in blood clotting. They assembled each into fluid-filled scaffolds known as hydrogels.

The signals that the team added to the hydrogels are proteins, one of the main messengers for cells. Proteins come in many forms, all with their own unique chemical properties. As a result, the researchers designed their system to employ a universal mechanism to attach proteins to a hydrogel 鈥� the binding between two chemical groups, an alkoxyamine and an aldehyde. Prior to hydrogel assembly, they decorated the collagen or fibrin precursors with alkoxyamine groups, all physically blocked with a 鈥渃age鈥� to prevent the alkoxyamines from reacting prematurely. The cage can be removed with ultraviolet light or a near-infrared laser.

Using methods previously developed in DeForest鈥檚 laboratory, the researchers also installed aldehyde groups to one end of the proteins they wanted to attach to the hydrogels. They then combined the aldehyde-bearing proteins with the alkoxyamine-coated hydrogels, and used a brief pulse of light to remove the cage covering the alkoxyamine. The exposed alkoxyamine readily reacted with the aldehyde group on the proteins, tethering them within the hydrogel. The team used masks with patterns cut into them, as well as changes to the laser scan geometries, to create intricate patterns of protein arrangements in the hydrogel 鈥� including an old UW logo, Seattle鈥檚 Space Needle, a monster and the 3D layout of the human heart.

The tethered proteins were fully functional, delivering desired signals to cells. Rat liver cells 鈥� when loaded onto collagen hydrogels bearing a protein called EGF, which promotes cell growth 鈥� showed signs of DNA replication and cell division. In a separate experiment, the researchers decorated a fibrin hydrogel with patterns of a protein called Delta-1, which activates a specific pathway in cells called Notch signaling. When they introduced human bone cancer cells into the hydrogel, cells in the Delta-1-patterned regions activated Notch signaling, while cells in areas without Delta-1 did not.

These experiments with multiple biological scaffolds and protein signals indicate that their approach could work for almost any type of protein signal and biomaterial system, DeForest said.

鈥淣ow we can start to create hydrogel scaffolds with many different signals, utilizing our understanding of cell signaling in response to specific protein combinations to modulate critical biological function in time and space,鈥� he added.

With more-complex signals loaded on to hydrogels, scientists could then try to control stem cell differentiation, a key step in turning science fiction into science fact.

The research was funded by the National Science Foundation, the National Institutes of Health and Gree Real Estate.

For more information, contact DeForest at profcole@uw.edu.

Nanoparticles are a promising type of drug delivery system. Also known as nanocarriers, these tiny particles can bind to drugs and protect them from degradation until they enter tumor cells. But their effectiveness as drug carriers and drug protectors, as well as potential toxicity in patients, depends significantly on their size, composition and chemical properties. Balancing these competing factors is a delicate process. Although researchers have made significant advances in nanomedicine in the last decade, it remained a formidable challenge to design and synthesize small, stable nanoparticles that could deliver sufficient drugs to treat solid tumors.

Earlier this year scientists at the 天美影视传媒 announced that they have achieved such a balancing act with a nanoparticle-based drug delivery system that can ferry a potent anti-cancer drug through the bloodstream safely. As they report in a published in May in Materials Today, their nanoparticle is derived from , a natural and organic polymer that, among other things, makes up the outer shells of shrimp.

The team, led by , a UW professor of materials science and engineering and of neurological surgery, demonstrated that their chitin-derived system can successfully ferry , a potent anti-cancer drug that is also known as paclitaxel, through the bloodstream and inhibit tumor growth and spread, also known as metastasis, in mice. The nanoparticles showed no adverse side effects, likely since they are derived in part from naturally occurring polymer.

鈥淭his could form the basis of a new class of nanoparticle delivery systems that can transport anti-cancer therapeutics through the body safely, with no toxic side effects from the nanoparticle material,鈥� said Zhang, who is also a faculty researcher with the UW and the .

The nanoparticles, once loaded with Taxol, are about 20.6 nanometers in diameter. That鈥檚 about 1/4000th the width of a human hair, the U.S. National Nanotechnology Initiative. The particles are small enough to travel through blood vessels and get to potentially compact tumor sites.

Zhang鈥檚 team started by loading Taxol particles onto much longer strands of , a material derived from chitin. The nanofibers break down to form nanoparticles when exposed to serum, a blood protein, either in the lab or in the body. Researchers showed that drug-loaded nanofibers, when injected into mice, broke down rapidly into the tiny nanoparticles 鈥� thanks to serum proteins in the blood 鈥� and could circulate freely in the bloodstream, enter organs and reach tumor sites.

The team subjected Taxol-loaded nanoparticles to a barrage of experiments to see what they could do to tumors. In cell cultures of mouse mammary cancer cells, a majority of cancer cells showed signs of cell death 48 hours after treatment, indicating that nanoparticle-associated Taxol could enter cancer cells and impair cell growth at least as well as free-floating Taxol. In mice, Taxol-loaded nanofibers, which broke down into nanoparticles, showed 90% inhibition of mammary tumor growth compared to about 66% inhibition for Taxol injected in the clinical solution used widely today. The nanoparticles also inhibited melanoma tumor growth in mice by up to 75%. In separate experiments in mice, Taxol-loaded nanoparticles also prevented spread of mammary cancer to other parts of the body, unlike Taxol in a clinical solution.

In addition to these promising findings with tumors, the team found that the nanoparticles kept Taxol circulating in the bloodstream longer, giving the drug more time to reach the tumor site. In the bloodstream of mice, the half-life of Taxol-associated nanoparticles was nearly 25 hours, compared to less than 2 hours for Taxol injected in the clinical solution. Mice injected with the nanofibers showed no signs of toxic side effects, indicating that the nanoparticles themselves weren鈥檛 causing harm to tissues. In contrast, the clinical solution used widely today for Taxol can cause liver toxicity in mice, among other side effects.

Zhang believes that the chitosan-derived nanoparticles could form the basis of a non-toxic drug delivery system for cancer that keeps therapeutics in the body longer to inhibit tumor growth and metastasis.

鈥淭his is a very promising finding. Many drug delivery systems used today for anti-cancer drugs come with toxic side effects, and don鈥檛 protect the drug for very long in the patient鈥檚 body,鈥� said Zhang. 鈥淭he nanoparticles have all the characteristics you could hope for in getting the drug to into tumor cells. The small chitosan-based nanocarrier, made in situ, with unique biocompatibility and biodegradability, offers a new strategy for anti-cancer drug delivery and has great potential for rapid translation to the clinic.鈥�

Co-authors on the paper are Qingxin Mu, Guanyou Lin, Zachary Stephen, Seokhwan Chung and Hui Wang in the UW Department of Materials Science & Engineering; Victoria Patton in the UW Department of Chemical Engineering; and Rachel Gebhart in the UW Department of Chemistry. The research was funded by the National Institutes of Health and the National Science Foundation.

For more information, contact Zhang at mzhang@uw.edu.