Symposium SB06: Peptide and Protein-Based Materials

Written by Richard Wu

David Baker, the University of Washington 

The Coming of Age of De Novo Protein Design 

Life on Earth depends on proteins. Proteins are large molecules assembled from building blocks, called amino acids, and are produced through a folding process that results in a complex three-dimensional structure, like origami. There are many different amino acids, each with particular properties such as size and charge, and the sequence of amino acids in a protein determines its structure and function.

However, given the complexity of proteins, it is difficult to predict protein structures from amino acid sequences alone. David Baker from the University of Washington is studying protein-folding and designing algorithms to predict protein structures. His laboratory has harnessed artificial intelligence to develop RoseTTAFold, a software tool that computes protein structures from amino acid sequences. From there, they have also worked on software approaches to generate new amino acid sequences which could fold into desired protein structures.

Baker’s research has led to the design of various artificial proteins that can block the flu and COVID-19 viruses, prevent the formation of Alzheimer’s disease-associated proteins, harvest sunlight for energy, produce light, and self-assemble into geometrically-shaped nanostructures. The design of artificial proteins is an exciting step forward in science, with the potential to transform numerous fields ranging from medicine to energy.

 

Ebru Demir, Sabanci University 

Self-Assembling Peptide Nanofiber Hydrogel as 3D Scaffolds for Corneal Stromal Cells 

Severe damage to the cornea of the eye, which can lead to visual impairment or blindness, is often treated with corneal transplantation. However, corneal transplantation is limited by donor tissue availability.

One alternative to corneal transplantation is tissue engineering. Ebru Demir from Sabanxci University has been investigating the use of peptide-based hydrogels as scaffolds for corneal tissue engineering. These hydrogels are gel-like materials containing water, similar to gelatin, and are synthesized from peptide materials, which are made from the same building blocks as proteins.

Demir’s experiments show that the peptide-based hydrogels are biocompatible, have similar transparency to natural corneal tissue, and are strong enough to support corneal cell and blood vessel regeneration. These properties make the peptide-based hydrogels a good candidate material for use in corneal tissue scaffolds.

Through this work, Demir and colleagues demonstrate how materials research can help advance the field of tissue engineering, thereby making steps toward improving human health and well-being.

 

Mohamed Soliman, De Montfort University and Cairo University 

Antimicrobial Activity of β-Sheet Forming Ultra-Short De Novo Ionic-Complementary Peptides Towards Wound Infections 

A significant problem facing medicine today is the rise of bacterial resistance to antibiotics. To address this public health challenge, Mohamed Soliman, from De Montfort University and Cairo University, is researching the antimicrobial properties of peptide-based hydrogels. Peptide materials are made from the same building blocks as proteins, and hydrogels are gel-like materials that contain water, similar to gelatin. These peptide-based hydrogel materials can kill bacteria by puncturing bacterial cell membranes, and yet are biocompatible and biodegradable.

Soliman and colleagues have found that their peptide-based hydrogels were effective at killing multiple infectious bacteria species, including P. aeruginosa, A. baumannii, E. coli, and K. Pneumoniae. These findings are promising and suggest that antimicrobial peptide-based hydrogels could soon help save lives.

Symposium SB05: Nano-Bio Interactions—From Design to Biological Response

Sebastien Perrier, the University of Warwick and Monash University 

Cyclic Peptide/Polymer Conjugates for Therapeutic Applications 

Written by Richard Wu

Peptides are small molecular assemblies made up from the same building blocks as proteins. While most peptides are naturally occurring, synthetic peptide materials have recently become a topic of research interest for various biomedical applications.

Sebastien Perrier, from the University of Warwick and Monash University, has been experimenting with using peptides to build nanotubes for therapeutic purposes. By chemically attaching small polymer materials to peptides, his research group has been able to develop self-assembling nanotubes. These nanotubes can deliver anti-cancer drugs to kill tumor cells and be degraded easily when exposed to a certain wavelength of light. In animal studies, the nanotubes were well-tolerated and could be excreted quickly through the kidneys, demonstrating that they did not accumulate in the body or cause toxicity.

These findings have the potential to advance cancer treatments that can more specifically target tumor cells and be better tolerated by the human body. In doing so, this work makes important steps toward improving the lives of cancer patients. 

Symposium SF04: Development and Design of Responsive Architected Materials

Luis Rodriguez Alfaro, Autonomous University of Nuevo Leon 

Design of Solar-Driven Self-Cleaning and Antimicrobial Magnesium Oxychloride Cement Panels

Written by Richard Wu

Photocatalytic materials, which are materials that use light to facilitate a chemical reaction, have drawn interest in construction due to their potential to help reduce air pollution, dirt accumulation, and bacterial growth on the surfaces of building structures.

Luis Rodriguez Alfaro from the Autonomous University of Nuevo Leon has been developing smart cement material alternatives to the Portland cement commonly used in construction today. His research group has been studying magnesium oxychloride cement (MOC), which is more environmentally friendly, mechanically stronger, more fire-resistant, and a better insulator than conventional Portland cement. By embedding the MOC with photocatalytic titanium dioxide (TiO₂) nanoparticles, the researchers have produced a cement that has self-cleaning properties when exposed to sunlight. Their experiments show that when exposed to sunlight, the MOC with TiO₂ nanoparticles was able to self-clean several different chemical pollutants and inhibit growth of E. coli bacteria.

While this work is still in progress, it shows that MOC with TiO₂ nanoparticles has a lot of promise as a smart construction material. With its self-cleaning and antibacterial properties, the MOC with TiO₂ nanoparticles could soon be used to construct cleaner buildings and cities. 

Symposium SB05: Nano-Bio Interactions—From Design to Biological Response

Thomas J. Webster, Hebei University of Technology and Saveetha University

Commercializing Nano Implants—Real Human Clinical Evidence of Success in the Spine 

Written by Richard Wu

Nanomaterials have shown promise for facilitating tissue growth, resisting infection, reducing inflammation, and killing cancer cells. However, most nanomaterials under scientific investigation have not yet made it to the market as viable commercial products.

Thomas J. Webster, from Hebei University of Technology and Saveetha University, has been designing, testing, and marketing surgical implants that utilize nanomaterial technology. His work has found that orthopedic implants can be treated through various processes to form nanoscale surface textures on the implants. These nanotextures mimic the nanoscale surface texture of bone, and not only reduce inflammation, but also inhibit growth of common infectious bacteria—including S. aureus, P. aeruginosa, and ampicillin-resistant E. coli—without antibiotics.

In rat studies, Webster’s research group found that rats with nanotextured implants had improved surgical recovery with reduced bacterial colonization compared to those in a control group. Subsequent human studies had similar findings—in 14,000 patients who received nanotextured titanium screw implants during orthopedic surgery, none developed screw failure, and in 4,000 patients who received nanotextured silicon nitride orthopedic implants, none developed implant failure. Webster’s findings pave the way for future applications of nanomaterials in biomedical devices.

Symposium SB01: Fundamentals and Applications of Engineered Living Materials

Kumba Bonga, the University of Genoa and the Italian Institute of Technology 

Fabricating Mycelium-Agrowaste 3D Composite Materials for Use in Building Construction Insulation 

Written by Richard Wu

Over a third of worldwide carbon emissions today are due to the construction industry. Recent efforts to make construction materials more sustainable have focused on renewable materials such as biomaterials for environmentally friendly buildings.

Kumba Bonga, from the University of Genoa and the Italian Institute of Technology, has been investigating the applications of fungal mycelia as a material for building insulation. Mycelium, which is a network of fungal threads, has many desirable properties as a construction material, as it can be grown cheaply from agricultural waste, is biodegradable, and does not leach toxic chemicals into the environment.

Bonga and colleagues have developed a process to grow the fungus Pleurotus ostreatus from agricultural waste such as coffee silverskin pellets, shape the fungal mycelium structure as it grows, and oven-dry to stop fungal growth. The resulting mycelium material exhibited similar insulative properties to conventional building insulation materials and was also found to be water-repellent.

This work shows that fungal mycelium-based materials, which are inexpensive yet sustainable, could make a great alternative for building insulation. As it turns out, mushrooms can be useful for more than just food!

Symposium SB05: Nano-Bio Interactions—From Design to Biological Response

Nguyen T.K. Thanh, University College London 

Plasmonic and Magnetic Nanoparticles for Biomedical Application 

Written by Richard Wu 

Nanoparticles, which are tiny particles between 1-100 nm in size, are attracting interest in biomedical research for their unusual properties. Nguyen Thanh from University College London has been investigating various clinical applications for nanoparticles. 

One use for nanoparticles is sterilizing hospital surfaces and items. Thanh’s research group has found that gold nanoparticles can be combined with a light-sensitive dye to kill E. coli bacteria in the presence of light. The researchers have also been able to use magnetic nanoparticles to separate pathogenic bacteria from liquids. 

Another application for nanoparticles that Thanh has been studying is cancer therapy. Since cancer cells tend to thrive in acidic environments, pH-sensitive nanoparticles can target cancer cells. These same nanoparticles can also selectively deliver anticancer drugs and treatments to kill tumor cells. 

Yet another clinical use for nanoparticles is medical imaging. Gadolinium, a contrast agent injected into patients to help visualize body structures on medical images, can cause side effects including kidney injury. Thanh’s research group has found that iron oxide nanoparticles could potentially serve as a lower-risk alternative to gadolinium in medical imaging tests. 

While nanoparticles may be small, Thanh’s research makes it clear that nanoparticle research has big implications for improving human health. 

Symposium SB03: Thin-Film Devices, Barriers and Their Reliability

Preeti Tyagi, North Carolina State University 

Exploration of Hemp Hurds Waste for Lignin-Containing Nanocellulose Based-Barrier Films for Sustainable Packaging 

Written by Richard Wu

Non-biodegradable packaging materials, particularly single-use plastics, are everywhere and a significant contributor to the problem of environmental waste. One potential solution could be cellulose nanofibers (CNFs), a type of material produced through mechanical treatment and refinement processes of plant fibers. However, production of CNF materials often requires expensive raw materials such as wood pulp and high energy usage, and the resulting final product tends to be very hydrophilic, meaning it is very sensitive to water and dissolves in water more easily.

Preeti Tyagi from North Carolina State University has been investigating manufacturing methods and materials properties of a new type of CNF called lignin-containing cellulose nanofibers (LCNFs). LCNFs can be produced from inexpensive agricultural waste such as hemp hurds and have a less hydrophilic molecular structure than conventional CNFs. Tyagi’s research group found that these LCNFs were less expensive to produce and displayed greater water resistance than more conventional CNFs, making the LCNFs more suitable for applications such as food packaging.

This research makes important steps toward helping achieve a circular economy, thereby advancing efforts to promote greater sustainability.

Symposium SB03: Thin-Film Devices, Barriers and Their Reliability

Shantanu Nikam, the University of Akron and Duke University 

Anti-Adhesive Bioresorbable Elastomer Coating That Reduce Intraperitoneal Adhesions in Abdominal Repair Procedures 

Written by Richard Wu

Every year, thousands of patients who have abdominal surgeries suffer from intraperitoneal adhesions (IAs), which are bands of excess scar tissue that form between internal organs and the abdominal wall. IAs can mechanically constrict organs such as the intestines, leading to problems such as intestinal blockage, pain, inflammation, and infection. Patients suffering from IA complications often need further surgery and rehospitalization, resulting in further healthcare costs.

Shantanu Nikam, from the University of Akron and Duke University, is designing a solution to help reduce IAs in abdominal hernia repair surgeries. Hernia repair surgeries require implanting a mesh in the body to mechanically support damaged tissue during healing. However, these mesh implants can cause inflammation and scarring within the abdomen, which can lead to IA formation. Nikam’s research group has synthesized a new mesh implant that has a biodegradable coating made from a zwitterionic elastomer material. The coating is formulated to be resistant to IA formation and can withstand mechanical stresses from activities such as coughing, jumping, or stretching. As seen in experiments on rabbits, the coated mesh implants significantly reduced IA extent compared to standard uncoated mesh implants, suggesting that the new mesh implants have potential to reduce surgical complications.

Symposium EL13: Organic Materials and Devices for Neuronal/Neuromorphic Processing, Adaptive Sensing and Actuation

Molly Stevens, Imperial College London 

Designing Bioelectronic Materials for Regenerative Medicine 

Written by Richard Wu 

Polymer materials have many potential biomedical applications. The Stevens Group at Imperial College London, led by Molly Stevens, is developing bioelectronic polymer materials for regenerative medicine and therapeutic uses. Stevens reported methods to chemically modify the molecular structures of various polymers, which has allowed the research group to fine-tune the polymers’ material properties. These modified polymers can exhibit unusual behaviors, such as electrical conductivity, light sensitivity, and self-degradation in response to a stimulus.

Using these bioelectronic polymer materials, the researchers have been working to address a number of important medical challenges. Their work has led to the development of many innovative technologies, including electrically conductive heart patches that could one day help treat heart attack victims, light-responsive biosensors that are able to locate cancer cells, and microrobots that can selectively deliver drugs to cells in the body. Given the number of potential biomedical applications, it is exciting to see how these bioelectronic polymer materials can be used to improve human health and treat disease.

Symposium EL08: Nanogenerators and Piezotronics

Yuljae Cho, University of Michigan–Shanghai Jiao Tong University Joint Institute 

Hybrid Smart Fiber with Spontaneous Self-Charging for Wearable Electronic Applications 

Written by Richard Wu

Wearable electronics, which have become increasingly widespread in recent years, have many potential applications for biomedical devices. However, an important limitation of many wearable electronic devices is the need for an external energy supply, which may not always be available or practical in biomedical applications.

Yuljae Cho, from the University of Michigan–Shanghai Jiao Tong University Joint Institute, has been working to address this need by designing and experimenting on hybrid smart fiber materials which are capable of self-charging. When subjected to mechanical forces such as tugging or pulling, these smart fiber materials can convert the movement into electricity and power a small light. The smart fibers are also quite durable and can endure repeated mechanical stresses, such as from bending, knotting, and even washing.

While this work is still ongoing, the hybrid smart fibers have a lot of potential applications. Thanks to their self-charging properties and durability, these smart fibers may soon be powering the next generation of biomedical devices and other wearable electronics.