Tag Archives: Jianyu Li

Peptide-based hydrogels for faster healing from research team at the University of Ottawa

While this research team was heavily dominated by researchers from the University of Ottawa, there were two members associated with the University of Talca (Universidad de Talca; located in Chile), two members associated with the University of Montreal (Université de Montréal), and one member with McGill University (located in Montréal).

Now for these special hydrogels, from a May 13, 2024 University of Ottawa news release (also on EurekAlert) by David McFadden, Note: Links have been removed,

Combining biomedical finesse and nature-inspired engineering, a uOttawa-led team of scientists have created a jelly-like material that shows great potential for on-the-spot repair to a remarkable range of damaged organs and tissues in the human body.

Cutting-edge research co-led by uOttawa Faculty of Medicine  Associate Professor Dr. Emilio I. Alarcón could eventually impact millions of lives with peptide-based hydrogels that will close skin wounds, deliver therapeutics to damaged heart muscle, as well as reshape and heal injured corneas.

“We are using peptides to fabricate therapeutic solutions. The team is drawing inspiration from nature to develop simple solutions for wound closure and tissue repair,” says Dr. Alarcón, a scientist and director at the BioEngineering and Therapeutic Solutions (BEaTS) group at the University of Ottawa Heart Institutek whose innovative research work is focused on developing new materials with capabilities for tissue regeneration.

Peptides are molecules in living organisms and hydrogels are a water-based material with a gelatinous texture that have proven useful in therapeutics.

The approach used in the study –  just published in Advanced Functional Materials and co-led by Dr. Erik Suuronen & Dr. Marc Ruel – is unique. Most hydrogels explored in tissue engineering are animal-derived and protein-based materials, but the biomaterial created by the collaborative team is supercharged by engineered peptides. This makes it more clinically translatable.

Dr. Ruel, a full professor in the uOttawa Faculty of Medicine’s Department of Cellular and Molecular Medicine and the endowed chair of research in the Division of Cardiac Surgery at the University of Ottawa Heart Institute, says the study’s insights could be a game changer.

“Despite millennia of evolution, the human response to wound healing still remains imperfect,” Dr. Ruel says. “We see maladapted scarring in everything from skin incisions to eye injuries, to heart repair after a myocardial infarction. Drs. Alarcón, Suuronen, and the rest of our team have focused on this problem for almost two decades. The publication by Dr. Alarcón in Advanced Functional Materials reveals a novel way to make wound healing, organ healing, and even basic scarring after surgery much more therapeutically modulatable and, therefore, optimizable for human health.”

Indeed, the ability to modulate the peptide-based biomaterial is key. The uOttawa-led team’s hydrogels are designed to be customizable, making the durable material adaptable for use in a surprising range of tissues. Essentially, the two-component recipe could be adjusted to ramp up adhesivity or dial down other components depending on the part of the body needing repair.

“We were in fact very surprised by the range of applications our materials can achieve,” says Dr. Alarcón. “Our technology offers an integrated solution that is customizable depending on the targeted tissue.”

Dr. Alarcón says that not only does the study’s data suggest that the therapeutic action of the biomimetic hydrogels are highly effective, but its application is far simpler and cost-effective than other regenerative approaches.

The materials are engineered in a low-cost and scalable manner – hugely important qualities for any number of major biomedical applications. The team also devised a rapid-screening system that allowed them to significantly slash the design costs and testing timespans.

“This significant reduction in cost and time not only makes our material more economically viable but also accelerates its potential for clinical use,” Dr. Alarcón says.

What are next steps for the talent-rich research team? They will conduct large animal tests in preparation for tests in human subjects. So far, heart and skin tests were conducted with rodents, and the cornea work was done ex vivo.

Part of the work for this study was funded by the uOttawa Faculty of Medicine’s  “Path to Patenting & Pre-Commercialization” (3P),  an innovation-focused approach to provide our community’s top-flight researchers with the assistance needed to bring their most promising breakthroughs to the wider world.

Here’s a link to and a citation for the paper,

Multipurpose On-the-Spot Peptide-Based Hydrogels for Skin, Cornea, and Heart Repair by Alex Ross, Xixi Guo, German A. Mercado Salazar, Sergio David Garcia Schejtman, Jinane El-Hage, Maxime Comtois-Bona, Aidan Macadam, Irene Guzman-Soto, Hiroki Takaya, Kevin Hu, Bryan Liu, Ryan Tu, Bilal Siddiqi, Erica Anderson, Marcelo Muñoz, Patricio Briones-Rebolledo, Tianqin Ning, May Griffith, Benjamin Rotsein, Horacio Poblete, Jianyu Li, Marc Ruel, Erik J. Suuronen, Emilio I. Alarcon. Advanced Functional Materials DOI: https://doi.org/10.1002/adfm.202402564 First published: 23 April 2024

This paper is open access.

Making longer lasting bandages with sound and bubbles

This research into longer lasting bandages described in an August 12, 2022 news item on phys.org comes from McGill University (Montréal, Canada)

Researchers have discovered that they can control the stickiness of adhesive bandages using ultrasound waves and bubbles. This breakthrough could lead to new advances in medical adhesives, especially in cases where adhesives are difficult to apply such as on wet skin.

“Bandages, glues, and stickers are common bioadhesives that are used at home or in clinics. However, they don’t usually adhere well on wet skin. It’s also challenging to control where they are applied and the strength and duration of the formed adhesion,” says McGill University Professor Jianyu Li, who led the research team of engineers, physicists, chemists, and clinicians.

Caption: Adhesive hydrogel applied on skin under ultrasound probe. Credit: Ran Huo and Jianyu Li

An August 12, 2022 McGill University news release (also on EurekAlert), which originated the news item, delves further into the work,

“We were surprised to find that by simply playing around with ultrasonic intensity, we can control very precisely the stickiness of adhesive bandages on many tissues,” says lead author Zhenwei Ma, a former student of Professor Li and now a Killam Postdoctoral Fellow at the University of British Columbia.

Ultrasound induced bubbles control stickiness

In collaboration with physicists Professor Outi Supponen and Claire Bourquard from the Institute of Fluid Dynamics at ETH Zurich, the team experimented with ultrasound induced microbubbles to make adhesives stickier. “The ultrasound induces many microbubbles, which transiently push the adhesives into the skin for stronger bioadhesion,” says Professor Supponen. “We can even use theoretical modeling to estimate exactly where the adhesion will happen.”

Their study, published in the journal Science, shows that the adhesives are compatible with living tissue in rats. The adhesives can also potentially be used to deliver drugs through the skin. “This paradigm-shifting technology will have great implications in many branches of medicine,” says University of British Columbia Professor Zu-hua Gao. “We’re very excited to translate this technology for applications in clinics for tissue repair, cancer therapy, and precision medicine.”

“By merging mechanics, materials and biomedical engineering, we envision the broad impact of our bioadhesive technology in wearable devices, wound management, and regenerative medicine,” says Professor Li, who is also a Canada Research Chair in Biomaterials and Musculoskeletal Health.

Here’s a link to and a citation for the paper,

Controlled tough bioadhesion mediated by ultrasound by Zhenwei Ma, Claire Bourquard, Qiman Gao, Shuaibing Jiang, Tristan De Iure-Grimmel, Ran Huo, Xuan Li, Zixin He, Zhen Yang, Galen Yang, Yixiang Wang, Edmond Lam, Zu-hua Gao, Outi Supponen and Jianyu Li. Science 11 Aug 2022 Vol 377, Issue 6607 pp. 751-755 DOI: 10.1126/science.abn8699

This paper is behind a paywall.

I haven’t seen this before but it seems that one of the journal’s editors decided to add a standalone paragraph to hype some of the other papers about adhesives in the issue,

A sound way to make it stick

Tissue adhesives play a role in temporary or permanent tissue repair, wound management, and the attachment of wearable electronics. However, it can be challenging to tailor the adhesive strength to ensure reversibility when desired and to maintain permeability. Ma et al. designed hydrogels made of polyacrylamide or poly(N-isopropylacrylamide) combined with alginate that are primed using a solution containing nanoparticles of chitosan, gelatin, or cellulose nanocrystals (see the Perspective by Es Sayed and Kamperman). The application of ultrasound causes cavitation that pushes the primer molecules into the tissue. The mechanical interlocking of the anchors eventually results in strong adhesion between hydrogel and tissue without the need for chemical bonding. Tests on porcine or rat skin showed enhanced adhesion energy and interfacial fatigue resistance with on-demand detachment. —MSL

I like the wordplay and am guessing that MSL is:

Marc S. Lavine
Senior Editor
Education: BASc, University of Toronto; PhD, University of Cambridge
Areas of responsibility: Reviews; materials science, biomaterials, engineering