Tag Archives: Dan Li

PAINT wound-healing ink into your cuts with a 3D-printing pen

This screams tattoo to me but it’s not,

Caption This 3-D printing pen is painting a gel that can help wounds of all shapes heal quickly and effectively. Credit: Adapted from ACS Applied Materials & Interfaces, 2023, DOI: 10.1021/acsami.3c03630

A June 1, 2023 American Chemical Society (ACS) news release (also on EurekAlert), announces a new approach to wound healing,

The body is pretty good at healing itself, though more severe wounds can require bandages or stitches. But researchers publishing in ACS Applied Materials & Interfaces have developed a wound-healing ink that can actively encourage the body to heal by exposing the cut to immune-system vesicles. The ink can be spread into a cut of any shape using a 3D-printing pen, and in mice, the technology nearly completely repaired wounds in just 12 days.

When the skin is cut or torn, the body’s natural “construction crew” kicks in to fix it back up — clearing out any bacterial invaders, regrowing broken blood vessels and eventually forming a scar. Many techniques used to heal wounds can’t do much beyond helping the body do its job better. Bandages or stitches are used to prevent further bleeding, while antibiotics work to prevent complications from infections. But by adding members of the construction crew to a wound-healing treatment or bandage, it could actually accelerate the natural healing process. Specifically, white blood cells or the extracellular vesicles (EVs) secreted from them play important roles in promoting blood vessel formation and reducing inflammation during healing. So, Dan Li, Xianguang Ding and Lianhui Wang wanted to incorporate these EVs into a hydrogel-based wound healing ink that could be painted into cuts of any shape.

The team developed a system called PAINT, or “portable bioactive ink for tissue healing,” using EVs secreted from macrophages combined with sodium alginate. These components were combined in a 3D-printing pen, where they mixed at the pen’s tip and formed a sturdy gel at the site of injury within three minutes. The EVs promoted blood vessel formation and reduced inflammatory markers in human epithelial cells, shifting them into the “proliferative,” or growth, phase of healing. PAINT was also tested on injured mice, where it promoted collagen fiber formation. Mice treated with PAINT had almost healed completely from a large wound after 12 days, compared to mice that didn’t receive the treatment, who were not nearly as far along in the healing process at this time point. The researchers say that this work could help heal a wide variety of cuts quickly and easily, without the need for complex procedures.

The authors acknowledge funding from the Leading-Edge Technology Programme of Jiangsu Natural Science Foundation, the Natural Science Foundation, the Natural Science Foundation of Jiangsu Province, the CAS [Chinese Academy of Sciences] Key Laboratory of Nano-Bio Interface, the Key Laboratory of Nanodevices and Applications, and the Postgraduate Research & Practice Innovation Program of Jiangsu Province.

The American Chemical Society (ACS) is a nonprofit organization chartered by the U.S. Congress. ACS’ mission is to advance the broader chemistry enterprise and its practitioners for the benefit of Earth and all its people. The Society is a global leader in promoting excellence in science education and providing access to chemistry-related information and research through its multiple research solutions, peer-reviewed journals, scientific conferences, eBooks and weekly news periodical Chemical & Engineering News. ACS journals are among the most cited, most trusted and most read within the scientific literature; however, ACS itself does not conduct chemical research. As a leader in scientific information solutions, its CAS division partners with global innovators to accelerate breakthroughs by curating, connecting and analyzing the world’s scientific knowledge. ACS’ main offices are in Washington, D.C., and Columbus, Ohio.

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

Paintable Bioactive Extracellular Vesicle Ink for Wound Healing by Li Li, Zhiyu Wang, Kepeng Wang, Siyuan Fu, Dan Li, Mao Wang, Yi Cao, Houjuan Zhu, Ziyan Li, Lixing Weng, Zhiyang Li, Xianguang Ding, and Lianhui Wang. ACS Appl. Mater. Interfaces 2023, 15, 21, 25427–25436 DOI: https://doi.org/10.1021/acsami.3c03630 Publication Date:May 19, 2023 Copyright © 2023 American Chemical Society

This paper is behind a paywall.

Exceeding the sensitivity of skin with a graphene elastomer

A Jan. 14, 2016 news item on Nanowerk announces the latest in ‘sensitive’ skin,

A new sponge-like material, discovered by Monash [Monash University in Australia] researchers, could have diverse and valuable real-life applications. The new elastomer could be used to create soft, tactile robots to help care for elderly people, perform remote surgical procedures or build highly sensitive prosthetic hands.

Graphene-based cellular elastomer, or G-elastomer, is highly sensitive to pressure and vibrations. Unlike other viscoelastic substances such as polyurethane foam or rubber, G-elastomer bounces back extremely quickly under pressure, despite its exceptionally soft nature. This unique, dynamic response has never been found in existing soft materials, and has excited and intrigued researchers Professor Dan Li and Dr Ling Qiu from the Monash Centre for Atomically Thin Materials (MCATM).

A Jan. 14, 2016 Monash University media release, which originated the news item, offers some insights from the researchers,

According to Dr Qiu, “This graphene elastomer is a flexible, ultra-light material which can detect pressures and vibrations across a broad bandwidth of frequencies. It far exceeds the response range of our skin, and it also has a very fast response time, much faster than conventional polymer elastomer.

“Although we often take it for granted, the pressure sensors in our skin allow us to do things like hold a cup without dropping it, crushing it, or spilling the contents. The sensitivity and response time of G-elastomer could allow a prosthetic hand or a robot to be even more dexterous than a human, while the flexibility could allow us to create next generation flexible electronic devices,” he said.

Professor Li, a director of MCATM, said, ‘Although we are still in the early stages of discovering graphene’s potential, this research is an excellent breakthrough. What we do know is that graphene could have a huge impact on Australia’s economy, both from a resources and innovation perspective, and we’re aiming to be at the forefront of that research and development.’

Dr Qiu’s research has been published in the latest edition of the prestigious journal Advanced Materials and is protected by a suite of patents.

Are they trying to protect the work from competition or wholesale theft of their work?

After all, the idea behind patents and copyrights was to encourage innovation and competition by ensuring that inventors and creators would benefit from their work. An example that comes to mind is the Xerox company which for many years had a monopoly on photocopy machines by virtue of their patent. Once the patent ran out (patents and copyrights were originally intended to be in place for finite time periods) and Xerox had made much, much money, competitors were free to create and market their own photocopy machines, which they did quite promptly. Since those days, companies have worked to extend patent and copyright time periods in efforts to stifle competition.

Getting back to Monash, I do hope the researchers are able to benefit from their work and wish them well. I also hope that they enjoy plenty of healthy competition spurring them onto greater innovation.

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

Ultrafast Dynamic Piezoresistive Response of Graphene-Based Cellular Elastomers by Ling Qiu, M. Bulut Coskun, Yue Tang, Jefferson Z. Liu, Tuncay Alan, Jie Ding, Van-Tan Truong, and Dan Li. Advanced Materials Volume 28, Issue 1 January 6, 2016Pages 194–200 DOI: 10.1002/adma.201503957 First published: 2 November 2015

This paper appears to be open access.