Tag Archives: Vi Khanh Truong

Textiles fight back bacteria with electronics

These textiles according to an April 24, 2023 news item on SpaceDaily do a little more than fight off bacteria (as impressive as that is),

Scientists from around the world have developed a simple metallic coating treatment for clothing or wearable textiles which can repair itself, repel dangerous bacteria from the wearer and even monitor a person’s electrocardiogram (ECG) heart signals.

Researchers from North Carolina State University [US], Flinders University [Australia] and South Korea [Sungkyunkwan University (SKKU] say the conductive circuits created by liquid metal (LM) particles can transform wearable electronics and open doors for further development of human-machine interfaces, including soft robotics and health monitoring systems.

An April 25, 2023 Flinders University press release (also on EurekAlert but published April 26, 2023), which originated the news item, provides more technical details about the conductive, self-healing textiles, Note: Links have been removed,

The ‘breathable’ electronic textiles have special connectivity powers to ‘autonomously heal’ itself even when cut, says the US team led by international expert in the field, Professor Michael Dickey.  

When the coated textiles are pressed with significant force, the particles merge into a conductive path, which enables the creation of circuits that can maintain conductivity when stretched, researchers say.   

“The conductive patterns autonomously heal when cut by forming new conductive paths along the edge of the cut, providing a self-healing feature which makes these textiles useful as circuit interconnects, Joule heaters and flexible electrodes to measure ECG signals,” says Flinders University medical biotechnology researcher Dr Khanh Truong, senior co-author in a new article in Advanced Materials Technologies. 

The technique involves dip-coating fabric into a suspension of LM particles at room temperature.  

“Evenly coated textiles remain electrically insulating due to the native oxide that forms on the LM particles. However, the insulating effect can be removed by compressing the textile to rupture the oxide and thereby allow the particles to percolate.  

“This enables the creation of conductive circuits by compressing the textile with a patterned mold. The electrical conductivity of the circuits increases by coating more particles on the textile.”  

As well the LM-coated textiles offer effective antimicrobial protection against Pseudomonas aeruginosa and Staphylococcus aureus.  

This germ repellent ability not only gives the treated fabric protective qualities but prevents the porous material from becoming contaminated if worn for and extended time, or put in contact with other people.    

The particles of gallium-based liquid metals have low melting point, metallic electrical conductivity, high thermal conductivity, effectively zero vapor pressure, low toxicity and antimicrobial properties.  

LMs have both fluidic and metallic properties so show great promise in applications such as microfluidics, soft composites, sensors, thermal switches and microelectronics.  

One of the advantages of LM is that it can be deposited and patterned at room temperature onto surfaces in unconventional ways that are not possible with solid metals. 

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

Liquid Metal Coated Textiles with Autonomous Electrical Healing and Antibacterial Properties (2023) by Jiayi Yang, Praneshnandan Nithyanandam, Shreyas Kanetkar, Ki Yoon Kwon, Jinwoo Ma, Sooik Im, Ji-Hyun Oh, Mohammad Shamsi, Mike Wilkins, Michael Daniele Tae-il Kim, Huu Ngoc Nguyen, Vi Khanh Truong and Michael D Dickey. Advanced Materials Technologies Online Version of Record before inclusion in an issue 2202183 DOI: 10.1002/admt.202202183 First published: 02 April 2023 [2nd DOI:] https://doi.org/10.1002/admt.202202183 

This paper is open access.

Glowing suture material could reduce infection and simplify post op monitoring

Reassuringly, you won’t be waking up in the hospital to see your sutures glowing in the dark. On that note, here’s more about the innovation in a February 1, 2023 news item on ScienceDaily,

A new antimicrobial suture material that glows in medical imaging could provide a promising alternative for mesh implants and internal stitches.

Surgical site infections are one of the most common medical infections, occurring in 2 to 4% of patients post-surgery. For some procedures, such as vaginal mesh implants to treat prolapse, infection rates can be higher.

Study lead author and Vice Chancellor’s Senior Research Fellow [RMIT University, Australia], Dr Shadi Houshyar, said their suture was being developed in partnership with clinicians specifically for this type of procedure.

Caption: The filament visible in chicken samples, as seen under CT scan. Credit: RMIT University

A February 1, 2023 RMIT University press release (also on EurekAlert but published January 31, 2023), which originated the news item, provides more context and technical detail about the research,

“Our smart surgical sutures can play an important role in preventing infection and monitoring patient recovery and the proof-of-concept material we’ve developed has several important properties that make it an exciting candidate for this,” said Houshyar, from the School of Engineering at RMIT University, Australia.

Lab tests on the surgical filament, published in OpenNano, showed it was easily visible in CT scans when threaded through samples of chicken meat, even after three weeks. It also showed strong antimicrobial properties, killing 99% of highly drug-resistant bacteria after six hours at body temperature.

Houshyar said the team was not aware of any commercially available suture products that combined these properties.

How they did it

The multidisciplinary team led by RMIT – included nano-engineering, biomedical and textile experts working in partnership with a practicing surgeon – used the university’s cutting-edge textile manufacturing facility to develop their proof-of-concept material.

The suture’s properties come from the combination of iodine and tiny nanoparticles, called carbon dots, throughout the material.

Carbon dots are inherently fluorescent, due to their particular wavelength, but they can also be tuned to various levels of luminosity that easily stand out from surrounding tissue in medical imaging.

Attaching iodine to these carbon dots, meanwhile, provides them with their strong antimicrobial properties and greater X-ray visibility.

Houshyar said carbon nano dots were safe, cheap and easy to produce in the lab from natural ingredients.

“They can be tailored to create biodegradable stitches or a permanent suture, or even to be adhesive on one side only, where required,” she said.

“This project opens up a lot of practical solutions for surgeons, which has been our aim from the start and the reason we have involved clinicians in the study.”

Clinical possibilities

Consultant colorectal surgeon and Professor of Surgery at the University of Melbourne, Justin Yeung, was involved in the study. He said it addressed a real challengefaced by surgeons in trying to identify the precise anatomical location of internal meshes on CT scans.

“This mesh will enable us to help with improved identification of the causes of symptoms, reduce the incidence of mesh infections and will help with precise preoperative planning, if there is a need to surgically remove this mesh,” he said.

“It has the potential to improve surgery outcomes and improve quality of life for a huge proportion of women, if used as vaginal mesh for example, by reducing the need for infected mesh removal.”

“It may also significantly reduce surgery duration and increase surgical accuracy in general through the ability to visualise mesh location accurately on preoperative imaging.” 

Next steps

Study co-author from RMIT’s School of Health and Biomedical Sciences, Professor Elisa Hill-Yardin, said the next steps were pre-clinical trials.

“While this research is at an early stage, we believe we are onto something very promising that could help a lot of people and are really keen to speak with industry partners who are interested in working with us to take it further,” she said.

“We see potential especially in vaginal mesh implants and similar procedures.”

The research team used Australia’s leading university-based textile manufacturing facilities at RMIT’s Centre for Materials Innovation and Future Fashion to produce the proof-of-concept material. They will soon be producing larger suture samples to use in pre-clinical trials, which they have just received seed funding for from RMIT.

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

Smart suture with iodine contrasting nanoparticles for computed tomography by Shadi Houshyar, Hong Yin, Leon Pope, Rumbidzai Zizhou, Chaitali Dekiwadia, Elisa L. Hill-Yardin, Justin MC Yeung, Sabu John, Kate Fox, Nhiem Tran, Ivan Cole, Aaron Elbourne, Vi Khanh Truong, and Adam Truskewycz. OpenNano Volume 9, January 2023, 100120 DOI: https://doi.org/10.1016/j.onano.2022.100120

This paper is open access.