- The smart bandage can monitor the conditions of chronic wounds and deliver appropriate drugs.
- It has pH, temperature and oxygen sensors fabricated on parchment paper.
- All components are selected to keep its cost low.
Chronic non-healing wounds, like bed stones and diabetic foot, affect more than 6.5 million Americans every year. According to a research, it costs more than $25 billion to treat such wounds on an annual basis, and it’s increasing every year due to extending levels of diabetes and obesity in the aging population.
Existing treatments are generic, labor-intensive and quite expensive. Most often, they rely on typical cleaning, oxygen therapy, debridement (removal of damaged tissues) or systemic administration of antibiotics. Dressings available in hospitals and clinics — hydrocolloids, foams, hydrogels, alginate, and more — are not much effective.
Therefore, researchers at Tufts University have built a smart bandage to regularly monitor the condition of chronic wounds and deliver suitable drugs to increase the chances of healing. The prototype aims to transform the conventional, passive bandaging treatment into an efficient paradigm for addressing tough medical challenges.
Components of Smart Bandage
To aid natural healing process, the team developed the bandage with heating elements and thermo-responsive drug carriers, which can transfer suitable drugs in response to embedded temperature and pH sensors that monitor infection and inflammation.
A smart bandage with a microprocessor (left) and wound covering module (right) | Credit: Mike Silver/Tufts University
In contrast to conventional bandages, the smart bandage integrates sensors (oxygen, pH, inflammatory mediators), drug delivery (antibiotics, oxygen, stem cells), and electronic intelligence to significantly improve the healing process by monitoring individual responses and allowing suitable alterations to therapy. This is all done with limited intervention from the caregiver or patient.
How It Works?
One of the crucial parameters for tracking the progress of a chronic wound is pH level. Usual healing wounds have a pH value between 5.5 and 6.5, but for non-healing wounds, the value goes above 6.5. Another key parameter is temperature, which provides the inflammation level near the wound.
The smart bandage has nanoscale silver (used as antiseptic), pH, temperature and oxygen sensors fabricated on parchment (hydrophobic) paper. The oxygen delivery module relies on catalytic conversion of hydrogen peroxide over manganese dioxide nanoparticle deposited areas.
Oxygen generation and sensing patch | Courtesy of researchers
The hydrophobic paper is biocompatible and suitable for wound dressing. They can prevent hydrogen peroxide from touching the infected area and enable oxygen to diffuse to the wound bed.
All components of the smart bandage are selected to keep its cost low. Also, they have made all components disposable, except microprocessor, which can be reused.
Testing and Applications
This type of smart bandages have a variety of possibilities: it can be embedded with other sensing modules, drugs, and growth factors for treating different conditions in response to multiple healing markers.
The prototype has been successfully tested in vitro conditions (controlled environment outside of a living organism). The team is now conducting clinical studies in vivo conditions (living organisms) to determine its advantages over conventional bandages.
They might face following challenges while doing this:
- Printing necessary heterogeneous materials onto parchment paper under repeated bending cycles.
- Integration of flexible micro-fluid delivery channels.
- Appropriate encapsulation of electrical modules.