It's certainly ironic that in order to see how a wound is healing, the dressing has to be removed, potentially setting back the healing process. A clever new bandage, however, continuously shows how the wound is faring – without needing a power source.
Developed by a team of scientists at the National University of Singapore, the experimental dressing is known as the PETAL (Paper-like Battery-free In situ AI-enabled Multiplexed) sensor patch. Along with being a bit of a forced acronym, the bandage's name also refers to the fact that it looks (sort of) like a pinwheel flower.
The multilayered device consists of a bottom layer of medical tape that adheres to the skin surrounding the wound, a middle "fluidic panel" layer of wax paper incorporating microfluidic channels arranged in a five-petalled flower pattern, and a breathable top layer of transparent silicone.
When the PETAL is applied to a wound, fluid from that wound is passively drawn through an opening in the fluidic panel and distributed into the five channels which form the flower's petals.
Once the fluid reaches a chemical contained in a reservoir at the end of each channel (a different chemical in each reservoir), that chemical changes color in response to one of five "wound indicators" – temperature, pH, uric acid levels, moisture, and concentrations of a metabolic waste product known as trimethylamine.
By taking a smartphone photo of the PETAL, then using an AI-based app to analyze the colors of the reservoirs in that photo, it's possible to assess the current state of the wound without removing the dressing. In tests performed on rats, the technology proved to be 97% accurate at differentiating between healing and non-healing chronic and burn wounds.
"We designed the paper-like PETAL sensor patch to be thin, flexible and biocompatible, allowing it to be easily and safely integrated with wound dressing for the detection of biomarkers," said the principal scientist, Dr. Su Xiaodi. "We can thus potentially use this convenient sensor patch for prompt, low-cost wound care management at hospitals or even in non-specialist healthcare settings such as homes."
A paper on the research was recently published in the journal Science Advances.
Source: National University of Singapore
