Penso multiresponsivo para o controlo e tratamento de feridas crónicas

How can a multiresponsive wound dressing be developed to act as both a diagnostic and therapeutic device? MuSSHeal project will develop intelligent wound dressings able to monitor the wound healing process, through the colour change as a result of pH changes at wound bed. Such a distinguishable characteristic will be achieved through the integration of a pH sensor (anthocyanins obtained from juice industries) into wound dressings. Also, the incorporation of pH-responsive nanoparticles will allow to control skin infections through the controlled drug release of bioactive compounds with antimicrobial/anti-inflammatory activity after increase of wound pH value in case of infection (as illustrated in figure available in annex I). Moreover, the dressing based on piezoelectric and pyroelectric biodegradable polymer with photothermal Au nanoparticles, will allow the generation of electroactive stimulation to promote wound healing. Aim 1: Anthocyanins obtained from berries pomace act as colorimetric pH sensors. The pomace obtained from the juice industries (working with mulberry and blueberry) will be used as the source of anthocyanins. Different extraction protocols will be tested and optimized to obtain pure and stable anthocyanins exhibit a colorimetric behaviour in response to pH alterations. Such optimization steps will ensure the obtainment that the optimal and stable natural pH sensor is obtained to be incorporated into the wound dressings, and that a colour/pH scale is established. Aim 2: The pH-responsive nanoparticles allow the controlled release of antimicrobial and anti-inflammatory compounds. The CAP-based nanoparticles incorporating antimicrobial and anti-inflammatory compounds will be produced by adopting different methodologies. The morphological properties, stability and biological properties of nanoparticles will be evaluated. In addition, the antimicrobial/anti-inflammatory compounds-controlled release profile will be characterized at different physiological pH and antibacterial and antibiofilm activity will also be assessed. Aim 3: Intelligent and multiresponsive wound dressings are obtained. 3D printed hydrogels will be interpenetrated with the electrospun fibres composed of mechanically and light stimulated electroactive materials based on piezo- and pyroelectric biodegradable polymers. The anthocyanins and pH-responsive nanoparticles will be incorporated into wound dressings. For their composition, the polymers (e.g. PHBV and PLLA) will be used and eventually combined with gels based on natural polymers (e.g. gelatin, sericin, or collagen) where the active substances will be placed for controlled release. By exploring the potential of different methodologies, distinct multifunctional dressings will be obtained to be evaluated in further steps. Aim 4: Intelligent and multiresponsive wound dressings act as a diagnostic and therapeutic medical device. The multifunctional wound dressings monitor the pH changes during the wound healing process through colour change, and simultaneously avoid the occurrence of skin infections. In addition, their piezoelectric and pyroelectric properties will promote cell proliferation and migration, and consequently acceleration of the wound healing process.