Smart bandage with wireless connectivity for optical monitoring of pH

Wound care technologies need to adapt in order to cope with the growing socio-economic burden of chronic wounds. Non-invasive analytical systems which monitor important wound status biomarkers such as pH of wound fluid, are needed. In this work, a wireless smart bandage for optical determination of pH, as an indicator of wound status, is demonstrated and characterised. The bandage is constructed by immobilising cellulose particles, covalently modified with a pH indicator dye, within a biocompatible hydrogel. Thin layers of the pH sensitive hydrogel are cast onto a conventional dressing and interfaced to a wireless platform via a miniaturised optoelectronic probe. The smart bandage can detect pH changes in the physiologically relevant range with high accuracy and precision, and communicate this information with an external readout unit using radio-frequency identification (RFID). The new system could provide insight into temporal changes in wound status in a convenient and non-invasive manner, and prompt an appropriate response from a healthcare provider.