A Sensor Gauze With Multi-Channel Moisture and pH Monitoring for Chronic Wound Care

Chronic wounds (CWs) usually happen in diabetic foot ulcers, venous leg ulcers, and pressure ulcers. When wounds fail to achieve sufficient healing within four weeks, it indicates that bacteria in the wounds are promoting chronicity through relapse infections. Therefore, how to observe changes in a wound after it is covered with gauze to avoid the formation of CWs is important for clinical care. Previous studies showed that wound pH value distribution can be used as an important basis for infection and healing assessment. This paper proposed the design of sensor gauze with multi-channel moisture and pH monitoring for CWs. The moisture sensing analysis of different areas could be used to determine the distribution of the corresponding wound tissue fluid, as well as automatically carry out multi-area pH value measurements and wound analysis. The analysis results were graphically displayed on a monitoring device. The results indicated that the proposed design could measure pH values with high sensitivity (0.01 pH/mV) in the range of 3 to 10. Statistical correlation analysis revealed a strong correlation (R
²
= 0.97) between the standard meter and each pH sensing point. In the experimental correlation between the proposed device and the moisture device, the results show that there was a high correlation (R
²
= 0.97). The response time of the whole wound scan with four channels was within one second. This design has the potential to provide assistance for related clinical care applications.