A Wearable Respiration Sensor for Real-Time Monitoring of Chronic Kidney Disease

Human respiration is accompanied with abundant physiological and pathological information, such as the change in ammonia (NH₃) content, which is related to chronic kidney disease (CKD); hence, monitoring the breathing behavior helps in health assessment and illness prediction. In this work, a wearable respiration sensor based on CeO₂@polyaniline (CeO₂@PANI) nanocomposites that underwent a hydrogen plasma treatment is developed. The results unambiguously show that the response of the corresponding nanocomposites is significantly enhanced from 165 to 670% to 100 ppm NH₃ compared to the counterpart that did not undergo hydrogen plasma treatment and even reaches 24% to 50 ppb NH₃, suggesting its fascinating capability of detecting the trace level of NH₃ in human breathing. The superior response for NH₃ is ascribed to the stable oxygen vacancies produced by the hydrogen plasma treatment. Furthermore, the clinical tests for patients with uremia suggest that the as-designed sensor has potential applications in clinical monitoring for CKD. Herein, this work offers a new strategy to obtain respiration sensors with high performance and provides a feasible approach for health evaluation and disease monitoring of patients with CKD.