Ppb-level NH3 Sensing Utilizing MoS2 Nanoflowers Towards Developing Exhaled-Breath based Point-of-Care Diagnosis of Chronic Kidney Diseases

This study explores the potential of detecting renal failure and chronic kidney diseases (CKD) by analyzing elevated ammonia (NH 3 ) levels in exhaled breath, offering a non-invasive, point-of-care diagnostic approach. Healthy individuals exhibit NH 3 levels between 50 and 1500 ppb in exhaled breath, whereas those with renal dysfunction display concentrations from 1500 to 15000 ppb. The research develops a cost-effective, rapid-response NH 3 sensor using MoS 2 nanoflowers, demonstrating impressive performance with a response magnitude (RM) of around 40% at 100 ppm NH 3 and a response time of 92 seconds. It also achieves a limit of detection (LoD) at 100 ppb NH 3 , with an RM of approximately 5% and a response time of 37 seconds. Even in humid conditions (95% relative humidity), the sensor maintains its limit of detection (LoD), making it a valuable tool for early diagnosis. This work addresses the pressing need for renal disease detection and showcases the potential of Transition Metal Dichalcogenide (TMDC) materials for cost-effective, non-invasive NH 3 sensing.