This Small Business Innovation Research (SBIR) Phase II project aims to develop and market the trademarked Dx-1 pH Measurement System. This medical device integrates the breath pH sensor studied in the Phase I research with an ambulatory, telemetry based data recorder, and data analysis software to provide a non-invasive pH diagnostic tool required by physicians. This pH sensor actively condenses a moisture film on the sensor surface, creating a conduction path across its sensing electrodes. During Phase II, the company plans to complete all technical and regulatory activities in order to gain FDA clearance for product introduction. The commercial application of this project is in the area of medical devices. The proposed sensor technology will offer a new tool for clinicians to more effectively diagnose and treat respiratory diseases, particularly for children and infants who cannot readily undergo alternative diagnostic procedures.