Wearable Dual-Signal NH₃ Sensor with High Sensitivity for Non-invasive Diagnosis of Chronic Kidney Disease

Abstract

NH 3 gas in human exhaled breath contains abundant physiological information related to human health, especially chronic kidney disease (CKD). Unfortunately, up to now, most wearable NH 3 sensors show inevitable defects (low sensitivity, easy to be interfered by the environment, etc.), which may lead to misdiagnosis of CKD. To solve the above dilemma, a nanoporous, heterogeneous, and dual-signal (optical and electrical) wearable NH 3 sensor mask is developed successfully. More specifically, a polyacrylonitrile/ bromocresol green (PAN/BCG) nanofiber film as a visual NH 3 sensor and a polyacrylonitrile/polyaniline/reduced graphene oxide (PAN/PANI/rGO) nanofiber film as a resistive NH 3 sensor are constructed. Due to the high specific surface area and abundant NH 3 binding sites of these two nanofiber films, they exhibit good NH 3 sensing performance. However, although the visual NH 3 sensor (PAN/BCG nanofiber film) is simple without the need of any detecting facilities and quite stable when temperature and humidity change, it shows poor sensitivity and resolution. In comparison, the resistive NH 3 sensor (PAN/PANI/rGO nanofiber film) is of high sensitivity, fast response, and good resolution, but its electrical signal is easily interfered by the external environment (such as humidity, temperature, etc.). Considering that the sensing principles between a visual NH 3 sensor and resistive NH 3 sensor are significantly different, a wearable dual-signal NH 3 sensor containing both a visual NH 3 sensor and resistive NH 3 sensor is further explored. Our data prove that the two sensing signals in this dual-signal NH 3 sensor mask can not only work well without interference with each other but also complement each other to improve the sensing accuracy, indicating its potential application in non-invasive diagnosis of CKD.

Porous Conductive Textiles for Wearable Electronics

“…Hence, electrospun nanofibers with ultrafine diameters become a promising substrate to fabricate gas sensors . For example, a PAN/PANI/rGO composite nanofiber, prepared by coating PAN nanofibers with rGO and PANI, showed high sensitivity (0–50 ppm) and fast response (70 s, 90% response) toward NH 3 gas . By integrating this NH 3 sensor on a mask, it is capable of distinguishing healthy people and patients with chronic kidney disease (CKD).…”

Enhanced Acetone-Sensing Properties of Pt-Decorated In2O3 Hollow Microspheres Derived from Pt-Embedded Template

“…However, the application of these methods in routine inspection and monitoring is greatly limited by the large equipment, high cost, and complex principle. 6 Metal oxide semiconductors (MOSs) are frequently utilized in gas detection. MOS research has advanced significantly in recent decades due to its high sensitivity, low cost, and simplicity of integration.…”

“…At present, optical spectroscopy methods and gas chromatography/mass spectrometry (GC–MS) have been considered as the common means to analyze exhaled breath. However, the application of these methods in routine inspection and monitoring is greatly limited by the large equipment, high cost, and complex principle …”

Machine Learning-Assisted Janus Colorimetric Face Mask for Breath Ammonia Analysis

“…20−23 Salivary urease in patients with CKD breaks down urea into ammonia, which is then expelled through the respiratory tract. 24 H. pylori can promote the conversion of urea into ammonia and bicarbonate in the body. 20 Therefore, a portable method for breath ammonia sensing is important for protecting human health.…”

“…If a person has chronic kidney disease (CKD) or is infected with Helicobacter pylori (H. pylori), the level of breath ammonia will be higher than 2 ppm, while a healthy individual’s breath ammonia is less than 2 ppm. − Salivary urease in patients with CKD breaks down urea into ammonia, which is then expelled through the respiratory tract H.…”