A disposable breath sensing tube with on-tube single-nanowire sensor array for on-site detection of exhaled breath biomarkers

Abstract

This paper presents a novel disposable breath-sensing tube with an on-tube single-nanowire (NW) sensor array for noninvasive, simple, and on-site detection of exhaled breath biomarkers. Although various noninvasive detection methods for lung cancer biomarkers in breath samples exist, they are unsuitable for self-diagnostics and immediate detection because they entail complicated handling procedures and are time intensive. In this study, we simulated, fabricated, and characterized disposable nanosensors by using single TiO and Ag NWs in flexible plastic tubes. The proposed sensors simultaneously detect 2-propyl-1-pentanol (2-PP) lung cancer biomarkers and changes in the humidity, flow rate, and temperature of the flowing gas. The optimal dimension of the tubes was determined and verified through dynamic simulations and experiments. The current tube design decreases sensing variation and moisture interference by 43.28% and 78.77%, respectively, compared with previous designs. In the future, the proposed breath sensor, which has a response time of less than 10 s, can be used in a tube for simple and quick screening of lung cancer patients with the 2-PP concentration exceeding 100 ppb. The developed breath-sensing platform can be applied in noninvasive on-site disease screening.

Flexible Antibacterial Respiratory Monitoring Sensor Based on Controllable Au-Modified Surface of Highly {001} Preferred Anatase Titanium Dioxide Thin Film

“…The insensitivity to other environmental variables fully showcased the advantage of the mechanical-based sensing mechanism of ARMS, which is capable of providing accurate and reliable respiratory parameters for practical applications. Compared with other TiO 2 -based respiratory sensors as listed in Table , the ARMS showed much better respiratory sensing performance, in terms of fast response and recovery time and low operate temperature. ,,,− ,− Combining the low-cost fabrication, inherent flexibility, and antibacterial performance, the proposed respiratory sensor has great potential for personal health monitoring and epidemic prevention.…”

“…However, the wide band gap of TiO 2 limits its application, requiring the assistance of the UV region or high temperature to excite electrons from the valence band to the conduction band, thereby achieving catalytic action. − To meet the needs of daily use, great efforts have been made to improve the photocatalytic performance of TiO 2 in the visible light region at room temperature (25 °C), including the individual or combined utilization of dye sensitization, loading with noble metals, doping with transition metals, and exploiting nonstoichiometric titanium oxides and their heterostructures. − Of note, even though nonstoichiometric titanium oxides enable an extended operational wavelength beyond UV limits, they are still severely affected by humidity at room temperature, necessitating an additional heating unit to ensure measurement accuracy . The surface plasmon resonance (SPR) effect induced by plasmonic metals (mostly noble metals) has been demonstrated as an effective approach to extend the photocatalytic working range from UV to the visible light region. ,, The resonance of plasmonic metal nanoparticles determined by their shape and size leads to strong light absorption at a certain wavelength, resulting in a highly excited state and the generation of a locally enhanced electric field. , The localized enhanced electric field resulting from SPR of Au reduces the threshold energy to excite the valence band electrons of TiO 2 , thereby improving the activity of TiO 2 in the visible light range.…”

Wearable and implantable bioelectronics as eco‐friendly and patient‐friendly integrated nanoarchitectonics for next‐generation smart healthcare technology

“…In addition, the selectivity of bioelectronics as a sensor for disease biomarkers can be improved by using various types of bioreceptors, such as antibodies, aptamers, and peptides/proteins, improving the potential for bioelectronic systems to be applied to healthcare 132–139 . Last, the mixture of gases and vapors of human breath has potential as a completely noninvasive and safe target for health diagnosis and monitoring 140,141 . By detecting volatile biomarkers present in the breath, follow‐up for a patient's health can be assessed 9 …”

“…[132][133][134][135][136][137][138][139] Last, the mixture of gases and vapors of human breath has potential as a completely noninvasive and safe target for health diagnosis and monitoring. 140,141 By detecting volatile biomarkers present in the breath, follow-up for a patient's health can be assessed. 9 2.1.4 | Bioelectronics in healthcare: Stimulation, actuation, and therapeutics Bioelectronic systems, especially implantable bioelectronics, have extensive applications in many diseases that are caused by dormant or aberrant neural networks.…”

Performance of Flexible Chemoresistive Gas Sensors after Having Undergone Automated Bending Tests

“…Metal oxide nanowires are ideal for gas sensor fabrication owing to their high surface-to-volume ratio, their superior stability, the possibility of reaching high integration densities, and their easy integration into microelectronic devices [9]. Recently, nanowires have been used to develop a variety of gas sensors employing flexible substrates [10,11,12,13]. Despite the remarkable results achieved, their flexibility and response under cyclic bending have been barely studied.…”