A Novel Modular eNose System Based on Commercial MOX Sensors to Detect Low Concentrations of VOCs for Breath Gas Analysis

In this work, a new generation of eNose systems particularly suited for exhaled breath gas analysis is presented. The developed analyzer system comprises a compact modular, low volume, temperature controlled sensing chamber explicitly tested for the detection of acetone, isoprene, pentane and isopropanol. The eNose system sensing chamber consists of three compartments, each of which can contain 8 analog Metal Oxide (MOX) sensors or 10 digital MOX sensors. Additional sensors within the digital compartment allow for pressure, humidity and temperature measurements. The presented eNose system contains a sensor array with up to 30 physical sensors and provides the ability to discriminate between low VOC concentrations under dry and humid conditions. The MOX sensor signals were analyzed by pattern recognition methods.

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Metal Oxide Nanorods-Based Sensor Array for Selective Detection of Biomarker Gases

Sensors ◽

10.3390/s21051922 ◽

2021 ◽

Vol 21 (5) ◽

pp. 1922

Author(s):

Gwang Su Kim ◽

Yumin Park ◽

Joonchul Shin ◽

Young Geun Song ◽

Chong-Yun Kang

Keyword(s):

Real Time ◽

Sensor Array ◽

High Sensitivity ◽

Gas Analysis ◽

Diagnostic Methods ◽

Real Time Monitoring ◽

Non Invasive ◽

Sensitivity And Selectivity ◽

Breath Gas Analysis ◽

Angle Method

The breath gas analysis through gas phase chemical analysis draws attention in terms of non-invasive and real time monitoring. The array-type sensors are one of the diagnostic methods with high sensitivity and selectivity towards the target gases. Herein, we presented a 2 × 4 sensor array with a micro-heater and ceramic chip. The device is designed in a small size for portability, including the internal eight-channel sensor array. In2O3 NRs and WO3 NRs manufactured through the E-beam evaporator’s glancing angle method were used as sensing materials. Pt, Pd, and Au metal catalysts were decorated for each channel to enhance functionality. The sensor array was measured for the exhaled gas biomarkers CH3COCH3, NO2, and H2S to confirm the respiratory diagnostic performance. Through this operation, the theoretical detection limit was calculated as 1.48 ppb for CH3COCH3, 1.9 ppt for NO2, and 2.47 ppb for H2S. This excellent detection performance indicates that our sensor array detected the CH3COCH3, NO2, and H2S as biomarkers, applying to the breath gas analysis. Our results showed the high potential of the gas sensor array as a non-invasive diagnostic tool that enables real-time monitoring.

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A Novel Modular System for Breath Analysis Using Temperature Modulated MOX Sensors

Proceedings ◽

10.3390/proceedings2019014049 ◽

2019 ◽

Vol 14 (1) ◽

pp. 49 ◽

Cited By ~ 3

Author(s):

Carsten Jaeschke ◽

Oriol Gonzalez ◽

Marta Padilla ◽

Kaylen Richardson ◽

Johannes Glöckler ◽

...

Keyword(s):

Gas Sensing ◽

Breath Analysis ◽

The Other ◽

Modular System ◽

Sensing Systems ◽

Low Concentrations ◽

Temperature Controlled ◽

Low Volume ◽

New Generation ◽

Mox Sensors

In this work, a new generation of gas sensing systems specially designed for breath analysis is presented. The developed system comprises a compact modular, low volume, temperature-controlled sensing chamber with three compartments that can host different sensor types. In the presented system, one compartment contains an array of 8 analog MOX sensors and the other two 10 digital MOX sensors each. Here, we test the system for the detection of low concentrations of several compounds.

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Drift Compensation of the Electronic Nose in the Development of Instruments for Out-of-Laboratory Analysis

Chemistry Proceedings ◽

10.3390/csac2021-10464 ◽

2022 ◽

Vol 5 (1) ◽

pp. 68

Author(s):

Anastasiia Shuba ◽

Tatiana Kuchmenko ◽

Dariya Menzhulina

Keyword(s):

Electronic Nose ◽

Sensor Array ◽

Exhaled Breath Condensate ◽

Laboratory Analysis ◽

Exhaled Breath ◽

Statistical Process ◽

Sensor Signals ◽

Internal Standardization ◽

The Stability

A technique was developed to evaluate and compensate for the drift of eight mass-sensitive sensors in an open detection cell in order to estimate the influence of external factors (temperature, changes in the chemical composition of the background) on the out-of-laboratory analysis of biosamples. The daily internal standardization of the system is an effective way to compensate for the sensor signal drift when the sorption properties of sensitive coatings change during their long-term, intensive operation. In this study, distilled water was proposed as a standard for water matrix-based biosamples (blood, exhaled breath condensate, urine, etc.). Further, internal standardization was based on daily calculation of the specific sensor signals by dividing the sensor signals for the biosample according to the corresponding averaged values obtained from three to five standard measurements. The stability of the sensor array operation was estimated using the theory of statistical process control (exponentially weighted moving average control charts) based on the specific signal of the sensor array. The control limits for the statistical quantity of the central tendency for each sensor and the whole array, as well as the variations of the sensor signals, were determined. The average times required for signal and run lengths, for the purpose of statistically substantiated monitoring of the electronic nose’s stability, were calculated. Based on an analysis of the tendency and variations in sensor signals during 3 months of operation, a technique was formulated to control the stability of the sensor array for the out-of-laboratory analysis of the biosamples. This approach was successfully verified by classifying the results of the analysis of the blood and water samples obtained for this period. The proposed technique can be introduced into the software algorithm of the electronic nose, which will improve decision-making during the long-term monitoring of health conditions in humans and animals.

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Real-time breath gas analysis for pharmacokinetics: monitoring exhaled breath by on-line proton-transfer-reaction mass spectrometry after ingestion of eucalyptol-containing capsules

Journal of Breath Research ◽

10.1088/1752-7155/4/2/026006 ◽

2010 ◽

Vol 4 (2) ◽

pp. 026006 ◽

Cited By ~ 58

Author(s):

J Beauchamp ◽

F Kirsch ◽

A Buettner

Keyword(s):

Mass Spectrometry ◽

Proton Transfer ◽

Real Time ◽

Transfer Reaction ◽

Proton Transfer Reaction ◽

Gas Analysis ◽

Reaction Mass ◽

Exhaled Breath ◽

On Line ◽

Breath Gas Analysis

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ZIF Nanocrystal-Based SAW Electronic Nose to Detect Diabetes in Human Breath

10.20944/preprints201811.0210.v1 ◽

2018 ◽

Author(s):

Fabio A. Bahos ◽

Arianee Sainz-Vidal ◽

Celia Sánchez-Pérez ◽

José M. Saniger ◽

Isabel Gràcia ◽

...

Keyword(s):

Sensor Array ◽

Signal Recovery ◽

Exhaled Breath ◽

Human Breath ◽

Saw Sensor ◽

Non Invasive ◽

Disease Markers ◽

Low Concentrations ◽

Short Time ◽

Early Diagnosis Of Diabetes

In the present work a novel, portable and innovative eNose composed of a surface acoustic wave (SAW) sensor array based ZIF-8, and ZIF-67 nanocrystals (pure and combined with gold nanoparticles) as sensitive layers has been tested as a non-invasive system to detect and differentiate disease markers, such as acetone, ethanol and ammonia, related with early diagnosis of diabetes mellitus through exhaled breath. The sensors have been prepared by spin coating, achieving continuous and homogenous sensitive layers. Low concentrations (5 ppm, 10 ppm and 25ppm) of the marker analytes were measured, obtaining high sensitivities, good reproducibility, short time response and fast signal recovery.

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