Oxygen Sensor Research Articles

AI-Based Virtual Sensing of Gaseous Pollutant Emissions at the Tailpipe of a High-Performance Vehicle

<div>This scientific publication presents the application of artificial intelligence (AI) techniques as a virtual sensor for tailpipe emissions of CO, NOx, and HC in a high-performance vehicle. The study aims to address critical challenges faced in real industrial applications, including signal alignment and signal dynamics management. A comprehensive pre-processing pipeline is proposed to tackle these issues, and a light gradient-boosting machine (LightGBM) model is employed to estimate emissions during real driving cycles. The research compares two modeling approaches: one involving a unique “direct model” and another using a “two-stage model” which leverages distinct models for the engine and the aftertreatment. The findings suggest that the direct model strikes the best balance between simplicity and accuracy. Furthermore, the study investigates two sensor setups: a standard configuration and an optimized one, which incorporates an additional lambda probe in the exhaust line after the main catalyst. The results indicate a significant enhancement in performance for NOx and CO estimations with the introduction of the third lambda probe, while HC results remain relatively unchanged. Additionally, the AI model is tested on two different electronic control unit (ECU) software calibrations, yielding excellent results in both cases. This suggests that machine learning models are robust to control software variation and can be used to optimize software calibrations in a virtual environment, reducing the reliance on extensive experimental testing. Moreover, the AI model’s performance demonstrates compatibility with real-time implementation. In conclusion, this work establishes the viability and efficiency of AI techniques in accurately estimating tailpipe emissions from an engine in an industrial context. The study showcases the potential for AI to contribute to emission estimation and optimization processes, offering a promising pathway for an innovative industrial practice.</div>

Development of rapid hypoxia-detectable artificial oxygen carriers with a core–shell structure and erythrocyte mimetic shape

Oxygen probe molecules such as platinum(ii) octaethylporphine (PtOEP) have been successfully immobilized in the polymer shell of erythrocyte-mimetic perfluorocarbon artificial oxygen carriers as oxygen sensors.

High-Resolution Respirometry for Mitochondrial Function in Rodent Brain.

High-resolution mitochondrial respirometry is a modern technique that enables to measure mitochondrial respiration in various cell types. It contains chambers with oxygen sensors that measure oxygen concentration via polarography and calculate its consumption. The chamber contains plastic stoppers with injection ports that allow the injection of samples and different substrates, inhibitors, and uncoupler substances to measure mitochondrial respiration with high efficiency. These substances act on the mitochondrial electron transport chain (ETC) and help toassess the mitochondrial ATP production capacity and oxidative phosphorylation. The respirograph obtained with the help of software represents the oxygen consumption in each stage after adding different reagents.

The impact of zwitterionic surfactants on optode-based nanosensors via different fabrication approaches and sensing mechanisms.

In this work, we explored the impact of zwitterionic surfactants, sulfobetaine 16 (SB-16) and a PEG-phospholipid conjugate (DSPE-PEG), on nanosensor performance. We fabricated four sensors (for Na+, K+, Al3+, and O2) and examined how these surfactants influenced various aspects, including fabrication methods, sensing mechanisms, and the incorporation of nanomaterials. Our results highlighted SB-16's role in enhancing selectivity in ion-exchange sensors (Na+ and K+) while maintaining sensitivity akin to its PEG counterpart. The liquid-liquid extraction based sensors (Al3+) were unaffected by surfactant choice, while the O2 sensors that operate via collisional quenching exhibited reduced sensitivity with SB-16 when compared to its PEG-based counterpart. Additionally, the SB-16 sensors proved adaptable to different fabrication approaches (SESE - single emulsion solvent evaporation and FNP - flash nanoprecipitation), showcased good cell viability and maintained a functional lifetime of at least five days. Furthermore, via the use of quantum dots, we showed that it is possible to incorporate other nanomaterials into the sensing phase of SB-16 sensors. Future investigations could target enhancing the pH stability of zwitterionic surfactants to further advance their applicability in sensor technologies.

CO2-Based micro-respirometry for measuring bacterial load under aerobic and anaerobic conditions.

The bacterial load (BL), or total viable count, of aerobes can be measured using micro-respirometry, %O2-μR, in which the consumption of dissolved O2 is monitored with respect to incubation time, t. In %O2-μR the 'bioreactor' often comprises a canonical plastic tube with a small %O2 sensor; it is simple, fast and accurate and used in automated, commercial instruments for measuring BL. Here we show that it is also possible to measure BL using a new form of micro-respirometry, %CO2-μR, in which the production of CO2 in the growth medium is monitored. In %CO2-μR, the 'bioreactor' is the same as that used in %O2-μR, but with a small 3D printed, colour-based %CO2 indicator set in its base and its apparent absorbance, A', is measured at any t, as it is related to the %CO2 dissolved in the inoculated growth medium. Under aerobic conditions, different inoculations of the facultative anaerobe, E. coli, of different concentrations (101-108 colony forming units (CFU) per mL) are used to generate a series of A' vs. t profiles, and a straight-line calibration curve. Statistical comparative analysis of the results generated in the above %CO2-μR study, to those generated for the same system but using a commercial %O2-μR system, is used to demonstrate method equivalence. A study of the same system, under anaerobic conditions, using %CO2-μR, shows that %CO2-μR is suitable for measuring the BL of anaerobes. The potential of %CO2-μR for measuring the bacterial load of CO2-generating aerobes and anaerobes is discussed briefly.

Cost-Effective Monitoring of the Fuel Air Equivalence-Ratio with a Lambda Sensor and a Microcontroller in a Downdraft Biomass Gasifier

Cost-Effective Monitoring of the Fuel Air Equivalence-Ratio with a Lambda Sensor and a Microcontroller in a Downdraft Biomass Gasifier

Remembering Medical Ventilators and Masks in the Days of COVID-19: Patenting in the Last Decade in Respiratory Technologies

Health systems, which have been under great pressure with the COVID-19 outbreak, encountered problems in accessing some urgently needed medical resources. One of these resources has been the medical ventilators needed in acute respiratory distress syndrome developing with COVID-19. As a result of the calls made, many manufacturers have modified their facilities to produce medical ventilators and the problem has been solved to a great extent. While we focus on the urgent requirement for ventilators in these troubled days of COVID-19, we do not seem to be worth discussing their technical developments. How did the countries perform in the development of novel respiratory technologies in the pre-COVID period? While patents are seen as a measure of inventive activity, we attempt to draw a general picture of patents granted in the field of medical respiratory technologies. Our study examines 27 397 respiratory patents listed in the Derwent Innovations Index database at the last 50 years and focuses on the last decade for further evaluation. In addition to the analysis of patent numbers, we identified the core ventilation technologies of the last two decades with the topic modeling technique and compared them. We used the claims section of the patents collected. It is seen that focus of ventilation patents granted between 2001 and 2010 was on oxygen, flow generation, and pressure sensors while it shifted to the pipes, measurement methods, and plates between 2011 and 2020.

Quasi-2D Bi0.775Ln0.225O1.5 (Ln = La, Pr, Nd, Sm, Eu): reversible iodine intercalation and their evaluation as the anode in the lithium-ion battery system.

Layered materials with a robust structure and reversible intercalation behavior are highly sought-after in applications involving energy conversion and storage systems, energy converting devices, supercapacitors, batteries, superconductors, photonic materials, and catalysis involving hydrogen evolution reaction (HER), oxygen evolution reaction (OER), oxygen reduction reaction (ORR), solar cells and sensors. In the current study, quasi-2D rhombohedral Bi0.775Ln0.225O1.5 (Ln = La, Pr, Nd, Sm, and Eu) samples, synthesized by a solution combustion route, have been demonstrated to intercalate iodine reversibly. A solid-vapor reaction was employed to intercalate iodine at moderate temperatures, and deintercalation occurred on heating at higher temperatures. Expansion of the rhombohedral c-axis by ∼10 Å occurred, and the iodine between the interlayers existed as triiodide ions (I3-) in an unsymmetrical fashion. The amount of intercalated iodide has been determined from thermogravimetric analysis. Electron microscopic analysis confirmed these systems' intercalation and subsequent lattice expansion. In the diffuse reflectance spectra, charge transfer from the triiodide ions to the host oxide was noticed, and it caused the absorption edge to fall beyond the visible region for the intercalated samples. XPS analysis of iodine intercalated Bi0.775Pr0.225O1.5 has shown the mixed valence states for Pr and the existence of I3- along with some IO3- species. The quasi-2D structure was stable during the thermal deintercalation process. The evaluation of iodine intercalated Bi0.775Ln0.225O1.5 (Ln = La, Pr, Nd, Sm, and Eu) samples as anode material in the lithium-ion battery system has given quite promising results, exhibiting fast Li+-ion diffusion, low charge transfer resistance, good reversible capacity, capacity retention (after cycling back to 10 mA g-1), and structural stability (after long cycles).

Кратковременная топливная коррекция бензинового двигателя по напряжению датчика кислорода в процессе эксплуатации автомобиля

The object of the study was fuel trim of the air-fuel mixture, in particular, short-term fuel trim by voltage change of the oxygen sensor installed before the catalytic converter during vehicle operation. Experimental studies were on the Bishkek – Osh (Kyrgyz Republic) highway at an altitude of 750–3200 m above sea level. It is characterized by flat, mountainous and high mountainous vehicle operating conditions. The experimental studies results were used to graph the dependence of short-term fuel trim on the change of oxygen sensor voltage during vehicle operation. The values of fuel trim parameters can be used to assess the state of the air-fuel mixture, as well as to make a conclusion about the technical condition of sensors, systems and mechanisms of the engine and elements of the car exhaust system. In addition, in normal operation of the engine, when the fluctuation of fuel correction indicators is ±10 %, fuel-economic and environmental indicators will be in fit. It should also be recognized that the modern automobile engines have a system of various sensors and electronic engine control unit, but they have their certain disadvantages in ensuring the stoichiometric composition of the air-fuel mixture (λ = 1).

Spatially resolved quantification of oxygen consumption rate in ex vivo lymph node slices.

Cellular metabolism has been closely linked to activation state in cells of the immune system, and the oxygen consumption rate (OCR) in particular serves as a valuable metric for assessing metabolic activity. Several oxygen sensing assays have been reported for cells in standard culture conditions. However, none have provided a spatially resolved, optical measurement of local oxygen consumption in intact tissue samples, making it challenging to understand regional dynamics of consumption. Therefore, here we established a system to monitor the rates of oxygen consumption in ex vivo tissue slices, using murine lymphoid tissue as a case study. By integrating an optical oxygen sensor into a sealed perfusion chamber and incorporating appropriate correction for photobleaching of the sensor and of tissue autofluorescence, we were able to visualize and quantify rates of oxygen consumption in tissue. This method revealed for the first time that the rate of oxygen consumption in naïve lymphoid tissue was higher in the T cell region compared to the B cell and cortical regions. To validate the method, we measured OCR in the T cell regions of naïve lymph node slices using the optical assay and estimated the consumption rate per cell. The predictions from the optical assay were similar to reported values and were not significantly different from those of the Seahorse metabolic assay, a gold standard method for measuring OCR in cell suspensions. Finally, we used this method to quantify the rate of onset of tissue hypoxia for lymph node slices cultured in a sealed chamber and showed that continuous perfusion was sufficient to maintain oxygenation. In summary, this work establishes a method to monitor oxygen consumption with regional resolution in intact tissue explants, suitable for future use to compare tissue culture conditions and responses to stimulation.

Photosensitizer-singlet oxygen sensor conjugated silica nanoparticles for photodynamic therapy and bioimaging.

Intracellular singlet oxygen (1O2) generation and detection help optimize the outcome of photodynamic therapy (PDT). Theranostics programmed for on-demand phototriggered 1O2 release and bioimaging have great potential to transform PDT. We demonstrate an ultrasensitive fluorescence turn-on sensor-sensitizer-RGD peptide-silica nanoarchitecture and its 1O2 generation-releasing-storing-sensing properties at the single-particle level or in living cells. The sensor and sensitizer in the nanoarchitecture are an aminomethyl anthracene (AMA)-coumarin dyad and a porphyrin or CdSe/ZnS quantum dots (QDs), respectively. The AMA in the dyad quantitatively quenches the fluorescence of coumarin by intramolecular electron transfer, the porphyrin or QD moiety generates 1O2, and the RGD peptide facilitates intracellular delivery. The small size, below 200 nm, as verified by scanning electron microscopy and differential light scattering measurements, of the architecture within the 1O2 diffusion length enables fast and efficient intracellular fluorescence switching by the tandem ultraviolet (UV)-visible or visible-near-infrared (NIR) photo-triggering. While the red emission and 1O2 generation by the porphyrin are continually turned on, the blue emission of coumarin is uncaged into 230-fold intensity enhancement by on-demand photo-triggering. The 1O2 production and release by the nanoarchitecture enable spectro-temporally controlled cell imaging and apoptotic cell death; the latter is verified from cytotoxic data under dark and phototriggering conditions. Furthermore, the bioimaging potential of the TCPP-based nanoarchitecture is examined in vivo in B6 mice.

Formation of oxygen protective layer on monolayer MoS2 via low energy electron irradiation.

Monolayer molybdenum disulfide (MoS2) semiconductors are the new generation of two-dimensional materials that possess several advantages compared to graphene due to their tunable bandgap and high electron mobility. Several approaches have been used to modify their physical properties for optical device applications. Here, we report a facile and non-destructive surface modification method for monolayer MoS2 via electron irradiation at a low, 5 kV accelerating voltage. After electron irradiation, the results of Raman and photoluminescence spectroscopy confirmed that the structure remains unchanged. However, when the modified surface was illuminated with a 532 nm laser for a prolonged period, the PL intensity was quenched as a result of oxygen desorption. Interestingly, the PL intensity can be recovered when left in ambient conditions for 10 h. The analysis of the PL spectrum revealed a decrease of trion, which is consistent with the readsorbed O2 molecules on the surface that deplete electrons and lead to PL recovery. We attribute this effect to the enhancement of the n-type character of monolayer MoS2 after electron irradiation. The sensitive nature of the modified surface to oxygen suggests that this approach may be used as a tool for the fabrication of MoS2 oxygen sensors.

Oxomer- and Reporter Gene-Based Analysis of FIH Activity in Cells.

Cellular and tissue adaptations to oxygen deprivation (hypoxia) are necessary for both normal physiology and disease. Responses to hypoxia are initiated by the cellular oxygen sensors prolyl-4-hydroxylase domain (PHD) proteins 1-3 and factor inhibiting HIF (FIH). These enzymes regulate the transcription factor hypoxia-inducible factor (HIF) in a hypoxia-sensitive manner. FIH also regulates proteins outside the HIF pathway, including the deubiquitinase OTUB1. Numerous preclinical analyses have demonstrated thattreatment with HIF hydroxylase inhibitors is beneficial and protective in many hypoxia-associated diseases. However, clinically available HIF hydroxylase inhibitors increase erythropoietin (EPO) gene expression and red blood cell production, which can be detrimental in hypoxia-associated conditions, such as ischemia/reperfusion injury of the heart or chronic inflammation. Our understanding of the relevance of FIH in (patho)physiology is only in its infancy, but FIH activity does not govern erythropoietin expression. Therefore, it is of prime interest to assess the relevance of FIH activity in (patho)physiology in detail, as it may contribute to developing novel therapeutic options for treating hypoxia-associated diseases that do not affect Epo regulation. Here, we describe specific protocols for two different methods to assess FIH enzymatic activity within cells, using a HIF-dependent firefly luciferase-reporter gene and an oxomer-dependent assay. Oxomers are oxygen-dependent stable protein oligomers formed by FIH, for example, with the deubiquitinase OTUB1. Oxomer formation directly depends on FIH activity, providing a suitable cellular readout for an easy-to-use analysis of FIH enzymatic activity in cellulo. These techniques permit an analysis of FIH activity toward HIF and outside the HIF pathway, allowing the investigation of FIH activity under different (patho)physiological conditions and assessment of novel (putative) inhibitors.

Bamboo-like carbon nanotube composites containing cobalt nanoparticles combined with imidazole-based ionic liquids enhance the performance of oxygen sensors

In this study, BMIMPF6 was modified by adding BCNT/Co to it. The BCNT/Co + BMIMPF6 electrolyte system reduced the sensor response time to 16 s and showed good linearity in the range of 0–60% oxygen concentration.

Prolyl hydroxylase domain enzyme PHD2 inhibits proliferation and metabolism in non-small cell lung cancer cells in HIF-dependent and HIF-independent manners.

Prolyl hydroxylase domain protein 2 (PHD2) is one of the intracellular oxygen sensors that mediates proteasomal degradation of hypoxia-inducible factor (HIF)-α via hydroxylation under normoxic conditions. Because of its canonical function in the hypoxia signaling pathway, PHD2 is generally regarded as a tumor suppressor. However, the effects of PHD2 in tumorigenesis are not entirely dependent on HIF-α. Based on analysis of data from the Cancer Genome Atlas (TCGA) database, we observed that the expression of PHD2 is upregulated in non-small cell lung cancer (NSCLC), which accounts for approximately 80-85% of lung cancers. This suggests that PHD2 may play an important role in NSCLC. However, the function of PHD2 in NSCLC remains largely unknown. In this study, we established PHD2-deficient H1299 cells and PHD2-knockdown A549 cells to investigate the function of PHD2 in NSCLC and found that PHD2 suppresses cell proliferation and metabolism but induces ROS levels in human NSCLC cells. Further results indicated that the function of PHD2 in NSCLC is dependent on its enzymatic activity and partially independent of HIF. Moreover, we performed RNA-sequencing and transcriptomic analysis to explore the underlying mechanisms and identified some potential targets and pathways regulated by PHD2, apart from the canonical HIF-mediated hypoxia signaling pathway. These results provide some clues to uncover novel roles of PHD2 in lung cancer progression.

Hybrid Power Source in Fish Farming With Help of IoT Technology

Fish farming is a difficult, task that involves growing fish without risk. Maintaining the pond's water quality allows for safe fish production. This will go over the creation of a real-time water quality system to monitor fish farms. The water quality monitoring system includes a dissolved oxygen sensor, a pH sensor, and a water temperature sensor. The Arduino Nano microcontroller is linked with the Internet of Things (IoT) platform to provide real-time remote water monitoring. The system is intended to efficiently monitor water quality in freshwater fish farms, specifically water parameters suitable for fish. Instead of testing the system in the real fish farm, it is tested using water that is simulated to the water quality for the fish farm. If the water was above and below the fixed parameter it gives us an alert and water exchange mechanism get started by remove the dirty water from the pond through the solenoid valve and provide the fresh water into the pond. By measuring the dissolved oxygen level if is any deviation occurs water circulation mechanism should be established and circulate the water for increasing the oxygen level by using the padding wheel which all these done automatically. It also done the automatic food feeding at the periodic interval time without the manual involvement sometimes it may cause a manual error such as underfeeding and overfeeding which may affect the fish health to reduce such stuffs we use this automatic food feeding system. Keywords: Fish farming; IoT; Solar energy; Solar PV.

Acute Hyperoxia Improves Spinal Cord Oxygenation and Circulatory Function Following Cervical Spinal Cord Injury in Rats.

Spinal cord injury is associated with spinal vascular disruptions that result in spinal ischemia and tissue hypoxia. This study evaluated the therapeutic efficacy of normobaric hyperoxia on spinal cord oxygenation and circulatory function at the acute stage of cervical spinal cord injury. Adult male Sprague Dawley rats underwent dorsal cervical laminectomy or cervical spinal cord contusion. At 1-2 days after spinal surgery, spinal cord oxygenation was monitored in anesthetized and spontaneously breathing rats through optical recording of oxygen sensor foils placed on the cervical spinal cord and pulse oximetry. The arterial blood pressure, heart rate, blood gases, and peripheral oxyhemoglobin saturation were also measured under hyperoxic (50% O2) and normoxic (21% O2) conditions. The results showed that contused animals had significantly lower spinal cord oxygenation levels than uninjured animals during normoxia. Peripheral oxyhemoglobin saturation, arterial oxygen partial pressure, and mean arterial blood pressure are significantly reduced following cervical spinal cord contusion. Notably, spinal oxygenation of contused rats could be improved to a level comparable to uninjured animals under hyperoxia. Furthermore, acute hyperoxia elevated blood pressure, arterial oxygen partial pressure, and peripheral oxyhemoglobin saturation. These results suggest that normobaric hyperoxia can significantly improve spinal cord oxygenation and circulatory function in the acute phase after cervical spinal cord injury. We propose that adjuvant normobaric hyperoxia combined with other hemodynamic optimization strategies may prevent secondary damage after spinal cord injury and improve functional recovery.

Highly sensitive detection of oxygen based on light-induced thermoelastic spectroscopy with a high power diode laser

Oxygen (O2) is a fundamental element in the atmosphere. It is important to detect it in various fields. In this paper, a sensitive O2 sensor based on light-induced thermoelastic spectroscopy (LITES) with a high power diode laser is reported. A distributed feedback (DFB) diode laser emitting at 760 nm with output power of 16.8 mW was employed as the light source. The O2 absorption line at 13144.54 cm-1 was selected for the investigation. Wavelength modulation spectroscopy (WMS) technique and second harmonic signal demodulation (2f) were adopted to improve the sensing performance. For the concentration dynamic range from 20% to 80%, a linear relationship between the amplitude of 2f signal and O2 concentration was demonstrated. Allan deviation analysis was conducted to evaluate the long-term stability of the sensor system and the minimum detection limit (MDL) was measured to be 583 ppm at the optimum integration time of 100 s. Further improvement of this O2-LITES sensor system was also discussed.

Synthesis of gold nanoparticles with allicin to modify boron-doped diamond surface for oxygen sensor applications

Modification of surface of boron-doped diamond (BDD) film with gold nanoparticles (AuNPs) was carried out to increase its catalytic activity for an application as an oxygen sensor. Allicin was isolated from garlic by salting out extraction technique, and then used as the capping agent to synthesize AuNPs as it has a double bond structure that could be reacted to attach the BDD surface under UV light radiation. An average size of AuNPs at around 46,00 ± 9,06 nm was obtained, while the modification of the BDD surface by the synthesized AuNPs indicated that the surface of BDD could be covered by gold at around 0.6 % (w/w). Investigation of the AuNPs-modified BDD as a working electrode for the oxygen reduction by using cyclic voltammograms in 0.1 M phosphate buffer solution pH 7 observed a current peak at around -0.45 V (vs. Ag/AgCl). The current of this peak linearly increased proportionally to the dissolved oxygen concentrations (R2=0.9986). Moreover, a limit of detection of the dissolved oxygen of 0.12 ppm and limit of quantity 0.41 ppm could be achieved with excellent stability at 6.86% RSD with 6 repetitions and sensitivity at 19.086 μA/ppm indicated that the modified BDD is promising for applications as an oxygen sensor.

Membraneless Ionic Liquid Droplet Nanoprobe for Vapor Sensing and Gas Phase Scanning Electrochemical Microscopy

Gas phase sensing of volatile chemicals is a critical area of research relevant to biomedical diagnosis and environmental hazard assessment. Among various types of sensors, electrochemical sensors garnered attention as cost-effective and portable methods. Most electrochemical sensors needed the membrane to prevent solvent evaporation for detecting the gaseous species. However, the presence of the membrane induced slow response time due to the penetration of gas molecules through the membrane. To improve the systems, a membraneless ionic liquid droplet nanoprobe was developed. Gaseous species can permeate the thin ionic liquid layer, which was also used as the electrolytes, and react on the electrode in extremely fast response. Furthermore, nano-sized electrode makes available to detect sensitively with low charging capacitance. Using the probe type form factor, application to gas phase scanning electrochemical microscopy (SECM) was attempted with high spatial resolution. Oxygen detection, the most commonly studied, was implemented for the first application of the ionic liquid nanoprobe. The limit of detection of this probe was 13 ppm, which is extremely good for electrochemical oxygen sensors. Also, the fast response (< 0.1 s) made the mapping of oxygen concentration using SECM. The nanoprobe showed more than a hundred times better spatial resolution (several micrometer scale) than the previous gas phase SECM study mapping the oxygen. As the application of this oxygen probe, Li-air battery analysis can be conducted. Oxygen was used in the reaction at the cathode of the Li-air battery. As mapping the oxygen concentration above the cathode, It is expected that structural causes for the irreversibility at the cathode can also be found. As oxygen sensing, other electrochemical active gaseous species can be detected with the electrochemical sensor. Trinitrotoluene is a well-known explosive compound, and it can be detected in electrochemistry. Due to its low vapor pressure, di-nitroaromatic compounds, like dinitrotoluene (DNT), dinitrobenzene (DNB), and dinitrophenol (DNP), were used as explosive footprints, which have higher vapor pressure and have often been identified as marker molecules. Using our ionic liquid nanoprobe, we developed the nitroaromatic compounds (NACs) sensor for real-time detection of trace vapors, without any sample pre-treatment and at room temperature. Furthermore, in a simulated airport carousel, real-time and preemptive NACs detection was demonstrated with fast response time. As oxygen detection, gas phase SECM was conducted and 3D mapping capability of the differential vapor pressure was demonstrated, exercising the potential of the NACs nanoprobe in locating the source of an explosive risk. With the sensitive sensing performance of nanoprobe, it can be used as breath analysis. There are several biomarkers to indicate certain diseases. For example, acetone is a representative biomarker of diabetes. Using this sensing platform, acetone sensing was implemented, and it may be used for the initial detection of diabetes.