Frontiers in sensors最新文献

{"title":"Sensing and Stimulating Electrodes for Electroceuticals","authors":"Xiao Liu, Kezhong Wang, M. A. González-González, M. Romero-Ortega, G. Wallace","doi":"10.3389/fsens.2022.873862","DOIUrl":"https://doi.org/10.3389/fsens.2022.873862","url":null,"abstract":"Electroceuticals is an emerging field that combines the technology in conductive materials with their ability to interface with biological systems. The development of highly conductive electrodes to monitor human health in real-time while simultaneously delivering stimulation promises to revolutionize medical science. Aspects to consider during development include the desired shape, electrode material properties, number of active sites, carriers used, and methods of deployment and activation. Novel organic-conductor based electrode compositions offer properties unattainable with conventional metal electrodes. Emerging innovative deployment strategies communicate directly with target tissues while minimizing damage to the surrounding biological environment. Here we highlight the recent reported technology on platinized graphene fibers (sutrode), a high performance electrode, capable of recording electrophysiological signals from small autonomic nerves, which could bring us closer to the ultimate goal: modulating the activity of individual organs with high selectivity and precision for a therapeutic medical outcome. An in-depth understanding of electrode materials and methods of fabrication and deployment can provide unprecedented opportunities for electroceutical research.","PeriodicalId":93754,"journal":{"name":"Frontiers in sensors","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46942464","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exfoliated Graphite: A Surface Renewed Electrode for Environmental Applications","authors":"A. Idris, B. Orimolade, Mafa Potlako, Usisipho Feleni, T. Nkambule, B. Mamba","doi":"10.3389/fsens.2022.861965","DOIUrl":"https://doi.org/10.3389/fsens.2022.861965","url":null,"abstract":"Exfoliated graphite is a 2D carbon material that has recently received great attention owing to its remarkable analytical merits such as fast electron migration, ease of surface regeneration, high-temperature resistance, ability to withstand high-current density, excellent conductivity, and sensitivity. Due to its excellent analytical signature, an exfoliated graphite electrode has been reportedly used in the construction of sensors and biosensors for various applications. This electrode can be used alone or blended with several nanomaterials/semiconductors for the degradation of various organic pollutants in wastewater. Despite the outstanding results reported in the use of exfoliated graphite electrodes for various analytical applications, very few reports were documented in the literature. Therefore, this review elaborated on the importance of exfoliated graphite electrodes for electrochemical analysis.","PeriodicalId":93754,"journal":{"name":"Frontiers in sensors","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45646117","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dual-Parameter Sensing With a Single Supermode Interferometer","authors":"J. A. Flores-Bravo, J. Villatoro","doi":"10.3389/fsens.2022.820612","DOIUrl":"https://doi.org/10.3389/fsens.2022.820612","url":null,"abstract":"Optical fiber interferometers have intrinsic sensitivity to temperature, thus, in sensing applications; they need a reference temperature sensor or a mechanism to control the temperature. Here, we demonstrate that a single multicore fiber interferometer can monitor two parameters simultaneously; more particularly, refractive index, and temperature. The interferometer is easy to manufacture; a short segment of an optical fiber with seven coupled cores is fusion spliced at the distal end of a conventional single mode optical fiber. In the coupled-core fiber, two supermodes beat; this makes the reflection spectrum of the device to exhibit a well-defined series of maxima and minima. The refractive index of a sample in contact with multicore fiber alters the amplitude of the interference pattern and temperature induces a shift to such a pattern. The changes of the interference pattern are easy to monitor and decode with a low-resolution spectrometer. As an application of our dual-parameter sensor, the thermo-optic coefficient of a sample was measured.","PeriodicalId":93754,"journal":{"name":"Frontiers in sensors","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45480525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ultra-Long Range Refractive Index Fiber Sensor","authors":"Carmen E. Domínguez-Flores, Alessandra I. Valdés-Hernández, Ana Karen Reyes, D. Monzón-Hernández, Osvaldo Rodríguez-Quiroz, R. Ochoa-Valiente","doi":"10.3389/fsens.2022.855251","DOIUrl":"https://doi.org/10.3389/fsens.2022.855251","url":null,"abstract":"The dynamic range of optical fiber refractive index sensors is mainly determined by the refractive index (RI) of the sensor surface in contact with the sample under test. In case of the refractive index sensor based on the hybrid fiber Fabry–Perot interferometer (HFFPI), the largest measurable refractive index value is equal to that of the fiber core. In this work, we demonstrate that it is possible to extend the refractive index dynamic range of a HFFPI by simply adjusting the optical path length (OPL) of the air and solid cavity to be equal or differ by just a small amount. Two isometric versions of the HFFPI (i-HFFPI) with a total length of 100 and 172 μm, where the OPL of the air and solid cavity are very similar, were fabricated and tested. The interferometers were immersed in different samples with a refractive index ranging from 1.000 to 1.733. The response of the interferometers was analyzed in the Fourier domain, and it was possible to establish a one-to-one relationship between the refractive index of the liquid sample and the amplitude of one of the peaks in the Fourier spectra. The amplitude of this peak experienced a linear increment when the RI of the surrounding medium was increased. Tracking the amplitude changes of a Fourier spectrum peak is straightforward which simplifies the online monitoring of the sensor. These features make this compact refractive index fiber sensor very appealing for biosensing applications.","PeriodicalId":93754,"journal":{"name":"Frontiers in sensors","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42049600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Editorial: Emerging Technologies and Applications in Distributed Optical Fiber Sensors","authors":"D. Tosi, D. Barrera, L. Schenato","doi":"10.3389/fsens.2022.890452","DOIUrl":"https://doi.org/10.3389/fsens.2022.890452","url":null,"abstract":"In the framework of advancing the capabilities for sensing and the ubiquitous detection of parameters, distributed fiber-optic sensors have gained significant traction, as they can detect and spatially and temporally resolve physical quantities. They find increasing applications in structural health monitoring, aerospace, geotechnical engineering, and, more recently, in medical devices. The latest years have seen a shift towards distributed sensing with ultra-narrow scale, approaching millions of sensing points in the fiber, real-time detection, and abating the complexity of the optical hardware involved in the system. The Research Topic “Emerging Technologies and Applications in Distributed Optical Fiber Sensors” featured on Frontiers on Sensors journal reflects on the advancement of such technologies and provides a forum where recent trends have been presented as review and perspective formats: from engineering the design of the optical fibers to enhancing the detection methods, up to the actual applications in environmental sciences. The first article, presented by Sun et al. provides a bird-eye view of the methods and applications for in situ detection of the moisture field distribution using optical fiber distributed sensors. Fibers have been employed in distributed and quasi-distributed schemes for the detection of soil water content and for pore gas humidity; the combined measurement, with high-precision distributed networks provides a significant improvement in geotechnical engineering, moving from the lab to the actual on-site applications. A second work from Fernandez-Ruiz et al. reviews the latest improvement on distributed sensors from the hardware perspective through time-expanded phase optical time-domain reflectometry (TE-φOTDR). This innovative scheme allows achieving narrow, centimeter-level, spatial resolution with rapid sensing, taking inspiration from spectroscopy techniques that combine the light scattering with a spectral comb generated by a simple oscillator. The TEφOTDR finds applications in strain and temperature sensing as a potential relatively low-cost architecture. The final work, proposed by Lu et al., provides a perspective on the new design of high-scattering fibers optimized for short-scale distributed sensing. While traditional sensors make use of commercial, single-mode fibers (such as the SMF-28 standardized for communications), the possibility of doping the fiber core with nanoparticles induce giant increases of the intensity of the backscattered signal, that, Edited and reviewed by: Joel Villatoro, University of the Basque Country, Spain","PeriodicalId":93754,"journal":{"name":"Frontiers in sensors","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47673446","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Harnessing Fe3O4 Screen-Printed Modified Electrode Sensor for Detecting Epinephrine in Buff Orpington Rooster and Rhodes Island White Broiler","authors":"O. E. Fayemi, S. E. Elugoke, Oluwole Dina, M. Mwanza, P. O. Fayemi","doi":"10.3389/fsens.2022.850316","DOIUrl":"https://doi.org/10.3389/fsens.2022.850316","url":null,"abstract":"Nano-scale detection and characterization of neurotransmitters from real samples is a novel analytical technique with multiple applications in the field of nano-biotechnology. This in-situ electrochemical sensing tool has growing advantages of high reproducibility, rapid response, superior sensitivity, selectivity, accuracy, and miniaturization. A screen-printed iron oxide (Fe3O4) modified electrode was harnessed in this study for detecting epinephrine (EP), a chemical messenger or signalling neuro transmitting molecule, from two breeds of chickens. The fabricated sensor was used for the analysis of EP in the real and unspiked samples. UV-visible spectroscopy, Fourier-Transform infrared spectroscopy (FT-IR), Transmission Electron Microscopy (TEM), and Scanning Electron Microscopy (SEM) were used for characterizing the surface of nanoparticles prior to modification of screen-printed silver electrode (SPSE). The XRD diffractogram of Fe3O4 nanoparticles showed peaks at 30.1°, 35.7°, 43.3°, 53.9°, 57.5°, and 63.0°, corresponding to Miller indices of 220, 311, 400, 422, 511, and 440, respectively. This diffraction pattern indicates that the Fe3O4 nanoparticles have a spinel structure. Simultaneous detection of EP in the presence of ascorbic acid was obtained from Fe3O4 electrode. Further result shows a corresponding rise in oxidation peak current (Ipa) of EP with an increase in its concentration and scan rate of 25–400 mVs−1 confirming catalytic properties of the modified electrode towards EP. Our findings demonstrate that the fabricated sensor used for detecting EP in blood serum, breast muscle, and visceral organs of both chicken breeds produced better recovery.","PeriodicalId":93754,"journal":{"name":"Frontiers in sensors","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48384447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Graphic Carbon Nitride-SilverPolyvinylpyrrolidone Nanocomposite Modified on a Glassy Carbon Electrode for Detection of Paracetamol","authors":"N. Mekgoe, N. Mabuba, K. Pillay","doi":"10.3389/fsens.2022.827954","DOIUrl":"https://doi.org/10.3389/fsens.2022.827954","url":null,"abstract":"In this study a nanocomposite of graphitic carbon nitride-silver polyvinylpyrrolidone (gCN-AgPVP) was fabricated for the electrochemical detection of paracetamol (PAR). The nanocomposite of gCN-AgPVP showed superior electrocatalytic ability for PAR detection since it is selectively adsorbed by electrostatic interactions of the nanocomposite of gCN-AgPVP. This selective adsorption is also facilitated by charge assisted interactions between the PAR and gCN-AgPVP surfaces. The stability of the GCE/gCN-AgPVP was characterised using cyclic voltammetry (CV) at potentials ranging from −0.2 to +0.7 V and a scan rate of 50 mV/s. Square wave voltammetry (SQWV) was employed to characterise and detect PAR. The analysis was conducted on modified GCE/gCN-AgPVP in 0,1M phosphate buffer solution (PBS) and pH 6.1. GCE/gCN-AgPVP showed excellent performance in detecting PAR in the concentration range of 0.2–100 µM with a correlation coefficient of 0.9951 respectively. The calculated detection limit (LOD) was 0.079 µM.","PeriodicalId":93754,"journal":{"name":"Frontiers in sensors","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47538261","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Periodic Collapsed Solid-Core PCF Based Modal Interferometer for Chemical Sensing","authors":"J. Dash, R. Jha","doi":"10.3389/fsens.2022.865215","DOIUrl":"https://doi.org/10.3389/fsens.2022.865215","url":null,"abstract":"We experimentally demonstrated a periodically collapsed solid-core photonic crystal fiber (SCPCF) based modal interferometer for sensing refractive index (RI) of chemicals. A given piece of SCPCF is periodically collapsed using an easily and widely available commercial splicer machine and a micropositioner. The distance between the collapsed and number of collapsed regions can be controlled precisely by the inexpensive micropositioner. The effect of the number of periods on the RI sensitivity has been studied. Our experimental results show that this simple and easily fabricated interferometer has an RI sensitivity of 230 nm/RIU with negligible cross-temperature error.","PeriodicalId":93754,"journal":{"name":"Frontiers in sensors","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44421567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Toward Engineered Nanoparticle-Doped Optical Fibers for Sensor Applications","authors":"Zhuorui Lu, Thibaut Robine , C. Molardi, F. Pigeonneau, D. Tosi, W. Blanc","doi":"10.3389/fsens.2021.805351","DOIUrl":"https://doi.org/10.3389/fsens.2021.805351","url":null,"abstract":"Nanoparticle-doped optical fibers, investigated first as fiber lasers and fiber amplifiers, have gained tremendous interest over the past few years as fiber sensors. One of the main interests of such fibers relies on the ability to develop a distributed sensor, allowing real-time measurement with multiplexed architecture. To go beyond the actual proof of concept, we discuss in this perspective paper three main challenges to tackle: understanding light propagation in heterogeneous materials, controlling nanoparticle formation in glass, and engineering nanoparticle characteristics. Identified as the main directions to follow, they will contribute to promote nanoparticle-doped fiber sensors in the next few years.","PeriodicalId":93754,"journal":{"name":"Frontiers in sensors","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41927561","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance Characterization of Dosimeters Based on Radiation-Hard Silicon Diodes in Gamma Radiation Processing","authors":"C. C. Bueno, F. Camargo, J. Gonçalves, K. Pascoalino, A. Mangiarotti, E. Tuominen, J. Härkönen","doi":"10.3389/fsens.2022.770482","DOIUrl":"https://doi.org/10.3389/fsens.2022.770482","url":null,"abstract":"The dosimetric response of silicon diodes produced with distinct engineering technologies, Magnetic Czochralski (MCz), and standard Float Zone (Fz), has been investigated, aiming at their use for online dosimeters in gamma radiation processing applications. The p+-n-n+ junction diodes, 300 µm thick with an active area of 25 mm2, are operated as online radiation dosimeters in the short-circuit current mode. In this case, the key dosimetric quantity is the dose rate, which is correlated with the output current from the diode subjected to radiation. Thus, the dose is obtained offline by the integration of the corresponding current signal. The irradiations are performed with an industrial Gammacell 60Co facility at 2.3–2.44 kGy/h covering doses up to 275 kGy. Under continuous irradiation, both diodes delivered current signals whose intensities decreased with accumulated doses. Mitigation of this decay has been accomplished by pre-irradiating the devices to 700 kGy. Polynomial functions best represent the dose responses for either pristine or preirradiated diodes. The relevant dosimetric parameters as response stability, charge sensitivity, and repeatability of current signals (<5%) reveal the better performance of the MCz diode. It is important to note that the whole dataset fully complies with the international standard protocols for routine dosimeters in radiation processing dosimetry. Regarding radiation damage, which in unbiased diodes manifests primarily in the decay of current sensitivity, the results also showed greater tolerance of the MCz diode. Based on these studies, large availability, and better cost-effectiveness, it is possible to endorse the potential use of MCz devices as online routine dosimeters in radiation processing applications. However, the data reproducibility with the accumulated dose, the dose lifespan, and the effect of the irradiation conditions (e.g., temperature, relative humidity, and dose fractionating) remain to be investigated. Works in this direction are currently in progress.","PeriodicalId":93754,"journal":{"name":"Frontiers in sensors","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44510407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}