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- 摘要
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- 实验方案
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[IEEE NAECON 2018 - IEEE National Aerospace and Electronics Conference - Dayton, OH, USA (2018.7.23-2018.7.26)] NAECON 2018 - IEEE National Aerospace and Electronics Conference - Ultrasensitive label-free tobramycin detection with aptamer-functionalized ZnO TFT biosensor
摘要： Aminoglycoside antibiotic such as tobramycin is critical to the treatment of Gram-negative bacterial diseases such as Cystic Fibrosis (Pseudomonas aeruginosa) and other respiratory problems routinely seen in military personnel. Bottom gate (BG) zinc oxide (ZnO) ultra-thin film transistors (TFTs) were fabricated and functionalized with thiol-anchored aptamers as sensitive tobramycin biosensors and a Lower Detection Limit (LDL) of 0.1 nM was extracted from the adsorption coverage isotherm. Sputter deposition of ZnO allows the control of film thickness, stoichiometry, defects and interface states. Intrinsically high surface morphology of ZnO allows improved aptamer functionalization and sensitivity of detection.
关键词： tobramycin,functionalization,biosensor,sputter deposition,aptamer,cystic fibrosis,thin film transistor,ZnO
更新于2025-09-23 15:22:29
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[IEEE 2018 International Semiconductor Conference (CAS) - Sinaia, Romania (2018.10.10-2018.10.12)] 2018 International Semiconductor Conference (CAS) - Carbon Nanotube/Polyaniline Composite Films Prepared by Hydrothermal- Electrochemical Method for Biosensor Applications
摘要： In this study, CNT-PANI composites were prepared in soft chemical synthesis conditions using hydrothermal method. Our aim is to obtain CNT-PANI films with potential applications in VOC’s detection, using an environmental friendly, low energy consumption technique: hydrothermal-electrochemical deposition of composite films. Thin films were characterized by AFM and FT-IR analyses.
关键词： carbon nanotubes,poly(aniline),composites,biosensor,electrochemical
更新于2025-09-23 15:22:29
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A photoelectrochemical glucose and lactose biosensor consisting of gold nanoparticles, MnO2 and g-C3N4 decorated TiO2
摘要： In this study, an innovative light-sensitive hybrid material was used for photoelectrochemical (PEC) biosensor fabrication. Herein, gold nanoparticles modified mesoporous TiO2 was coated on an indium tin oxide substrate, after a layer of MnO2/g-C3N4 was introduced to develop a PEC biosensor that yielded a favorable electronic interface for photo-excited electron injection. Glucose oxidase and β-galactosidase were co-immobilized on the photoanode surface via silane/glutaraldehyde linkage chemistry for glucose and lactose determination. Au NPs, g-C3N4, and MnO2 were utilized to modify quintessential semiconductor TiO2 owing to their narrow band gaps, appropriate position of the valence and conduction bands, and high visible light absorption. The p–n heterojunction formation at the interface of MnO2 and g-C3N4/TiO2 was presumed, and the heterojunction facilitates the charge transport and inhibit the recombination of excited electrons. Direct electron transfer led to the hole scavenging by FADH2, which reinforced the photocurrent. The linear measurement ranges were calculated in the range of 0.004-1.75 mM, with a sensitivity of 1.54 μAmM?1cm?2 for glucose at 0 V, and 0.008-2.50 mM, with a sensitivity of 1.66 μAmM?1cm?2 for lactose at -0.4 V. To the best of our knowledge, we report the first PEC lactose biosensor, and this study opens the door to PEC multianalyte detection.
关键词： β-galactosidase,g-C3N4,Self-powered biosensor,Glucose oxidase,Gold nanoparticles
更新于2025-09-23 15:21:21
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Optimized Bent Part Coupling SiON Racetrack Resonators for Biological Sensing
摘要： In this work, we investigate the optimized parameters of bent part coupling silicon oxynitride (SiON) micro racetrack optical resonators coupled to a straight waveguide, for an efficient design of label free biosensor devices. A systematic engineering of waveguide-resonator characteristics, for optimum geometry and field-overlap with analytes is proposed. Different parameters of system such as coupling, intrinsic and total quality factors of Qκ , Qi, and Qt, sensitivity (S) and figure of merit (F OM ) or intrinsic limit of detection (ILOD), are examined with interest of taking into account the dispersion effect in calculations. To the best of our knowledge, considering dispersion effect in calculations, has been proposed for the first time in bent part coupling racetrack resonator based biosensors. We have shown the effective role of dispersion on the best optimized parameters of the biosensors. These investigations result in high amounts of S (435 nm/RIU) and Qt (≥45000), simultaneously for the proposed biosensors. The devices have been optimized for operation at wavelength of 850 nm. The biosensing performance of our biosensor, is compared with lately reported theoretical and experimental investigations. Based on the ILOD calculations, performance of our sensor structure, is improved by a factor of 0.10 compared to a resonator based biosensor, reported lately.
关键词： sensitivity,biosensor device,Dispersion,bent part coupling racetrack resonator,ILOD
更新于2025-09-23 15:21:21
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Quantification of DNA by a Thermal-Durable Biosensor Modified with Conductive Poly(3,4-ethylenedioxythiophene)
摘要： The general clinical procedure for viral DNA detection or gene mutation diagnosis following polymerase chain reaction (PCR) often involves gel electrophoresis and DNA sequencing, which is usually time-consuming. In this study, we have proposed a facile strategy to construct a DNA biosensor, in which the platinum electrode was modified with a dual-film of electrochemically synthesized poly(3,4-ethylenedioxythiophene) (PEDOT) resulting in immobilized gold nanoparticles, with the gold nanoparticles easily immobilized in a uniform distribution. The DNA probe labeled with a SH group was then assembled to the fabricated electrode and employed to capture the target DNA based on the complementary sequence. The hybridization efficiency was evaluated with differential pulse voltammetry (DPV) in the presence of daunorubicin hydrochloride. Our results demonstrated that the peak current in DPV exhibited a linear correlation the concentration of target DNA that was complementary to the probe DNA. Moreover, the electrode could be reused by heating denaturation and re-hybridization, which only brought slight signal decay. In addition, the addition of the oxidized form of nicotinamide adenine dinucleotide (NAD+) could dramatically enhance the sensitivity by more than 5.45-fold, and the limit-of-detection reached about 100 pM.
关键词： poly(3,4-ethylenedioxythiophene),gold nanoparticle,electron transfer mediate,DNA biosensor
更新于2025-09-23 15:21:21
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A Fluidic Interface with High Flow Uniformity for Reusable Large Area Resonant Biosensors
摘要： Resonant biosensors are known for their high accuracy and high level of miniaturization. However, their fabrication costs prevent them from being used as disposable sensors and their effective commercial success will depend on their ability to be reused repeatedly. Accordingly, all the parts of the sensor in contact with the ?uid need to tolerate the regenerative process which uses different chemicals (H3PO4, H2SO4 based baths) without degrading the characteristics of the sensor. In this paper, we propose a ?uidic interface that can meet these requirements, and control the liquid ?ow uniformity at the surface of the vibrating area. We study different inlet and outlet channel con?gurations, estimating their performance using numerical simulations based on ?nite element method (FEM). The interfaces were fabricated using wet chemical etching on Si, which has all the desirable characteristics for a reusable biosensor circuit. Using a glass cover, we could observe the circulation of liquid near the active surface, and by using micro-particle image velocimetry (μPIV) on large surface area we could verify experimentally the effectiveness of the different designs and compare with simulation results.
关键词： micro-machining,microengineering,biosensor,?uidic interface,planar ?ow
更新于2025-09-23 15:21:21
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Point-of-care Colorimetric Analysis through Smartphone Video
摘要： Point-of-care (POC) tests often rely on smartphone image methods for colorimetric analysis, but the results of such methods are frequently difficult to reproduce or standardize. The problem is aggravated by unpredictable image capture conditions, which pose a significant challenge when low limits of detection (LOD) are needed. Application-specific smartphone attachments are often used to standardize imaging conditions, but there has recently been an interest in equipment-free POC colorimetric analysis. Improved output metrics and preprocessing methods have been developed, but equipment-free imaging often has a high LOD and is inappropriate for quantitative tasks. Additional work is necessary to replace external smartphone attachments with algorithms. Towards this end, we have developed a video processing method that synthesizes many images into a single output metric. We use image features to select the best inputs from a large set of video frames and demonstrate that the resulting output values have a stronger correlation with laboratory methods and a lower standard error. The developed algorithm only requires 20 seconds of video and can easily be integrated with existing processing methods. We apply our algorithm to the NS1-based sandwich ELISA for Zika detection and show that the LOD is two times lower when our video-based method is used.
关键词： Smartphone,Point of care,Zika Detection,Cell phone,Biosensor
更新于2025-09-23 15:21:21
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[IEEE 2019 28th Wireless and Optical Communications Conference (WOCC) - Beijing, China (2019.5.9-2019.5.10)] 2019 28th Wireless and Optical Communications Conference (WOCC) - Copyright Page
摘要： We experimentally demonstrate a surface-plasmon-resonance-based sensor capable of detecting polysaccharide molecules, such as Xanthan gum. Experimental results demonstrate that by attaching Concanavalin A to the gold nanothin-film chip of the sensor, a linear response of the change in reflected optical power to the dissolved Xanthan gum concentration is observed, demonstrating the ability of the developed sensor to detect Xanthan gum concentrations up to 0.22 g/L.
关键词： surface plasmon resonance,desalination,Biosensor,optical sensors,xanthan gum
更新于2025-09-23 15:21:01
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Laser induced self-N-doped porous graphene as an electrochemical biosensor for femtomolar miRNA detection
摘要： We report a sensitive, yet low-cost biosensor based on laser induced graphene for femtomolar microRNA (miRNA) detection. Combined with the miRNA extraction and magnetic isolation process, the target miRNAs were purified for further detection using laser induced graphene sensor. The laser induced graphene was prepared by direct laser writing on commercial polyimide (PI) and patterned via a computer-aided design system as an electrode for electrochemical biosensing. We found that the laser reduction of PI resulted in nitrogen-doped porous graphene, not only improving its conductivity but also its sensitivity to nucleic acids. Preeclampsia specific miRNA hsa-miR-486-5p was magnetically purified and directly adsorbed on the surface of graphene electrode via graphene-miRNA affinity interaction. Surface attached miRNAs were then electrochemically quantified using [Fe(CN)6]3-/4- redox system. Our assay demonstrates detection of miRNA has-miR-486-5p up to concentrations as low as 10 fM with excellent reproducibility. Owing to its facile fabrication, low cost and high performance, the laser induced N-doped graphene biosensor presented here shows great potential for applications in detecting miRNA in biomedical applications.
关键词： electrochemical biosensor,porous graphene,laser induced graphene,nitrogen-doped,miRNA detection
更新于2025-09-23 15:21:01
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Laser-Induced Graphene Electrochemical Immunosensors for Rapid and Label-Free Monitoring of <i>Salmonella enterica</i> in Chicken Broth
摘要： Food-borne illnesses are a growing concern for the food industry and consumers, with millions of cases reported every year. Consequently, there is a critical need to develop rapid, sensitive, and inexpensive techniques for pathogen detection in order to mitigate this problem. However, current pathogen detection strategies mainly include time-consuming laboratory methods and highly trained personnel. Electrochemical biosensors offer a rapid, low-cost alternative to laboratory techniques, but the electrodes used in these biosensors require expensive nanomaterials to increase their sensitivity, such as noble metals (e.g., platinum, gold) or carbon nanomaterials (e.g., carbon nanotubes, or graphene). Herein, we report the fabrication of a highly sensitive and label-free laser-induced graphene (LIG) electrode that is subsequently functionalized with antibodies to electrochemically quantify the food-borne pathogen Salmonella enterica serovar Typhimurium. The LIG electrodes were produced by laser induction on the polyimide film in ambient conditions and, hence, circumvent the need for high-temperature, vacuum environment, and metal seed catalysts commonly associated with graphene-based electrodes fabricated via chemical vapor deposition processes. After functionalization with Salmonella antibodies, the LIG biosensors were able to detect live Salmonella in chicken broth across a wide linear range (25 to 105 CFU mL?1) and with a low detection limit (13 ± 7 CFU mL?1; n = 3, mean ± standard deviation). These results were acquired with an average response time of 22 min without the need for sample preconcentration or redox labeling techniques. Moreover, these LIG immunosensors displayed high selectivity as demonstrated by nonsignificant response to other bacteria strains. These results demonstrate how LIG-based electrodes can be used for electrochemical immunosensing in general and, more specifically, could be used as a viable option for rapid and low-cost pathogen detection in food processing facilities before contaminated foods reach the consumer.
关键词： biosensor,foodborne pathogens,graphene,food safety,Salmonella Typhimurium,electrochemical impedance spectroscopy
更新于2025-09-23 15:21:01