The Experts below are selected from a list of 26505 Experts worldwide ranked by ideXlab platform
A G Cullis - One of the best experts on this subject based on the ideXlab platform.
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ultra sensitive polysilicon wire glucose sensor using a 3 aminopropyltriethoxysilane and polydimethylsiloxane treated hydrophobic fumed silica nanoparticle mixture as the Sensing Membrane
Sensors and Actuators B-chemical, 2009Co-Authors: Poyen Hsu, Jingjenn Lin, Wenchang Hung, A G CullisAbstract:Abstract In this paper a highly sensitive glucose biosensor is proposed based on a polysilicon (poly-Si) wire structure coated with 3-aminopropyltriethoxysilane (γ-APTES) mixed with polydimethylsiloxane-treated hydrophobic fumed silica nanoparticles (NPs) as the Sensing Membrane. The γ-APTES and fumed silica NPs mixture was directly transferred to and coated onto the poly-Si wire region with the help of a focus-ion-beam (FIB) processed capillary atomic-force-microscope (C-AFM) tip. After the necessary curing and UV illumination processes, the resultant sensor showed an extremely wide linear detection range from 0.1 μM to 10 mM with a channel current sensitivity as high as 5.33 A mM−1 cm−2 (or a channel conductance sensitivity of 70 μS mM−1), and a detection limit as low as 10 nM can be achieved. Our experimental results showed that the poly-Si wire sensor has good selective analysis and operational stability on glucose detection under a 10:1 concentration ratio of glucose and uric acid. Its linear range and lowest detection limit remain virtually unimpaired in the presence of uric acid.
Hyunjune Jang - One of the best experts on this subject based on the ideXlab platform.
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electronic cortisol detection using an antibody embedded polymer coupled to a field effect transistor
ACS Applied Materials & Interfaces, 2018Co-Authors: Hyunjune Jang, Taein Lee, Jian Song, Luisa M Russell, Jennifer Dailey, Peter C Searson, Howard E KatzAbstract:A field-effect transistor-based cortisol sensor was demonstrated in physiological conditions. An antibody-embedded polymer on the remote gate was proposed to overcome the Debye length issue (λD). The Sensing Membrane was made by linking poly(styrene-co-methacrylic acid) (PSMA) with anticortisol before coating the modified polymer on the remote gate. The embedded receptor in the polymer showed sensitivity from 10 fg/mL to 10 ng/mL for cortisol and a limit of detection (LOD) of 1 pg/mL in 1× PBS where λD is 0.2 nm. A LOD of 1 ng/mL was shown in lightly buffered artificial sweat. Finally, a sandwich ELISA confirmed the antibody binding activity of antibody-embedded PSMA.
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highly sensitive electrolyte insulator semiconductor ph sensors enabled by silicon nanowires with al2o3 sio2 Sensing Membrane
Sensors and Actuators B-chemical, 2012Co-Authors: Hyunjune Jang, Wonju Cho, Saif M IslamAbstract:a b s t r a c t Low sensitivity and poor reliability currently limit the applications of solid-state bio-chemical sensors. We demonstrate an electrolyte-insulator-semiconductor (EIS) sensor with a large capacitance, near- Nernst-limit pH sensitivity, and good reliability by integrating an ensemble of Si nanowires (NWs) for the first time. The NWs were fabricated by using the electroless wet etching technique. An Al2O3/SiO2 bilayer coating was employed as a Sensing Membrane. The EIS sensors with 3.8 m long NWs exhibited about 8 times larger capacitance than that of a planar type EIS sensors that were fabricated using the same fabrication scheme without integrating NWs. The measured pH sensitivity at room temperature was 60.2 mV/pH, which is higher than the theoretical Nernstian of 59 mV/pH. Our results and analysis clearly indicate that ultra-sensitive pH Sensing can be realized with optimized NW integrated EIS sensors.
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high performance silicon on insulator based ion sensitive field effect transistor using high k stacked oxide Sensing Membrane
Applied Physics Letters, 2011Co-Authors: Hyunjune Jang, Wonju ChoAbstract:High performance ion-sensitive field-effect transistors (ISFETs) were realized using silicon-on insulator substrate (SOI) and engineered Sensing Membrane. The engineered Sensing Membrane for the gate oxide was proposed to improve the chemical stability and obtain the enhanced output signal by stacking SiO2/HfO2/Al2O3 (OHA) layers. The SOI-metal–oxide–semiconductor field effect transistor (MOSFET) with the OHA gate oxide showed a high on/off current ratio of 1.8 × 1010 and a low subthreshold swing of 65 mV/dec. The SOI based ISFET with the OHA Membrane exhibited a low drift rate of 0.23 mV/h, a low hysteresis width of 1.85 mV, and a high pH sensitivity level of 57.1 mV/pH.
Wonju Cho - One of the best experts on this subject based on the ideXlab platform.
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Semiconducting single-walled carbon nanotube network-based double-gate thin-film transistors for high-performance aqueous chemical sensor applications
AIP Publishing LLC, 2018Co-Authors: Eun-ki Hong, Wonju ChoAbstract:In this study, we fabricated a highly sensitive separative extended gate chemically modified field effect transistor (SEG-ChemFET) sensor using a semiconducting single-walled carbon nanotube (scSWCNT) network. To improve the stability and sensitivity of the scSWNT channel layer, we fabricated a double-gate structure FET transducer with a passivated channel using top- and bottom-gate insulators and applied a separate Sensing Membrane. The scSWCNT network channel was formed by solution process. In order to increase the sensitivity, a low-k spin-on-glass (SOG) film and a stacked Ta2O5/SiO2 film were formed as top-gate and engineered bottom-gate insulators, respectively, which improved the coupling ratio. As a result, the fabricated scSWCNT ChemFET sensor exhibited sensitivity of 365.65 mV/pH sensitivity, which is much higher than the Nernst limit (59.5 mV/pH), a linearity of 99.88%, and a drift rate of 72.44 mV/h. Thus, we expect this research to have important applications for high-sensitivity biosensors
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highly sensitive electrolyte insulator semiconductor ph sensors enabled by silicon nanowires with al2o3 sio2 Sensing Membrane
Sensors and Actuators B-chemical, 2012Co-Authors: Hyunjune Jang, Wonju Cho, Saif M IslamAbstract:a b s t r a c t Low sensitivity and poor reliability currently limit the applications of solid-state bio-chemical sensors. We demonstrate an electrolyte-insulator-semiconductor (EIS) sensor with a large capacitance, near- Nernst-limit pH sensitivity, and good reliability by integrating an ensemble of Si nanowires (NWs) for the first time. The NWs were fabricated by using the electroless wet etching technique. An Al2O3/SiO2 bilayer coating was employed as a Sensing Membrane. The EIS sensors with 3.8 m long NWs exhibited about 8 times larger capacitance than that of a planar type EIS sensors that were fabricated using the same fabrication scheme without integrating NWs. The measured pH sensitivity at room temperature was 60.2 mV/pH, which is higher than the theoretical Nernstian of 59 mV/pH. Our results and analysis clearly indicate that ultra-sensitive pH Sensing can be realized with optimized NW integrated EIS sensors.
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high performance silicon on insulator based ion sensitive field effect transistor using high k stacked oxide Sensing Membrane
Applied Physics Letters, 2011Co-Authors: Hyunjune Jang, Wonju ChoAbstract:High performance ion-sensitive field-effect transistors (ISFETs) were realized using silicon-on insulator substrate (SOI) and engineered Sensing Membrane. The engineered Sensing Membrane for the gate oxide was proposed to improve the chemical stability and obtain the enhanced output signal by stacking SiO2/HfO2/Al2O3 (OHA) layers. The SOI-metal–oxide–semiconductor field effect transistor (MOSFET) with the OHA gate oxide showed a high on/off current ratio of 1.8 × 1010 and a low subthreshold swing of 65 mV/dec. The SOI based ISFET with the OHA Membrane exhibited a low drift rate of 0.23 mV/h, a low hysteresis width of 1.85 mV, and a high pH sensitivity level of 57.1 mV/pH.
Fernando Catalina - One of the best experts on this subject based on the ideXlab platform.
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a switchable fluorescence solid sensor for hg2 detection in aqueous media based on a photocrosslinked Membrane functionalized with benzimidazolyl methyl piperazine derivative of 1 8 naphthalimide
Sensors and Actuators B-chemical, 2018Co-Authors: S Fernandezalonso, Teresa Corrales, Jesus L Pablos, Fernando CatalinaAbstract:Abstract A Selective fluorescence solid sensor for Hg2+ detection in aqueous solution (M-MBZN) has been developed by grafting N-(2-hydroxyethyl)-4-(4-(1H-benzo[d]imidazol-2-yl)methyl) piperazine-1-yl)-1,8-naphthalimide (MBZN) to a photo-crosslinked M-Cl Membrane reaction through the acid chloride groups. The resulting fluorescence sensor undergoes fluorescence enhancement upon binding mercuric ions which provokes a photo-induced electron transfer (PET) inhibition process from the piperazine to the naphthalimide moiety. Various photochemical parameters were determined by using pH-dependent absorption and fluorescence spectroscopies as well as the selective detection of Hg2+. The Sensing Membrane possesses a switchable “turn-on” fluorescence response to Hg2+ in pure water; it is easy to use and reusable and shows high selectivity and sensitivity.
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a switchable fluorescence solid sensor for hg2 detection in aqueous media based on a photocrosslinked Membrane functionalized with benzimidazolyl methyl piperazine derivative of 1 8 naphthalimide
Sensors and Actuators B-chemical, 2018Co-Authors: S Fernandezalonso, Teresa Corrales, Jesus L Pablos, Fernando CatalinaAbstract:Abstract A Selective fluorescence solid sensor for Hg2+ detection in aqueous solution (M-MBZN) has been developed by grafting N-(2-hydroxyethyl)-4-(4-(1H-benzo[d]imidazol-2-yl)methyl) piperazine-1-yl)-1,8-naphthalimide (MBZN) to a photo-crosslinked M-Cl Membrane reaction through the acid chloride groups. The resulting fluorescence sensor undergoes fluorescence enhancement upon binding mercuric ions which provokes a photo-induced electron transfer (PET) inhibition process from the piperazine to the naphthalimide moiety. Various photochemical parameters were determined by using pH-dependent absorption and fluorescence spectroscopies as well as the selective detection of Hg2+. The Sensing Membrane possesses a switchable “turn-on” fluorescence response to Hg2+ in pure water; it is easy to use and reusable and shows high selectivity and sensitivity.
Theresia Pursche - One of the best experts on this subject based on the ideXlab platform.
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spatiotemporal control of lipid conversion actin based mechanical forces and curvature sensors during clathrin ap 1 coated vesicle biogenesis
Cell Reports, 2017Co-Authors: Mihaela Anitei, Cornelia Czupalla, Christian Niehage, Christoph Stange, Kai Schuhmann, Pia Sala, Aleksander Czogalla, Theresia PurscheAbstract:Summary Clathrin/adaptor protein-1-coated carriers connect the secretory and the endocytic pathways. Carrier biogenesis relies on distinct protein networks changing Membrane shape at the trans -Golgi network, each regulating coat assembly, F-actin-based mechanical forces, or the biophysical properties of lipid bilayers. How these different hubs are spatiotemporally coordinated remains largely unknown. Using in vitro reconstitution systems, quantitative proteomics, and lipidomics, as well as in vivo cell-based assays, we characterize the protein networks controlling Membrane lipid composition, Membrane shape, and carrier scission. These include PIP5K1A and phospholipase C-beta 3 controlling the conversion of PI[4]P into diacylglycerol. PIP5K1A binding to RAC1 provides a link to F-actin-based mechanical forces needed to tubulate Membranes. Tubular Membranes then recruit the BAR-domain-containing arfaptin-1/2 guiding carrier scission. These findings provide a framework for synchronizing the chemical/biophysical properties of lipid bilayers, F-actin-based mechanical forces, and the activity of proteins Sensing Membrane shape during clathrin/adaptor protein-1-coated carrier biogenesis.
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Spatiotemporal Control of Lipid Conversion, Actin-Based Mechanical Forces, and Curvature Sensors during Clathrin/AP-1-Coated Vesicle Biogenesis
Cell reports, 2017Co-Authors: Mihaela Anitei, Cornelia Czupalla, Christian Niehage, Christoph Stange, Kai Schuhmann, Pia Sala, Aleksander Czogalla, Theresia Pursche, Ünal Coskun, Andrej ShevchenkoAbstract:Summary Clathrin/adaptor protein-1-coated carriers connect the secretory and the endocytic pathways. Carrier biogenesis relies on distinct protein networks changing Membrane shape at the trans -Golgi network, each regulating coat assembly, F-actin-based mechanical forces, or the biophysical properties of lipid bilayers. How these different hubs are spatiotemporally coordinated remains largely unknown. Using in vitro reconstitution systems, quantitative proteomics, and lipidomics, as well as in vivo cell-based assays, we characterize the protein networks controlling Membrane lipid composition, Membrane shape, and carrier scission. These include PIP5K1A and phospholipase C-beta 3 controlling the conversion of PI[4]P into diacylglycerol. PIP5K1A binding to RAC1 provides a link to F-actin-based mechanical forces needed to tubulate Membranes. Tubular Membranes then recruit the BAR-domain-containing arfaptin-1/2 guiding carrier scission. These findings provide a framework for synchronizing the chemical/biophysical properties of lipid bilayers, F-actin-based mechanical forces, and the activity of proteins Sensing Membrane shape during clathrin/adaptor protein-1-coated carrier biogenesis.
