Abstract: A belt wearable by a human subject includes a variety of sensors that collect information about the wearer, the wearer's environment, and the wearer's movements. A communication interface on the belt allows sensor data collected by the belt to be transferred to a storage server. In some examples, the communication interface is a Wi-Fi interface, a cellular interface, or a removable memory interface. The data is processed to identify activities performed by the wearer such as walking, driving, and working at heights. In some examples, events such as aggressive driving events, slips and falls, and unsafe lifting are detected. In some examples, this information is used to generate reports that allow an employer to manage the productivity and safety of a workforce.

Abstract: Pressure/strain piezoresistive are described that include a poled piezoelectric polymer such as PVDF or P(VDF-TrFE) and graphene. The poled piezoelectric polymer and the graphene are electronically coupled to form a heterojunction and provide an ultra-high sensitivity pressure/strain sensor. The sensors can be carried on a flexible supporting substrate such as PDMS or PET to exhibit high flexibility. The materials of formation can be biocompatible and the sensors can be wearable or implantable.

Abstract: A graphene-based ion sensitive field effect transistor (GISFET) with high sensitivity and selectivity for ions is provided. For example, the GISFET of the present invention can exhibit high sensitivity and selectivity for K+ ions has been demonstrated utilizing a valinomycin-based ion selective membrane. The sensitivity of the GISFET can be at least about 50 millivolts/decade and can be stable for a time period of about two months, indicating the GISFET's reliability and effectiveness for physiological monitoring.

Abstract: The invention relates to a micro cantilever beam sensor and making method, including a chip, and its character: there is at least a group of sensor cells set on the chip, where the sensor cell is composed of the completely same four force-sensitive resistors composing a Wheatstone bridge and two cantilever beams, two of these resistors are on the substrate of the chip, the other two are on the two cantilever beams, respectively, one cantilever beam acts on a measuring cantilever beam and the other one acts on a reference cantilever beam, and the measuring cantilever beam is set with a sensitive layer on the surface. It can design and prepare in a liquid-flow micro-tank by front etching and silicon-glass bonding techniques, to directly detect liquid biomolecule. Whether applied to gas sensor or biosensor, it will play an important role in reducing device size, enhancing device sensitivity and realizing sensor multi-functionality.

Abstract: Pressure/strain piezoresistive are described that include a poled piezoelectric polymer such as PVDF or P(VDF-TrFE) and graphene. The poled piezoelectric polymer and the graphene are electronically coupled to form a heterojunction and provide an ultra-high sensitivity pressure/strain sensor. The sensors can be carried on a flexible supporting substrate such as PDMS or PET to exhibit high flexibility. The materials of formation can be biocompatible and the sensors can be wearable or implantable.

Abstract: Methods of synthesis and fabrication of a transition metal dichalcogenide (TMD) structures are disclosed. A method can include first patterning a transition metal (TM) on a substrate and placing the substrate in a process chamber. Oxygen can be applied to the transition metal on the substrate and a mixture of highly reactive transition metal oxides can be formed and simultaneously thinned down by sublimation. Finally, a chalcogen can be applied to the substrate and a transition metal dichalcogenide structure can be formed.

Abstract: A belt wearable by a human subject includes a variety of sensors that collect information about the wearer, the wearer's environment, and the wearer's movements. A communication interface on the belt allows sensor data collected by the belt to be transferred to a storage server. In some examples, the communication interface is a Wi-Fi interface, a cellular interface, or a removable memory interface. The data is processed to identify activities performed by the wearer such as walking, driving, and working at heights. In some examples, events such as aggressive driving events, slips and falls, and unsafe lifting are detected. In some examples, this information is used to generate reports that allow an employer to manage the productivity and safety of a workforce.

Abstract: A graphene-based ion sensitive field effect transistor (GISFET) with high sensitivity and selectivity for ions is provided. For example, the GISFET of the present invention can exhibit high sensitivity and selectivity for K+ ions has been demonstrated utilizing a valinomycin-based ion selective membrane. The sensitivity of the GISFET can be at least about 50 millivolts/decade and can be stable for a time period of about two months, indicating the GISFET's reliability and effectiveness for physiological monitoring.

Abstract: The invention relates to a micro cantilever beam sensor and making method, including a chip, and its character: there is at least a group of sensor cells set on the chip, where the sensor cell is composed of the completely same four force-sensitive resistors composing a Wheatstone bridge and two cantilever beams, two of these resistors are on the substrate of the chip, the other two are on the two cantilever beams, respectively, one cantilever beam acts on a measuring cantilever beam and the other one acts on a reference cantilever beam, and the measuring cantilever beam is set with a sensitive layer on the surface. It can design and prepare in a liquid-flow micro-tank by front etching and silicon-glass bonding techniques, to directly detect liquid biomolecule. Whether applied to gas sensor or biosensor, it will play an important role in reducing device size, enhancing device sensitivity and realizing sensor multi-functionality.

Abstract: A microcantilever based photoacoustic sensor is generally provided. In one embodiment, the microcantilever includes: a substrate; a GaN layer on the substrate, wherein the GaN layer defines a cantilever extending beyond an edge of the substrate, with a base area of the cantilever defined by the area spanning the edge of the substrate; a heterojunction field effect transistor (HFET) deflection transducer positioned on the cantilever; a pair of electrical contacts, each electrically connected to the HFET deflection transducer; and a microfluidic channel in fluid communication with an analyte reservoir, wherein the analyte reservoir is positioned at the base of the cantilever. A sensing system is also generally provided.

Abstract: Microcantilevers and systems incorporating the microcantilevers are described that can be utilized to perform selective detection of VOCs. The systems can detect VOCs at temperatures below the auto-ignition temperature of the VOCs and the microcantilevers need not be functionalized with any reactive groups particularly designed for the VOCs to be detected. The microcantilevers are triangular microcantilevers that can be formed of high bandgap semiconductors such as AlGaN/GaN heterojunction semiconductors.

Abstract: Methods of synthesis and fabrication of a transition metal dichalcogenide (TMD) structures are disclosed. A method can include first patterning a transition metal (TM) on a substrate and placing the substrate in a process chamber. Oxygen can be applied to the transition metal on the substrate and a mixture of highly reactive transition metal oxides can be formed and simultaneously thinned down by sublimation. Finally, a chalcogen can be applied to the substrate and a transition metal dichalcogenide structure can be formed.

Abstract: Microcantilevers and systems incorporating the microcantilevers are described that can be utilized to perform selective detection of VOCs. The systems can detect VOCs at temperatures below the auto-ignition temperature of the VOCs and the microcantilevers need not be functionalized with any reactive groups particularly designed for the VOCs to be detected. The microcantilevers are triangular microcantilevers that can be formed of high bandgap semiconductors such as AlGaN/GaN heterojunction semiconductors.

Abstract: A microcantilever based photoacoustic sensor is generally provided. In one embodiment, the microcantilever includes: a substrate; a GaN layer on the substrate, wherein the GaN layer defines a cantilever extending beyond an edge of the substrate, with a base area of the cantilever defined by the area spanning the edge of the substrate; a HFET deflection transducer positioned on the cantilever; a pair of electrical contacts, each electrically connected to the HFET deflection transducer; and a microfluidic channel in fluid communication with an analyte reservoir, wherein the analyte reservoir is positioned at the base of the cantilever. A sensing system is also generally provided.

Abstract: Sensor are generally provided that include a layer of silicon oxide on a portion of a n+ layer to form an uneven surface where the layer of silicon oxide defines a thicker region than an exposed portion of the n+ layer. First and second metal contacts can be on the layer of silicon oxide, with first and second nanowires extending respectively from a first base on the first metal contact and a second base on the second metal contact. The first nanowire and the second nanowire are connected together at an apex to form a v-shaped nanocantilever, wherein the apex is positioned over the exposed n+ layer, and wherein the nanowires comprise indium and nitrogen. Methods of fabricating such sensors, along with methods of their use, are also generally provided.

Abstract: Methods and systems of detecting analytes using a microcantilever system are generally described. The microcantilever system generally includes micro- or nano-sized elements that can be electrostatically driven to resonance. Utilizing the disclosed devices and methods, direct electronic detection of the resonant frequency, changes of the resonant frequency, and associated phase signal of a micro- or nano-sized element can be utilized to measure the presence of a targeted analyte. The detection system of the present invention utilizes a non-contact microcantilever device. That is, the surface of the microcantilever (e.g., the surface of the resonating beam) does not bond or otherwise attach to an analyte or other chemical. Thus, the microcantilever device, including the resonating beam, can be kept in pristine condition during and even after repeated use.

Abstract: Sensor are generally provided that include a layer of silicon oxide on a portion of a n+ layer to form an uneven surface where the layer of silicon oxide defines a thicker region than an exposed portion of the n+ layer. First and second metal contacts can be on the layer of silicon oxide, with first and second nanowires extending respectively from a first base on the first metal contact and a second base on the second metal contact. The first nanowire and the second nanowire are connected together at an apex to form a v-shaped nanocantilever, wherein the apex is positioned over the exposed n+ layer, and wherein the nanowires comprise indium and nitrogen. Methods of fabricating such sensors, along with methods of their use, are also generally provided.

Abstract: Methods and systems of detecting analytes using a microcantilever system are generally described. The microcantilever system generally includes micro- or nano-sized elements that can be electrostatically driven to resonance. Utilizing the disclosed devices and methods, direct electronic detection of the resonant frequency, changes of the resonant frequency, and associated phase signal of a micro- or nano-sized element can be utilized to measure the presence of a targeted analyte. The detection system of the present invention utilizes a non-contact microcantilever device. That is, the surface of the microcantilever (e.g., the surface of the resonating beam) does not bond or otherwise attach to an analyte or other chemical. Thus, the microcantilever device, including the resonating beam, can be kept in pristine condition during and even after repeated use.