Abstract: The invention encompasses hydrogels, monomer precursors of the hydrogels, methods for the preparation thereof, and methods of use therefor. The linking of monomers can take place using non-radical, bioorthogonal reactions such as copper-free click-chemistry.

Abstract: The invention provides a method for preparing an expanded cell or tissue sample suitable for microscopic analysis. Expanding the sample can be achieved by binding, e.g., anchoring, key biomolecules to a DMAA-TF polymer network and swelling, or expanding, the polymer network, thereby moving the biomolecules apart as further described herein. As the biomolecules are anchored to the polymer network isotropic expansion of the polymer network retains the spatial orientation of the biomolecules resulting in an expanded, or enlarged, sample.

Abstract: The invention encompasses hydrogels, monomer precursors of the hydrogels, methods for the preparation thereof, and methods of use therefor. The linking of monomers can take place using non-radical, bioorthogonal reactions such as copper-free click-chemistry.

Abstract: The invention encompasses hydrogels, monomer precursors of the hydrogels, methods for the preparation thereof, and methods of use therefor. The linking of monomers can take place using non-radical, bioorthogonal reactions such as copper-free click-chemistry.

Abstract: A method for synthesizing nanoparticles by sonofragmentation includes dispersing ultra-thin substrate units in a solvent chosen for suitability for sonofragmentation of the substrate, forming a suspension; ultrasonicating the suspension for a length of time sufficient to fragment the substrate into nanoparticles that are dispersed in the solvent; and evaporating the solvent. Solvent exchange with a second solvent may be performed. The synthesized nanoparticles are highly crystalline and monodispersed. The surface of the synthesized nanoparticles may be functionalized by choosing the solvents according to chemistry related to the intended surface functionalization of the synthesized nanoparticles, by adding surfactants to one or more of the solvents, and/or by performing ligand exchange or chemical modification to replace surface-bonded solvent or surfactant molecules with other functional groups to produce nanoparticles having the desired surface functionalization.

Abstract: The present invention enables three-dimensional nanofabrication by isotropic shrinking of patterned hydrogels. A hydrogel is first expanded, the rate of expansion being controlled by the concentration of the crosslinker. The hydrogel is then infused with a reactive group and patterned in three dimensions using a photon beam through a limited-diffraction microscope. Functional particles or materials are then deposited on the pattern. The hydrogel is then shrunk and cleaved from the pattern.

Abstract: The invention provides a method for preparing an expanded cell or tissue sample suitable for microscopic analysis. Expanding the sample can be achieved by binding, e.g., anchoring, key biomolecules to a DMAA-TF polymer network and swelling, or expanding, the polymer network, thereby moving the biomolecules apart as further described herein. As the biomolecules are anchored to the polymer network isotropic expansion of the polymer network retains the spatial orientation of the biomolecules resulting in an expanded, or enlarged, sample.

Abstract: The present invention generally relates to nanoscale wires, and to methods of producing nanoscale wires. In some aspects, the nanoscale wires are nanowires comprising a core which is continuous and a shell which may be continuous or discontinuous, and/or may have regions having different cross-sectional areas. In some embodiments, the shell regions are produced by passing the shell material (or a precursor thereof) over a core nanoscale wire under conditions in which Plateau-Raleigh crystal growth occurs, which can lead to non-homogenous deposition of the shell material on different regions of the core. The core and the shell each independently may comprise semiconductors, and/or non-semiconductor materials such as semiconductor oxides, metals, polymers, or the like. Other embodiments are generally directed to systems and methods of making or using such nanoscale wires, devices containing such nanoscale wires, or the like.

Abstract: The invention encompasses hydrogels, monomer precursors of the hydrogels, methods for the preparation thereof, and methods of use therefor. The linking of monomers can take place using non-radical, bioorthogonal reactions such as copper-free click-chemistry.

Abstract: The present invention generally relates to nanoscale wires and, in particular, to nanoscale wires with heterojunctions, such as tip-localized homo- or heterojunctions. In one aspect, the nanoscale wire may include a core, an inner shell surrounding the core, and an outer shell surrounding the inner shell. The outer shell may also contact the core, e.g., at an end portion of the nanoscale wire. In some cases, such nanoscale wires may be used as electrical devices. For example a p-n junction may be created where the inner shell is electrically insulating, and the core and the outer shell are p-doped and n-doped. Other aspects of the present invention generally relate to methods of making or using such nanoscale wires, devices, or kits including such nanoscale wires, or the like.

Abstract: A method for synthesizing nanoparticles by sonofragmentation includes dispersing ultra-thin substrate units in a solvent chosen for suitability for sonofragmentation of the substrate, forming a suspension; ultrasonicating the suspension for a length of time sufficient to fragment the substrate into nanoparticles that are dispersed in the solvent; and evaporating the solvent. Solvent exchange with a second solvent may be performed. The synthesized nanoparticles are highly crystalline and monodispersed. The surface of the synthesized nanoparticles may be functionalized by choosing the solvents according to chemistry related to the intended surface functionalization of the synthesized nanoparticles, by adding surfactants to one or more of the solvents, and/or by performing ligand exchange or chemical modification to replace surface-bonded solvent or surfactant molecules with other functional groups to produce nanoparticles having the desired surface functionalization.

Abstract: The present invention generally relates to nanoscale wires for use in sensors and other applications. In various embodiments, a probe comprising a nanotube (or other nanoscale wire) is provided that can be directly inserted into a cell to determine a property of the cell, e.g., an electrical property. In some cases, only the tip of the nanoscale wire is inserted into the cell; this tip may be very small relative to the cell, allowing for very precise study. In some aspects, the tip of the probe is held by a holding member positioned on a substrate, e.g., at an angle, which makes it easier for the probe to be inserted into the cell. The nanoscale wire may also be connected to electrodes and/or form part of a transistor, such that a property of the nanoscale wire, and thus of the cell, may be determined. Such probes may also be useful for studying other samples besides cells.

Abstract: The present invention generally relates to nanoscale wires, and to systems and methods of producing nanoscale wires. In some aspects, the present invention is generally related to facet-specific deposition on semiconductor surfaces. In one embodiment, a first surface of a nanoscale wire, or a semiconductor, is preferentially oxidized relative to a second surface, and material is preferentially deposited on the second surface relative to the first surface. For example, the nanoscale wire or semiconductor may be a silicon nanowire that is initially exposed to an etchant to remove silicon oxide, then exposed to an oxidant under conditions such that one facet or surface (e.g., a {113} facet) is oxidized more quickly than another facet or surface (e.g., a {111} facet). Material may then be deposited or immobilized on the less-oxidized facet relative to the more-oxidized facet.

Abstract: The present invention enables three-dimensional nanofabrication by isotropic shrinking of patterned hydrogels. A hydrogel is first expanded, the rate of expansion being controlled by the concentration of the crosslinker. The hydrogel is then infused with a reactive group and patterned in three dimensions using a photon beam through a limited-diffraction microscope. Functional particles or materials are then deposited on the pattern. The hydrogel is then shrunk and cleaved from the pattern.

Abstract: The present invention generally relates to nanoscale wires, and to methods of producing nanoscale wires. In some aspects, the nanoscale wires are nanowires comprising a core which is continuous and a shell which may be continuous or discontinuous, and/or may have regions having different cross-sectional areas. In some embodiments, the shell regions are produced by passing the shell material (or a precursor thereof) over a core nanoscale wire under conditions in which Plateau-Raleigh crystal growth occurs, which can lead to non-homogenous deposition of the shell material on different regions of the core. The core and the shell each independently may comprise semiconductors, and/or non-semiconductor materials such as semiconductor oxides, metals, polymers, or the like. Other embodiments are generally directed to systems and methods of making or using such nanoscale wires, devices containing such nanoscale wires, or the like.

Abstract: The present invention generally relates to nanotechnology, including field effect transistors and other devices used as sensors (for example, for electrophysiological studies), nanotube structures, and applications. Certain aspects of the present invention are generally directed to transistors such as field effect transistors, and other similar devices. In one set of embodiments, a field effect transistor is used where a nanoscale wire, for example, a silicon nanowire, acts as a transistor channel connecting a source electrode to a drain electrode. In some cases, a portion of the transistor channel is exposed to an environment that is to be determined, for example, the interior or cytosol of a cell. A nanotube or other suitable fluidic channel may be extended from the transistor channel into a suitable environment, such as a contained environment within a cell, so that the environment is in electrical communication with the transistor channel via the fluidic channel.

Abstract: The present invention generally relates to nanoscale wires and, in particular, to probes comprising nanoscale wires for use in determining electrical and/or chemical properties in a tissue or other material. For example, in certain embodiments, a probe comprising nanoscale wires may be inserted into an electrically-active tissue, such as the heart or the brain, and the nanoscale wires may be used to determine electrical properties of the tissue, e.g., action potentials or other electrical activity. In addition, in some embodiments, a nanoscale wire may be modified to determine chemical properties of a tissue. A probe comprising such nanoscale wires can be inserted into a tissue (not necessarily electrically active) to determine various properties, e.g., chemical or mechanical properties. In addition, in some embodiments, a probe is provided that can be used to stimulate tissues, e.g., by providing electrical stimuli via one or more nanoscale wires.

Abstract: The present invention generally relates to nanoscale wires for use in sensors and other applications. In various embodiments, a probe comprising a nanotube (or other nanoscale wire) is provided that can be directly inserted into a cell to determine a property of the cell, e.g., an electrical property. In some cases, only the tip of the nanoscale wire is inserted into the cell; this tip may be very small relative to the cell, allowing for very precise study. In some aspects, the tip of the probe is held by a holding member positioned on a substrate, e.g., at an angle, which makes it easier for the probe to be inserted into the cell. The nanoscale wire may also be connected to electrodes and/or form part of a transistor, such that a property of the nanoscale wire, and thus of the cell, may be determined. Such probes may also be useful for studying other samples besides cells.

Abstract: The present invention generally relates to nanotechnology, including field effect transistors and other devices used as sensors (for example, for electrophysiological studies), nanotube structures, and applications. Certain aspects of the present invention are generally directed to transistors such as field effect transistors, and other similar devices. In one set of embodiments, a field effect transistor is used where a nanoscale wire, for example, a silicon nanowire, acts as a transistor channel connecting a source electrode to a drain electrode. In some cases, a portion of the transistor channel is exposed to an environment that is to be determined, for example, the interior or cytosol of a cell. A nanotube or other suitable fluidic channel may be extended from the transistor channel into a suitable environment, such as a contained environment within a cell, so that the environment is in electrical communication with the transistor channel via the fluidic channel.