Abstract: The present invention generally relates to methods for modulating the optical properties of a luminescent polymer via interaction with a species (e.g., an analyte). In some cases, the present invention provides methods for determination of an analyte by monitoring a change in an optical signal of a luminescent polymer upon exposure to an analyte. Methods of the present invention may be useful for the vapor phase detection of analytes such as explosives and toxins. The present invention also provides methods for increasing the luminescence intensity of a polymer, such as a polymer that has been photobleached, by exposing the luminescent polymer to a species such as a reducing agent.

Abstract: The present invention generally relates to compositions comprising at least one poly(thiophene) and an n-type material. The compositions can be used in a variety of applications, for example, in photovoltaic cells.

Abstract: The present invention relates to polymeric materials having enhanced properties. In some cases, the materials may comprise polymers having shape-persistent portions which may enhance the mechanical properties of the material. The materials may exhibit higher stiffness or strength and ductility values, resulting in higher energy absorption and enhanced protection, as well as longer lifetimes for product usage. In some cases, the materials may be optically transparent and lightweight, making them suitable for in various applications including protective materials.

Abstract: The present invention provides methods for performing dynamic nuclear polarization using biradicals with a structure of formula (I) as described herein. In general, the methods involve (a) providing a frozen sample in a magnetic field, wherein the frozen sample includes a biradical of formula (I) and an analyte with at least one spin half nucleus; (b) polarizing the at least one spin half nucleus of the analyte by irradiating the frozen sample with radiation having a frequency that excites electron spin transitions in the biradical; (c) optionally melting the sample to produce a molten sample; and (d) detecting nuclear spin transitions in the at least one spin half nucleus of the analyte in the frozen or molten sample. The present invention also provides biradicals with a structure of formula (I) with the proviso that Q1 and Q2 are different when X1 and X2 are —O—. The present invention also provides methods for making biradicals with a structure of formula (IA) as described herein.

Abstract: The present invention relates to a class of luminescent and conductive polymer compositions having chromophores, and particularly solid films of these compositions exhibiting increased luminescent lifetimes, quantum yields and amplified emissions. These desirable properties can be provided through polymers having rigid groups designed to prevent polymer reorganization, aggregation or ?-stacking upon solidification. These polymers can also display an unusually high stability with respect to solvent and heat exposures. The invention also relates to a sensor and a method for sensing an analyte through the luminescent and conductive properties of these polymers. Analytes can be sensed by activation of a chromophore at a polymer surface. Analytes include aromatics, phosphate ester groups and in particular explosives and chemical warfare agents in a gaseous state.

Abstract: The present invention provides compositions and devices comprising nanostructure networks, and related methods. The compositions may exhibit enhanced interaction between nanostructures, providing improved device performance (e.g., improved conductivity). In some embodiments, the devices are capable of interacting with various species to produce an observable signal from the device. In some cases, the compositions and devices may be useful in the determination of analytes, including—biological analytes (e.g., DNA, ebola virus, other infective agents, etc.), small, organic analytes, and the like. The embodiments described herein may exhibit high sensitivity and specificity to analytes and may be capable of analyte detection at femtomolar concentrations (e.g., 10 fM).

Abstract: The present invention generally relates to luminescent and/or optically absorbing compositions and/or precursors to those compositions, including solid films incorporating these compositions/precursors, exhibiting increased luminescent lifetimes, quantum yields, enhanced stabilities and/or amplified emissions. The present invention also relates to sensors and methods for sensing analytes through luminescent and/or optically absorbing properties of these compositions and/or precursors. Examples of analytes detectable by the invention include electrophiles, alkylating agents, thionyl halides, and phosphate ester groups including phosphoryl halides, cyanides and thioates such as those found in certain chemical warfare agents. The present invention additionally relates to devices and methods for amplifying emissions, such as those produced using the above-described compositions and/or precursors, by incorporating the composition and/or precursor within a polymer having an energy migration pathway.

Abstract: The present invention relates to a class of luminescent and conductive polymer compositions having chromophores, and particularly solid films of these compositions exhibiting increased luminescent lifetimes, quantum yields and amplified emissions. These desirable properties can be provided through polymers having rigid groups designed to prevent polymer reorganization, aggregation or ?-stacking upon solidification. These polymers can also display an unusually high stability with respect to solvent and heat exposures. The invention also relates to a sensor and a method for sensing an analyte through the luminescent and conductive properties of these polymers. Analytes can be sensed by activation of a chromophore at a polymer surface. Analytes include aromatics, phosphate ester groups and in particular explosives and chemical warfare agents in a gaseous state.

Abstract: The application generally describes devices, systems, and methods for determination of one or more analytes. Embodiments described herein may be useful as sensors for analytes such as explosives, chemical warfare agents, and/or toxins. In some cases, chemiresistor or chemFET sensor devices for monitoring volatile organics, especially chemical warfare agents such as sarin, are described. Some embodiments comprise functionalised carbon nanotube/conjugated polymer composites (6) as sensing material. In some embodiments, the polymer is poly(3-hexylthiophene), 3PHT, optionally substituted with calixarenes, or hexafluoroisopropanol susbstituted polythiophene, HFIP-PT. Biosensing embodiments are also described, as well as methods of manufacturing the devices.

Abstract: The present invention relates to devices, systems, and methods for determination of ionizing radiation. In some embodiments, the devices comprise nanocomposite materials containing nanostructures (e.g., carbon nanotubes) dispersed in radiation sensitive polymers. In some cases, the device may include a conductive pathway that may be affected upon exposure to ionizing radiation. Embodiments described herein may provide inexpensive, large area, low power, and highly sensitive radiation detection materials/devices.

Abstract: The synthesis of thiophene based conducting polymer molecular actuators, exhibiting electrically triggered molecular conformational transitions is reported. Actuation is believed to be the result of conformational rearrangement of the polymer backbone at the molecular level, not simply ion intercalation in the bulk polymer chain upon electrochemical activation. Molecular actuation results from ?-? stacking of thiophene oligomers upon oxidation, producing a reversible molecular displacement that leads to surprising material properties, such as electrically controllable porosity and large strains. The existence of active molecular conformational changes is supported by in situ electrochemical data. Single molecule techniques have been used to characterize the molecular actuators.

Abstract: The present invention provides sensors and methods for determination of an analyte. The analytes may be determined by monitoring, for example, a change in an optical signal of an emissive material upon exposure to an analyte. In some embodiments, the analyte and the emissive material may interact via a chemical reaction, or other chemical, biochemical or biological interaction (e.g., recognition), to form a new emissive species. In some cases, the present invention may be used for the detection of analytes such as explosives (e.g., RDX, PETN). Methods of the present invention may be advantageous in that the high sensitivity of luminescence (e.g., fluorescence) spectroscopy can allow for the reliable detection of small changes in luminescence intensity.

Abstract: The present invention generally relates to polymers with lasing characteristics that allow the polymers to be useful in detecting analytes. In one aspect, the polymer, upon an interaction with an analyte, may exhibit a change in a lasing characteristic that can be determined in some fashion. For example, interaction of an analyte with the polymer may affect the ability of the polymer to reach an excited state that allows stimulated emission of photons to occur, which may be determined, thereby determining the analyte. In another aspect, the polymer, upon interaction with an analyte, may exhibit a change in stimulated emission that is at least 10 times greater with respect to a change in the spontaneous emission of the polymer upon interaction with the analyte. The polymer may be a conjugated polymer in some cases. In one set of embodiments, the polymer includes one or more hydrocarbon side chains, which may be parallel to the polymer backbone in some instances.

Abstract: The present invention provides sensors and methods for determination of an analyte. The analytes may be determined by monitoring, for example, a change in an optical signal of an emissive material upon exposure to an analyte. In some embodiments, the analyte and the emissive material may interact via a chemical reaction, or other chemical, biochemical or biological interaction (e.g., recognition), to form a new emissive species. In some cases, the present invention may be used for the detection of analytes such as explosives (e.g., RDX, PETN). Methods of the present invention may be advantageous in that the high sensitivity of luminescence (e.g., fluorescence) spectroscopy can allow for the reliable detection of small changes in luminescence intensity.

Abstract: The present invention provides a series of systems, devices, and methods relating to the determination of explosives, such as peroxides or peroxide precursors, and other species. Embodiments of the invention may allow a sample suspected of containing an explosive (e.g., a peroxide) or other species to interact with a reactant, wherein the sample may react and cause light emission from the reactant. Advantages of the present invention may include the simplification of devices for determination of peroxide-based explosives, wherein the devices are portable and, in some cases, disposable. Other advantages may include relative ease of fabrication and operation.

Abstract: The present invention relates to a class of luminescent and conductive polymer compositions having chromophores, and particularly solid films of these compositions exhibiting increased luminescent lifetimes, quantum yields and amplified emissions. These desirable properties can be provided through polymers having rigid groups designed to prevent polymer reorganization, aggregation or ?-stacking upon solidification. These polymers can also display an unusually high stability with respect to solvent and heat exposures. The invention also relates to a sensor and a method for sensing an analyte through the luminescent and conductive properties of these polymers. Analytes can be sensed by activation of a chromophore at a polymer surface. Analytes include aromatics, phosphate ester groups and in particular explosives and chemical warfare agents in a gaseous state.

Abstract: The present invention generally relates to polymers with lasing characteristics that allow the polymers to be useful in detecting analytes. In one aspect, the polymer, upon an interaction with an analyte, may exhibit a change in a lasing characteristic that can be determined in some fashion. For example, interaction of an analyte with the polymer may affect the ability of the polymer to reach an excited state that allows stimulated emission of photons to occur, which may be determined, thereby determining the analyte. In another aspect, the polymer, upon interaction with an analyte, may exhibit a change in stimulated emission that is at least 10 times greater with respect to a change in the spontaneous emission of the polymer upon interaction with the analyte. The polymer may be a conjugated polymer in some cases. In one set of embodiments, the polymer includes one or more hydrocarbon side chains, which may be parallel to the polymer backbone in some instances.

Abstract: The present invention generally provides compositions including carbon-based nanostructures, catalyst materials and systems, and related methods. In some cases, the present invention relates to carbon-based nanostructures comprising a high density of charged moieties. Methods of the invention may provide the ability to introduce a wide range of charged moieties to carbon-based nanostructures. The present invention may provide a facile and modular approach to synthesizing molecules that may be useful in various applications including sensors, catalysts, and electrodes.

Abstract: The present invention generally relates to methods for modulating the optical properties of a luminescent polymer via interaction with a species (e.g., an analyte). In some cases, the present invention provides methods for determination of an analyte by monitoring a change in an optical signal of a luminescent polymer upon exposure to an analyte. Methods of the present invention may be useful for the vapor phase detection of analytes such as explosives and toxins. The present invention also provides methods for increasing the luminescence intensity of a polymer, such as a polymer that has been photobleached, by exposing the luminescent polymer to a species such as a reducing agent.

Abstract: The present invention relates to fluorescent, semiconductive polymers comprising electron withdrawing groups bonded to the polymer. The invention also relates to a method of detecting analytes comprising contacting the analyte with the fluorescent, semiconductive polymers of the present invention. The invention also relates to light emitting devices, photovoltaic devices, and sensors comprising the fluorescent, semiconductive polymers of the present invention.