Abstract: A method and sensing system for the determination per and poly-fluoroalkyl substances (PFASs) is disclosed, wherein the probe is based on measurement of the redox activity of a redox indicator. The method includes adding a PFAS compound to an indicator solution, gel, 3D printed object, electrode or a sensing surface containing and measuring the change in the indicator signal as a function of PFAS concentration. Further provided is a portable sensor for rapid monitoring of the presence and PFAS concentrations. The present invention includes deposition of the indicator component within a method, assay, apparatus and sensing platform. Further provided is a composite electrode and sensor with binding and signaling activity for a broad range of PFAS, as well as printing ink compositions that incorporate the redox indicator.

Abstract: Methods and assay for the portable colorimetric detection of an antioxidant in a food sample. The method includes the steps of providing a colorimetric reagent, the reagent including a plurality of ceria nanoparticles immobilized to a support, contacting the colorimetric reagent with the food sample, and detecting an optical property of the colorimetric reagent, where a change in the optical property of the colorimetric reagent is associated with the presence of antioxidant in the food sample. The change in the optical property of the colorimetric reagent is dependent upon the concentration of the antioxidant in the food sample.

Abstract: A colorimetric reagent in the form of nanoparticles, composite nanoparticles, and nanoparticle coatings, including methods of use, methods of preparation, deposition, and assembly of related devices and specific applications. The colorimetric reagent comprises cerium oxide nanoparticles which are used in solution or immobilized on a solid support, either alone or in conjunction with oxidase enzymes, to form an active colorimetric component that reacts with an analyte to form a colored complex. The rate of color change and the intensity of the color are proportional to the amount of analyte present in the sample. Also described is the use of ceria and doped ceria nanoparticles as an oxygen storage/delivery vehicle for oxidase enzymes and applications in biocatalytic processes in anaerobic conditions of interest in biomedicine and bioanalysis.

Abstract: The present invention provides a method for forming compositions having a plurality of ultra-fine metallic particles, and the metallic composition produced therewith. Also provided is a substrate coated with the plurality of ultra-fine metallic particles obtained in accordance with the method of the present invention.

Abstract: Methods and assay for the portable colorimetric detection of an antioxidant in a food sample. According to one aspect the method comprises the steps of providing a colorimetric reagent comprising a plurality of ceria nanoparticles immobilized to a support, contacting the colorimetric reagent with the food sample, and detecting an optical property of the colorimetric reagent, wherein a change in the optical property of the colorimetric reagent is associated with the presence of antioxidant in the food sample, and further wherein the change in the optical property of the colorimetric reagent is dependent upon the concentration of the antioxidant in said food sample.

Abstract: A colorimetric reagent in the form of nanoparticles, composite nanoparticles, and nanoparticle coatings, including methods of use, methods of preparation, deposition, and assembly of related devices and specific applications. The colorimetric reagent comprises cerium oxide nanoparticles which are used in solution or immobilized on a solid support, either alone or in conjunction with oxidase enzymes, to form an active colorimetric component that reacts with an analyte to form a colored complex. The rate of color change and the intensity of the color are proportional to the amount of analyte present in the sample. Also described is the use of ceria and doped ceria nanoparticles as an oxygen storage/delivery vehicle for oxidase enzymes and applications in biocatalytic processes in anaerobic conditions of interest in biomedicine and bioanalysis.

Abstract: The present invention provides a method for forming compositions having a plurality of ultra-fine metallic particles, and the metallic composition produced therewith. Also provided is a substrate coated with the plurality of ultra-fine metallic particles obtained in accordance with the method of the present invention.

Abstract: A colorimetric reagent in the form of nanoparticles, composite nanoparticles, and nanoparticle coatings, including methods of use, methods of preparation, deposition, and assembly of related devices and specific applications. The colorimetric reagent comprises cerium oxide nanoparticles which are used in solution or immobilized on a solid support, either alone or in conjunction with oxidase enzymes, to form an active colorimetric component that reacts with an analyte to form a colored complex. The rate of color change and the intensity of the color are proportional to the amount of analyte present in the sample. Also described is the use of ceria and doped ceria nanoparticles as an oxygen storage/delivery vehicle for oxidase enzymes and applications in biocatalytic processes in anaerobic conditions of interest in biomedicine and bioanalysis.

Abstract: The invention provides monodisperse ultra-fine metallic particles having a low degree of agglomeration and a high degree of crystallinity and oxidation resistance, and methods for forming such particles. The invention provides a method of controlling the size and size distribution of ultra-fine metal particles by regulating the pH of a polyol-type process. The methods of the invention make it possible to increase the metal loading in a polyol-type process without increasing particle size, enabling the production of ultra-fine metallic particles in high yield.

Abstract: The present invention provides a method for forming compositions having a plurality of ultra-fine metallic particles, and the metallic composition produced therewith. Also provided is a substrate coated with the plurality of ultra-fine metallic particles obtained in accordance with the method of the present invention.

Abstract: The present invention provides a method for forming compositions having a plurality of ultra-fine metallic particles, and the metallic composition produced therewith. Also provided is a substrate coated with the plurality of ultra-fine metallic particles obtained in accordance with the method of the present invention.

Abstract: The present invention provides a metallic composition, which contains a plurality of ultra-fine metallic particles (e.g., ultra-fine copper, nickel, or silver particles) having at least one desirable feature, such as, tight size distribution, low degree of agglomeration, and high degree of crystallinity and oxidation resistance. The present invention further provides a method for forming the ultra-fine metallic particles. Also provided are a substance or substrate coated with the ultra-fine metallic particles and a method of coating a substance or substrate with the ultra-fine metallic particles. Furthermore, the present invention provides a method of controlling the size of ultra-fine metal particles formed in a reducing reaction in a liquid. Also provided is a method for producing ultra-fine metallic particles, which utilizes a concentrated reaction system.

Abstract: The present invention provides a metallic composition, which contains a plurality of ultra-fine metallic particles (e.g., ultra-fine copper, nickel, or silver particles) having at least one desirable feature, such as, tight size distribution, low degree of agglomeration, and high degree of crystallinity and oxidation resistance. The present invention further provides a method for forming the ultra-fine metallic particles. Also provided are a substance or substrate coated with the ultra-fine metallic particles and a method of coating a substance or substrate with the ultra-fine metallic particles. Furthermore, the present invention provides a method of controlling the size of ultra-fine metal particles formed in a reducing reaction in a liquid. Also provided is a method for producing ultra-fine metallic particles, which utilizes a concentrated reaction system.

Abstract: The present invention provides a method for forming compositions having a plurality of ultra-fine metallic particles, and the metallic composition produced therewith. Also provided is a substrate coated with the plurality of ultra-fine metallic particles obtained in accordance with the method of the present invention.

Abstract: The present invention provides a metallic composition, which contains a plurality of ultra-fine metallic particles (e.g., ultra-fine copper, nickel, or silver particles) having at least one desirable feature, such as, tight size distribution, low degree of agglomeration, and high degree of crystallinity and oxidation resistance. The present invention further provides a method for forming the ultra-fine metallic particles. Also provided are a substance or substrate coated with the ultra-fine metallic particles and a method of coating a substance or substrate with the ultra-fine metallic particles. Furthermore, the present invention provides a method of controlling the size of ultra-fine metal particles formed in a reducing reaction in a liquid. Also provided is a method for producing ultra-fine metallic particles, which utilizes a concentrated reaction system.

Abstract: The present invention provides a metallic composition, which contains a plurality of ultra-fine metallic particles (e.g., ultra-fine copper, nickel, or silver particles) having at least one desirable feature, such as, tight size distribution, low degree of agglomeration, and high degree of crystallinity and oxidation resistance. The present invention further provides a method for forming the ultra-fine metallic particles. Also provided are a substance or substrate coated with the ultra-fine metallic particles and a method of coating a substance or substrate with the ultra-fine metallic particles. Furthermore, the present invention provides a method of controlling the size of ultra-fine metal particles formed in a reducing reaction in a liquid. Also provided is a method for producing ultra-fine metallic particles, which utilizes a concentrated reaction system.