The present invention relates to an interdigitated microelectrode biosensor using the reaction between receptors and target biomaterials, the interdigitated microelectrode biosensor comprising: an insulating layer formed so as to cover all of the sensor formation area of a substrate; a first interdigitated microelectrode formed such that a plurality of first protruding electrodes are arranged in a comb shape on the insulating layer of the substrate; a second interdigitated microelectrode, facing the first interdigitated microelectrode and formed such that a plurality of second protruding electrodes are arranged in a comb shape on the insulating layer of the substrate such that the plurality of second protruding electrodes are arranged to respectively interdigitate with the plurality of first protruding electrodes formed at the first interdigitated microelectrode; and a plurality of receptors arranged in the space between the first and second interdigitated microelectrodes, which are arranged to interdigitate with each other, so as to specifically react with the target biomaterial, thereby increasing an impedance detection width and detection limit, and improving detection accuracy according to the characteristics of each monomer and each polymer.

The present invention relates to an interdigitated microelectrode biosensor using the reaction between receptors and target biomaterials, the interdigitated microelectrode biosensor comprising: an insulating layer formed so as to cover all of the sensor formation area of a substrate; a first interdigitated microelectrode formed such that a plurality of first protruding electrodes are arranged in a comb shape on the insulating layer of the substrate; a second interdigitated microelectrode, facing the first interdigitated microelectrode and formed such that a plurality of second protruding electrodes are arranged in a comb shape on the insulating layer of the substrate such that the plurality of second protruding electrodes are arranged to respectively interdigitate with the plurality of first protruding electrodes formed at the first interdigitated microelectrode; and a plurality of receptors arranged in the space between the first and second interdigitated microelectrodes, which are arranged to interdigitate with each other, so as to specifically react with the target biomaterial, thereby increasing an impedance detection width and detection limit, and improving detection accuracy according to the characteristics of each monomer and each polymer.

Carbon-based materials, and associated methods and articles, are generally provided. In some embodiments, a carbon-based material comprises a carbon-based portion and a functional group bonded to the carbon-based portion. The functional group may be capable of forming a reversible covalent bond with a species. Carbon may make up greater than or equal to 30 wt % of the carbon-based portion. The carbon-based portion may comprise graphene, and a ratio of a total number of functional groups in a plurality of functional groups bonded to the graphene to a total number of carbon atoms in the plurality of carbon atoms of the graphene may be greater than or equal to 1:50. The carbon-based portion may comprise graphene, and greater than or equal to 70% of the graphene sheets may be spaced apart from their nearest neighbors by a distance of greater than or equal to 10 Å. A method may comprise applying a voltage to a carbon-based material. The voltage may be applied in the presence of a combination of solvents comprising a dissolved species. The combination of solvents may comprise a solvent stable at voltages of greater than or equal to −3.15 V and less than or equal to −2.2 V and/or may comprise a solvent with a surface tension within 25% of a surface tension of the carbon-based material. The voltage may be a decreasing voltage that decreases at a rate of greater than or equal to 2 μV/s and less than or equal to 40 μV/s and has a value of greater than or equal to −2.2 V and less than or equal to −3.15 V at at least one point in time.

Methods and devices for quantifying creatinine in a test sample are provided. The test sample is contacted with a sensing composition to obtain a product comprising a hydantoin-transition metal complex and ammonia. The sensing composition comprises creatinine deaminase and a transition metal salt. The creatinine deaminase enzymatically reacts with creatinine to provide the N-methyl hydantoin and ammonia. The N-methyl hydantoin forms the hydantoin-transition metal complex with the transition salt. A potential difference is applied to the product to measure a current signal provided by the hydantoin-transition metal complex. Concentration of N-methyl hydantoin is obtained based on the measured current signal using a calibration equation. The concentration of N-methyl hydantoin is correlated with concentration of creatinine to quantify the creatinine in the test sample.

An electrode composed of a substrate including a graphene layer coated on a first metal; and a complex including a second metal deposited on the substrate and a hydroxide of the first metal, where the complex is in the form of core-shell in which the second metal is a core and the hydroxide of the first metal is a shell, and the second metal has a higher standard reduction potential than the first metal. The graphene-coated metal foam of the present invention is the first case that proves not only theoretically but also by experiment that the remarkable catalytic ability reducing other metals (Au, Pt, Ag, and Cu, etc.) with a higher reduction potential than the metal by graphene coated on the metal surface it electroless deposition without additional reductant or electrical reduction conditions is due to the electrical double layer or interfacial dipole induced between the graphene and the metal.

Nanozymes capped with a radical-scavenging capping agent are disclosed for use in biosensing assays with improved sensitivity. The radical-scavenging capping agent facilitates the capture and retention of one or more radicals for enhancing a catalytic reaction. In some example embodiments, the nanozyme capped by the radical-scavenging capping agent is capable of catalyzing the decomposition of hydrogen peroxide or molecular oxygen. The capped nanozymes may be incorporated with an electrode, such as the working electrode of an electrochemical sensor, for achieving enhanced catalytic activity and a lower limit of detection. In some example embodiments, the radical-scavenging capping agent is or includes thiocyanate. A rapid ethanol detection device and associated method are described in which the working electrode of an electrochemical sensor is modified by a peroxidase-mimetic nanozyme capped with a radical-scavenging capping agent for the enhanced generation of a reduction current associated with the decomposition of hydrogen peroxide.

NADP-dependent oxidoreductase compositions, and electrodes, sensors and systems that include the same. Analyte sensors include an electrode having a sensing layer disposed thereon, the sensing layer comprising a polymer and an enzyme composition distributed therein. The enzyme composition includes nicotinamide adenine dinucleotide phosphate (NAD(P).sup.+) or derivative thereof; an NAD(P).sup.+-dependent dehydrogenase; an NAD(P)H oxidoreductase; and an electron transfer agent comprising a transition metal complex.

Provided are devices and methods for detecting a target molecule, based on using a graphene electrode. The devices exhibit high sensitivity to target molecules such as DNA that may be present at comparatively low concentrations.

Provided are devices and methods for detecting a target molecule, based on using a graphene electrode. The devices exhibit high sensitivity to target molecules such as DNA that may be present at comparatively low concentrations.

A Prussian blue/zinc oxide-carbon nanotube composite is provided, the nanotube composite being selective and sensitive for detection of hydrogen peroxide, which is important for screening for early cancer detection, monitoring cardiovascular disease, detecting onset of food spoilage, and enzymatic reactions that produce hydrogen peroxide as a byproduct. Also provided are methods using said zinc oxide-carbon nanotube composite in which standard addition is used in combination with chronoamperometry detection to quantify the level of hydrogen peroxide in a biological sample.