[Object] To provide a formaldehyde detecting sensor capable of constantly monitoring formaldehyde selectively and with high accuracy. [Solving Means] A formaldehyde detecting sensor according to the present invention includes: a reaction portion that contains at least a hydroxylamine salt and reacts with formaldehyde to generate an acid; and a response unit that includes an electrode carrying a carbon material, an electrical resistance value of the carbon material varying depending on the acid generated in the reaction portion, in which the hydroxylamine salt and the carbon material are separated from each other.

A sensor for sensing diols and triols includes a substrate, a conductive coating, and two electrodes. The conductive coating is disposed on the substrate and has affinity for binding with a substance selected from the group consisting of diols, triols, and a combination thereof. The conductive coating includes PEDOT:PSS and a humectant, which together constitute at least 95 weight percent of the conductive coating. The two electrodes are in contact with the conductive coating to probe conductivity of the conductive coating so as to detect the substance from a reduction of the conductive coating's conductivity.

A sensor for carbon dioxide can include an amidine functional group.

Disclosed herein are embodiments of compositions for gas sensing and sensors utilizing the same. In one embodiment, a composition comprises carbon nanotubes and polymer-coated metal nanoparticles bound to the carbon nanotubes.

A method of manufacturing a composite material, comprising providing a conductive polymer having a hydrophilic end and adding a metal oxide, such that the metal oxide is connected to the hydrophilic end of the conductive polymer, wherein the metal oxide is obtained by subjecting a metal oxide precursor to a dehydration reaction, a polymerization reaction, a condensation reaction, or a combination thereof.

A gas sensing device includes a substrate, a conductive unit, and a sensing layer. The conductive unit is disposed on the substrate, and includes two electrodes. The sensing layer is disposed on the conductive unit, and is electrically connected with the electrodes. The sensing layer adapted to absorb carbon dioxide includes polyethyleneimine and polyethylene glycol. A detecting system including a testing device, an analyzing device and the aforementioned gas sensing device is also disclosed. The gas sensing device is detachably mounted to and is electrically connected to the testing device. Electrical property of the gas sensing device 100 changes when the gas sensing device 100 absorbs carbon dioxide.

A polymer material is contained in a sensing film of a sensor element having a quartz plate, an electrode made of a metal film provided on the quartz plate, and a sensing film provided on the electrode, and has a structural unit that contains one or more ethylene unsaturated bonds and is originated from a compound containing one or more functional groups reactive to a gas.

A power transfer-based flexible sensing platform that can be used in a fluid environment includes at least one metallic thin film structure, with a polymeric encapsulation that protects the metallic thin film structure from the fluid environment, a smart hydrogel sandwiched between layers of the metallic thin film structure, the smart hydrogel being configured to swell or shrink in response to stimulus, and an AC power source or signal generator electrically connected to the at least one metallic film structure. The metallic thin film can include first and second U-shaped metallic thin film structures, each encapsulated, where the smart hydrogel is sandwiched between them. An AC power or signal source is electrically connected to one of the U-shaped structures, causing power to be inductively transferred to the other. Measurement of the induced power or other signal can be used to determine a concentration of an analyte in the fluid environment.

An apparatus for selectively detecting an anion in a medium and/or selectively measuring the concentration of an anion in a medium. The apparatus comprises at least one sensor and a conductive polymer film and is configured such that dielectric and/or electric property changes of the conductive polymer film can be detected by the sensor when the conductive polymer film is in hydraulic contact with the medium or after it has been in hydraulic contact with the medium. Methods of selectively detecting an anion in a medium and/or selectively determining a concentration of an anion in a medium are also provided.

Provided herein are devices (e.g., electrochemical sensors useful for detecting volatile organic compounds associated with certain diseases or conditions and/or diagnosing certain diseases or conditions). The devices comprise one or more layers of metal on a layer of silicon, and a layer of molecularly imprinted polymer in electrical communication with the one or more layers of metal, wherein the one or more layers of metal are each independently selected from a layer of chromium, platinum, gold, nickel, cobalt, tungsten, rhodium, iridium, silver, tin, titanium or tantalum, or an alloy thereof. Methods of using the devices (e.g., to detect one or more analytes in a sample, to detect and/or diagnose a disease or condition in a subject), and methods of making the devices are also provided.