Provided herein is technology relating to sensors for detecting an analyte and particularly, but not exclusively, to liquid crystal sensors, methods of producing liquid crystal sensors, and methods of using liquid crystal sensors.

Systems and methods for the controlled release of a guest composition that is sequestered within a host composition made up of an anisotropic fluid are disclosed. The guest composition is immiscible in the host composition, thus forming an interface between the compositions upon which elastic repulsion forces act to prevent the release of the guest composition from the host composition. The disclosed systems and methods work by changing the elastic repulsion forces and/or introducing one or more counter forces such that the elastic repulsion forces are no longer sufficient to prevent release of the guest composition. Exemplary methods include mechanically changing the host material (e.g., changing its temperature) or inducing a chemical (e.g., electrostatic) attraction sufficient to overcome the elastic repulsion forces. The disclosed systems and methods can be used for a variety of applications requiring “on-demand” delivery of a chemical composition.

The response of biological cells to applied stress is central to the functioning of living systems. The present disclosure is directed to systems, compositions and methods for rapidly reporting biomechanical properties of cells or cellular organelles at a single cell or population level.

Liquid crystal-based devices for detecting a target contaminant in air, including hydrogen, nitrogen dioxide, ozone, ammonia or carbon monoxide, and methods of using such devices to detect the target contaminant are disclosed. Such devices have a substrate surface that includes one or more metals or metal alloys that is in contact with a liquid crystal composition. When the device is contacted with a sample that contains the target contaminant, an observed change in the orientational ordering of the liquid crystal signals the presence of the target contaminant. In the absence of the target contaminant, no change in orientational ordering occurs.

A liquid crystal element including: two substrates having a transparent conductive layer formed thereon, the substrates being arranged so that the transparent conductive layers face each other, and a liquid crystal-polymer composite film sandwiched between the two substrates having a transparent conductive layer, wherein the liquid crystal-polymer composite film includes a polymer matrix and a liquid crystal composition surrounded by the polymer matrix, the liquid crystal composition contains a liquid crystal component and a dichroic dye, the liquid crystal component has positive dielectric constant anisotropy, and has an NI point of 110° C. or higher and 150° C. or lower, the liquid crystal component has a refractive index anisotropy of 0.01 or more and 0.1 or less, and the liquid crystal-polymer composite film can be switched between a transparent state and a colored state by applying a voltage.

Liquid crystal-based devices for detecting chlorine in a sample and methods of using such devices to detect chlorine are disclosed. Such devices have a substrate surface that includes either metal cations or a metal that is in contact with a composition that includes a liquid crystal. When the device is contacted with a sample that contains chlorine, an observed change in the orientational ordering of the liquid crystal signals the presence of the chlorine. In the absence of chlorine, no change in orientational ordering occurs.

Provided herein is technology relating to sensors for detecting an analyte and particularly, but not exclusively, to liquid crystal sensors, methods of producing liquid crystal sensors, and methods of using liquid crystal sensors.

A liquid crystal composition includes a nematic liquid crystal, and a compound of Formula (I) where R is an alkyl, aryl, aralkyl or heteroaryl having 6 to 30 carbon atoms, wherein the compound accounts for 0.3 to 0.6% of the liquid crystal composition. ##STR00001## Further, a sensing device includes a substrate, a frame, an alignment film, the liquid crystal composition as described above, and two polarizers. The frame is connected to the substrate and forms an accommodation space having an opening, and the alignment film and the liquid crystal composition are both located inside the accommodation space. One of the polarizers is arranged in correspondence with the opening such that a channel exists between the polarizer and the frame, the other polarizer is located at a lateral side of the substrate, and the polarization directions of the two polarizers intersect with each other.

The present invention relates to devices for the regulation of light transmission and in particular to switchable windows. The present invention in particular relates to window elements which comprise electrically switchable optical cells with a switchable layer containing a liquid-crystalline medium having a clearing point which is within the working temperature of the window element. The present invention also relates to liquid-crystalline media for use in the window elements.

The present invention relates to heteroaromatic isothiocyanates of formula N

##STR00001##

as defined in claim 1, to liquid-crystalline media comprising one or more compounds of formula N and to high-frequency components comprising these media, especially microwave components for high-frequency devices, such as devices for shifting the phase of microwaves, tunable filters, tunable metamaterial structures, and electronic beam steering antennas, e.g. phased array antennas.