Abstract: A light-emitting composition containing first and second light-emitting markers. The first light-emitting marker comprises a first light-emitting material and a first binding group configured to bind to a first target analyte. The second light-emitting marker comprises a second light-emitting material which is different from the first light-emitting material and a second binding group which is different from the first binding group and which is configured to bind to a second target analyte. A luminescent lifetime of the first light-emitting material is shorter than a luminescent lifetime of the second light-emitting material. The difference in lifetimes of the first and second light-emitting materials may be used to distinguish between the first and second target analytes in a sample, e.g. by time-gated flow cytometry.

Abstract: A method of treating a reaction mixture comprising light-emitting nanoparticles formed upon reaction of a silica-forming compound in the presence of a light-emitting material in a protic, water-miscible solvent. The method comprises forming a phase-separated system comprising: an aqueous phase comprising the protic, water miscible solvent, an organic phase comprising an organic solvent and a separating solvent; and separating the organic phase. The separating solvent is immiscible with water, miscible with the water-miscible protic solvent and miscible with the organic solvent.

Abstract: A method of determining whether a test nucleotide comprises a base complementary to the next base of a template strand immediately downstream of a primer in a primed template nucleic acid molecule is described. The method comprises the use of a marked nucleotide comprising a test nucleotide conjugated to a light emitting marker by a linker.

Abstract: A conjugated light-emitting polymer comprising a host repeat unit and an intermediate repeat unit in a backbone of the conjugated light emitting polymer, and an emissive unit. The host repeat unit has a wider band gap than the intermediate unit. The intermediate repeat unit has a wider band gap than the emissive unit. The emissive unit is either: an emissive repeat unit of a block copolymer wherein the block copolymer comprises a first block comprising the intermediate repeat unit and the emissive repeat unit and a second block comprising the host repeat unit; a substituent of a proportion of the host repeat units and at least some of the host repeat units substituted with an emissive unit are arranged directly adjacent to an intermediate repeat unit; a substituent of a proportion of the intermediate repeat units; or a repeat unit in the backbone of the conjugated polymer and is arranged directly adjacent to the intermediate repeat unit.

Abstract: A method of identifying a target analyte in a sample containing a light-emitting marker configured to bind to the target analyte and detecting emission from the light-emitting marker. The light-emitting marker comprises a light-emitting polymer comprising a repeat unit of formula (I).

Abstract: A target analyte in a sample may be identified using a light-emitting ting marker is irradiated and emission from the sample at an emission wavelength of the light-emitting marker is detected. The method may be flow cytometry. The light-emitting marker comprises a light-emitting polymer comprising an electron-accepting repeat unit of formula (I) and an electron-donating repeat unit: (I) R1 and R2 independently in each occurrence is H or a substituent and X in each occurrence is dependently a substituent. The light-emitting marker may be a particulate light-emitting marker comprising particles containing the light-emitting polymer and a matrix material, e.g. silica.

Abstract: A light-emitting particle comprising a core comprising a matrix material and a light-emitting system comprising a polymer and a shell layer comprising an inorganic oxide in contact with and surrounding the core.

Abstract: A light-emitting particle comprising a core and a composite shell layer in contact with and surrounding the core wherein the composite shell layer comprises silica and a light-emitting polymer distributed across the thickness of the composite shell layer.

Abstract: A light-emitting marker having a light-emitting core comprising a light-emitting material bound to a first biotin group and a biomolecule bound to a second biotin group. A protein, e.g. streptavidin or neutravidin, is bound to the first and second biotin groups. The light-emitting marker may be a light-emitting marker particle having a particulate core.

Abstract: A method for determining the sequence of a polynucleotide is described. The method comprises detecting in a sequencing reaction the incorporation of a first, second, third, or fourth nucleotide using first and second excitation wavelengths and a photodetector having a detection window comprising a range of wavelengths.

Abstract: A particle comprising an inorganic matrix material; a first light-emitting material; and a second light-emitting material, wherein the first light-emitting material is a light-emitting polymer. The first and second light-emitting materials may have opposing ionic charges. The first light-emitting material may transfer excitation energy to the second light-emitting material. A biomolecule binding group may be bound to the particle.

Abstract: A light-emitting marker particle having a light-emitting particle core containing a light-emitting material and first and second surface groups bound to the light-emitting particle core. The first surface group contains a polar group and is an inert group which does not bind to a biomolecule. The second surface group contains a biomolecule binding group.

Abstract: A particle having an inorganic matrix material and a light-emitting polymer wherein the light-emitting polymer has a light-emitting group and a host repeat unit, wherein a bandgap of the host repeat unit is greater than that of the light-emitting group, wherein the light-emitting group makes up no more than 10 mol % of the groups of the light-emitting polymer and wherein the polymer has a solubility in water or a Ci-s alcohol at 20° C. of at least 0.1 mg/mL.

Abstract: The invention concerns a lateral flow assay device for determining the presence of an analyte in a liquid sample; the use of said device to test for the presence of an analyte in a liquid sample; and a method for determining the presence of an analyte in a liquid sample 5 involving the use of said device.

Abstract: A composite comprising silica and a light- emitting polymer comprising a backbone and polar groups pendant from the backbone.

Abstract: A method of testing a sample for the presence of nitrate or nitrite, the method comprising the steps of: forming a mixture by contacting the sample with a composition comprising hydrogen peroxide or a hydrogen peroxide precursor and a fluorescent indicator precursor capable of forming a fluorescent indicator in the presence of peroxynitrite; irradiating the mixture; and measuring fluorescence from the fluorescent indicator. The method may be carried out using a device in which the mixture in a channel or chamber 101 of a microfluidic device is irradiated by light from light source 103 and emission from the fluorescent indicator is detected by photodetector 105.

Abstract: A sensor comprising a light source (103); a photodetector (105); a sample receptacle such as a microfluidic device (101) between the light source and the photodetector; and one or both of a first light filter (107) and a second light filter (109) wherein the first light filter is provided between the sample receptacle and the photodetector and the second light filter is provided between the sample receptacle and the light source. The first light filter may comprise tartrazine. The second light filter may comprise Coomassie violet R200, Victoria Blue B or acid fuchsin. In use, light h?1 emitted from the light source is absorbed by a luminescent indicator in the sample receptacle which then emits light h?2 detected by the photodetector.

Abstract: A method of testing a liquid sample for the presence of an analyte, the method comprising the steps of: forming a mixture by contacting the sample with a composition comprising an oxidase for formation of hydrogen peroxide from the analyte, a fluorescent indicator precursor capable of forming a fluorescent indicator in the presence of an oxygen radical and an iron compound wherein the iron compound is dissolved in the mixture; irradiating the mixture; and measuring fluorescence from the fluorescent indicator. The method may be carried out using a device in which the mixture in a channel or chamber (101) of a microfluidic device is irradiated by light from light source (103) and emission from the fluorescent indicator is detected by photodetector (105).

Abstract: A sensor for detection of a biological analyte comprises: a bottom gate thin film transistor comprising a gate electrode (103); source and drain electrodes (107, 109); a dielectric layer (105) between the gate electrode and the source and drain electrodes; and a semiconductor layer (111) comprising an organic semiconducting material extending between the source and drain electrodes; a binding layer comprising an amphiphilic polymer comprising a binding group (115) adjacent to and in direct contact with the semiconductor layer; and a receptor (220) bound to the binding group.

Abstract: A sensor for detection of a target species is provided. The sensor includes a capture layer on an organic semi-conductor to which biomolecules may be bound. The capture layer polymer is deposited from a non-aqueous solution and the polymer is insoluble in water and has reactive groups for interaction with the analyte directly or via a conjugated species. Organic electronic devices, for example organic thin-film transistors having the capture layer are also provided. Use of a capture layer provides a low cost high quality biosensor which may be reliably produced in large quantities.