A random terpolymer of N-(2-hydroxypropyl) methacrylamide, carboxybetaine methacrylamide and sulfobetaine methacrylamide, and a polymer brush and to a functionalized polymer brush containing this terpolymer are disclosed. The random terpolymer increases the resistance of the substrate surface to non-specific adsorption of substances from biological media and/or to non-specific interaction with biological media components, and is suitable for use in the form of a polymer brush, for example in sensors or membranes.

The present disclosure relates to a kit for quantitative detection using a fluorescent microarray, and belongs to the technical field of protein detection. The kit of the present disclosure includes a detection plate and a detection antibody coupled with fluorescent microspheres, where the detection plate is provided with a plurality of reaction chambers; the reaction chamber is provided with an opening, and an inner bottom surface of the reaction chamber is provided with a plurality of detection sites that are arranged side by side along a length direction of the reaction chamber at an interval. The kit of the present disclosure may detect allergen-specific IgE, IgG and IgA with high sensitivity, as well as rapidly and quantitatively detect an allergen-specific antibody IgE, IgG and IgA concentration in human serum or plasma, and may screen dozens of allergens at a time.

The present invention provides a method for preparing colloidal palladium nanoparticles and using them for increased sensitivity in lateral flow immunoassays. Glutaraldehyde is used in preparing the colloidal palladium that allows rapid attachment of biomolecules. Colloidal palladium nanoparticles are labeled with a protein, such as a biomolecule or an antibody. These labeled colloidal palladium particles catalytically develop a dye to detect the presence of an analyte.

There is provided a surface functionalized with cross linking groups adapted to receive antibodies and/or fragments thereof. The surface has an antibody binding biomolecule having a linker region which is covalently crosslinked to functional groups and an antibody binding region. The surface also has a cell interacting biomolecule having a linker region which is covalently crosslinked to functional groups of the surface and a cell interacting region that imparts functional attributes including cell adhesion, spreading, proliferation, differentiation and/or a functional response. The two biomolecules are present in independently controlled concentrations and have similar small molecular weights.

Biotin derivatives, methods of using the biotin derivatives and kits comprising the biotin derivatives.

The methods described herein provide a means of producing an array of spatially separated proteins. The method relies on covalently attaching each protein of the plurality of proteins to a structured nucleic acid particle (SNAP), and attaching the SNAPs to a solid support.

It was discovered that hydrogel scaffolds can be used to induce phase separation as aqueous two-phase systems (ATPSs) pass through and/or rehydrate the scaffolds, allowing for concentration of target analyte(s) (e.g., biomolecule(s)) into a particular phase of the ATPS or into a leading front. Accordingly, in various embodiments methods and devices are provided that utilize aqueous two-phase systems and hydrogel scaffolds to improve the sensitivity of assays (e.g., of point-of-care assays) without sacrificing cost or ease of use.

A method for amplification in a microfluidic assay, includes binding an analyte to a transport element, wherein the transport element includes a particle and a first antibody element and the analyte is bound to the first antibody element; moving the transport element with the analyte towards a tracer storage site including tracer elements which includes a first binder element, a label element and a second antibody element; binding the analyte to the second antibody element; moving the transport element with the analyte and the tracer element towards a tracer transport site including second binder elements; binding the first binder element with a second binder element; moving the transport element with the analyte towards the tracer storage site so that the analyte is detached from the second antibody element of the tracer element while the first binder element remains bound to the second binder element.

In a flow cytometry measurement method, an analysis medium is provided, which includes a fluid and biological cells contained therein. A labeling molecule is provided and is brought in contact with the analysis medium in such a way that the labeling molecule can bind specifically to a target structure located on the surface of the cell if the cell has said cell structure. For the individual cells, flow cytometry measured values are captured for a first and a second physical parameter. The first parameter is fluorescence radiation emitted by the labeling molecule when the labeling molecule is excited. The cells are classified on the basis of the flow cytometry measured values. A first calibrator and a second calibrator are provided, which have solid particles matching in shape, size and material. A target structure matching the target structure of the cells is immobilized on the surface of the first calibrator. The second calibrator does not have said target structure. The calibrators are mixed with the analysis medium before the flow cytometry measured values are captured. Corresponding first and second flow cytometry measured values are captured for the calibrators as well as for the cells. A normalized first flow cytometry measured value for the cell is formed from the first flow cytometry measured value of the first calibrator, the first flow cytometry measured value of the second calibrator and the first flow cytometry measured value of the cell.

A graphene-based sandwich immunoassay for detecting whether a target biological substance is present in a sample, generally comprising contacting said sample with a plurality of particles coated with graphene nanosheets, each particle having at least one targeting receptor, such that the target biological substance, if present, associates with the targeting receptor, and detecting the presence of the target biological substance in the sample by subsequently contacting the sample with a detection antibody, wherein the detection antibody is capable of targeting and binding with the target biological substance if bound to the targeting receptor to yield a detectable complex. The targeting receptor can be an antibody or fragment thereof. The target biological substance can be an exosome.