The present invention provides methods of detecting analytes using particles having different physico-chemical properties, such as buoyancy, size, density, spectral characteristics, and/or binding properties, in solution-based sandwich assays and solution-based competition assays. The methods can be performed using rotors and bench-top centrifuges and provide for rapid, qualitative and quantitative detection of analytes. The present invention also provides kits that can be used to perform the methods, and mixtures containing particles suitable for the methods.

Some embodiments disclosed herein provide a plurality of compositions each comprising a protein binding reagent conjugated with an oligonucleotide. The oligonucleotide comprises a unique identifier for the protein binding reagent it is conjugated with, and the protein binding reagent is capable of specifically binding to a protein target. Further disclosed are methods and kits for quantitative analysis of a plurality of protein targets in a sample and for simultaneous quantitative analysis of protein and nucleic acid targets in a sample. Also disclosed herein are systems and methods for preparing a labeled biomolecule reagent, including a labeled biomolecule agent comprising a protein binding reagent conjugated with an oligonucleotide.

The methods and systems described herein provide capture template particles and an improved emulsion droplet-based target capture and barcoding method thereof. The capture template particles and methods disclosed herein allow capturing targets of interest from biological samples, and barcoding of specific nucleic acids contained in the captured targets. The nucleic acids can be contained within living or nonliving structures, including particles, viruses, and cells. The nucleic acids can include, e.g., DNA or RNA.

Compositions comprising multiple hydrogel particles having substantially the same diameter, but with each subgrouping of particles from the multiple hydrogel particles having different associated values for one or more passive optical properties that can be deconvoluted using cytometric instrumentation. Each hydrogel particle from the multiple hydrogel particles can be functionalized with a different biochemical or chemical target from a set of targets. A method of preparing hydrogel particles includes forming droplets and polymerizing the droplets, with optional functionalization.

The present invention provides a membrane carrier 3 comprising a flow path 2, wherein a microstructure is formed at a bottom of the flow path 2, and a particle to which an antibody or an antigen binds is arranged in at least a part on the flow path, the particle having a diameter of 500 nm or more and 100 μm or less.

Some embodiments of the disclosure provide a time-resolved fluorescent immunochromato-graphic test strip for detecting vancomycin as well as a preparation method and application thereof. In some embodiments, the test strip includes a bottom plate and a sample absorption pad. A fluorescent microsphere pad, a nitrocellulose membrane coated with a vancomycin-carrier protein conjugate, and an absorbent pad are sequentially overlapped and pasted on the bottom plate. The fluorescent microsphere pad is sprayed with a fluorescent microsphere-labeled vancomycin monoclonal antibody, and the vancomycin monoclonal antibody is prepared by using a vancomycin-bovine serum albumin conjugate as an immunogen.

A method includes attaching two or more beads to each unit of one or more units of a chemical component in a sample, to form, for each unit of the chemical component, a multi-bead complex including two or more beads and the unit of the chemical component; placing the sample on a surface of an image sensor; at the image sensor, receiving light originating at a light source, the received light including light reflected by, refracted by, or transmitted through the beads of the multi-bead complexes; at the image sensor, capturing one or more images of the sample from the received light; and identifying, in at least one of the images of the sample, separate multi-bead complexes, the identifying of the separate multi-bead complexes including associating the two or more beads of each of the multi-bead complexes based on proximity to one another.

A particle-based assay system is disclosed that uses hydrogel microparticles that capture analytes of interest from a sample which are subsequently bound with catalytic reporter complexes. Catalytic reporter complexes bound to the hydrogel microparticles generate signals that are accumulated in the vicinity of the hydrogel microparticle at high concentration (or on or within the hydrogel microparticles). In some circumstances, the reporter complex-bound hydrogel microparticles are encapsulated in an emulsion. Preferably, the emulsion is substantially uniform and contains one hydrogel microparticle per droplet. The accumulated signal generated by the catalytic reporter complexes is contained inside the emulsion, and/or optionally immobilized onto or inside the hydrogel microparticle. Signals are read and analyzed using optical instruments such as flow cytometers. Breaking the emulsion prior to signal analysis is optional. In some embodiments, a sample is introduced to hydrogel microparticles in a dried state to concentrate analytes of interest.

A system and method for handling a sample comprising particles (CE) bound to ferromagnetic particles (FP); a magnetic field is created in a container (3) inside which the sample (TS) is arranged so that the particles (CE) are attracted against a side wall (4) of the container (3); part of the sample (TS) is sucked through a cannula (8), kept in position by an alignment device (10) so as not to be in contact with the side wall (4) of the container (3), without withdrawing the particles (CE) that remain in contact with the side wall (4).

Methods for enhancing the binding rate between at least two particulate binding partners are disclosed. Methods include flowing a first binding partner and a second binding partner, e.g., in a viscoelastic fluid, under conditions to chemically bind the first binding partner and the second binding partner to create a third binding partner. The flow conditions induce a particle size dependent, migration, e.g., radial, velocity differential between the first binding partner and the second binding partner and between the first binding partner and third binding partner, e.g., to increasing a collision frequency of the nanoparticles and the larger particles. Devices for enhancing the binding rate between at least two particulate binding partners are also disclosed.