Detecting single molecules includes binding the single molecules to a surface of an optically transparent substrate, irradiating the surface of the substrate with light having an incident angle selected to achieve total reflection of the light, thereby scattering light from the surface and from the single molecules bound to the surface, and collecting light scatted by the surface and by the single molecules bound to the surface to form a series of images. Systems for detecting single molecules include an optically transparent substrate, a means for flowing a sample solution over a surface of the substrate, a light source configured to irradiate the surface, a camera, and a collection optical system configured to collect light scatted by the surface and by the target molecules on the surface to form a series of images on the camera.

An apparatus for testing a fluid sample including a sample receiving member having an opening for receiving a fluid sample, wherein the sample receiving member comprises at least a first and second sample collection chambers, a sample retention member, in fluid communication with the first sample collection chamber, to retain a portion of the fluid sample, and at least one test strip, in fluid communication with the second collection chamber, to indicate the presence or absence of at least one analyte in the fluid sample, wherein the first collection chamber is not in fluid communication with the second collection chamber.

The present invention relates to a switching binder binding to an antigen-binding portion of an antibody, a preparation method thereof, and a pharmaceutical composition, an assay kit, and an antigen and antibody assay method, each utilizing the same. A switching binder according to an embodiment of the present invention includes an amino acid sequence selected from framework regions of a heavy chain or a light chain, which constitutes an antigen-binding portion of an antibody, wherein the amino acid sequence includes, in addition to the heavy chain or the light chain, a first antibody-binding portion or a second antibody-binding portion that binds to a framework region of a heavy chain or a light chain, which constitutes the antigen-binding portion, the amino acid sequence being able to bind specifically to the antigen-binding portion of the antibody and then be separated from the framework region when a target antigen is provided.

A method for predicting patient survival comprises determining a level of STK1 (serum thymidine kinase 1) material in a body sample from a patient diagnosed with prostate cancer using an antibody or a fragment thereof specifically binding to a serum form of human TK1. The method also comprises predicting survival of the patient based on the determined level of STK1 material in the body sample.

Provided is a non-invasive and prompt testing method, in which a mucus adhering onto the surface of a mucous membrane is used as a specimen.

A method for collecting a specimen by wiping out a mucus adhering onto the surface of a mucous membrane, when the specimen is collected during an endoscopic examination.

The present disclosure provides a test strip for milk immunofluorescence assay (IFA) and use thereof, and relates to the technical field of test strip. The test strip of the present disclosure includes a sample pad, a conjugate pad, a nitrocellulose membrane, and a wicking pad assembled and pasted successively on a PVC backing card; fluorescent latex microsphere-labeled mixed antibodies are coated on the conjugate pad; anti-casein antibody (T1 line), anti-beta-lactoglobulin (BLG) antibody (T2 line), anti-alpha-lactalbumin (ALA) antibody (T3 line), anti-lactoferrin/anti-bovine serum albumin (BSA) antibody (T4 line), and rabbit anti-mouse IgG antibody (C line) are coated on the nitrocellulose membrane, where the T1, T2, T3, and T4 lines are test lines, and the C line is a control line. The test strip of the present disclosure accurately and quantitatively detects the content of casein, BLG, ALA, and lactoferrin/BSA in food, and features easy operation and high accuracy and sensitivity.

Methods and systems for capture object-based assays, including for determining a measure of the concentration of an analyte molecule or particle in a fluid sample, are described. The methods and systems may relate to high sensitivity detection of analytes, sometimes using assay conditions and sample handling that result in the capture and detection of a high percentage of the analyte molecules or particles in a fluid sample using relatively few capture objects. Apparatuses and methods for immobilizing capture objects with respect to assay sites, in some instances with unexpectedly high efficiencies are also described. Some such apparatuses involve the use of force fields and fluid meniscus forces, alone or in combination, to facilitate or improve capture object immobilization. Also described are techniques for utilizing a relatively high percentage of capture objects in an assay sample, such as by using disclosed sample washing techniques, imaging systems, and analysis procedures that can reduce capture object loss.

Provided herein is a rapid lateral flow device for detection of a target analyte in a liquid biological sample comprising a membrane strip, the membrane strip including: a matrix; a conjugate pad having at least one reporter vitrified into the matrix; one or more test sites including a covalently or electrostatically bound capture agent vitrified into or onto the matrix; and, optionally, a control line including one or more capture agents vitrified into or onto the matrix. Also provided are methods of rapid detection of a target analyte in a liquid biological sample.

Provided herein, in some embodiments, are rapid diagnostic tests to detect one or more target nucleic acid sequences (e.g., a nucleic acid sequence of one or more pathogens). In some embodiments, the pathogens are viral, bacterial, fungal, parasitic, or protozoan pathogens, such as SARS-CoV-2 or an influenza virus. In one embodiment, a rapid test method is provided comprising performing an isothermal nucleic acid amplification-based rapid test, accessing fluorescence data of a reaction tube of the test, and visually detecting, via the fluorescence data, presence or absence of a target pathogen, such as COVID-19 and/or an influenza virus and/or a target nucleic acid.

The present disclosure relates to a device including a reagent portion in which a chemiluminescent indicator and a chemiluminescent substrate for the indicator are disposed, and a base on which the reagent portion is formed. The chemiluminescent indicator and the chemiluminescent substrate are disposed independently from each other in the reagent portion in such a manner that the chemiluminescent indicator and the chemiluminescent substrate can react with each other when a sample is supplied to the reagent portion. The present disclosure also relates to a remote diagnosis system including an imaging terminal for detecting a luminescent signal generated when a reagent is supplied to the device and an information processing unit for processing luminescent signal data obtained by the imaging terminal. The imaging terminal and the information processing unit can bi-directionally communicate with each other via a network.