An automated microfluidic bioreactor device and methods to rapidly detect drugs of abuse from human sweat are provided. The bioreactor can perform either single-plexed measurements (detecting only one target analyte at a time) or multiplexed measurement (detecting multiple analytes simultaneously). The bioreactor device has a cartridge comprising a capillary array that employs competitive enzyme-linked immunosorbent assay (ELISA) to detect the presence of various drugs or metabolite compounds. For example, four common drugs, methadone, methamphetamine, amphetamine, and tetrahydrocannabinol, were detected rapidly and quantitatively in about 16 minutes with a low sweat sample volume (about 4 μL per analyte) and a large dynamic range (methadone: 0.0016 ng/mL-1 ng/mL; METH: 0.016 ng/mL-25 ng/mL; amphetamine: 0.005 ng/mL-10 ng/mL; THC: 0.02 ng/mL-1000 ng/mL).

The present invention addresses the problem of providing a method for measuring 25-hydroxy vitamin D and a measurement reagent, the method and the reagent being based on a competitive immunoassay. The present invention provides a reagent for measuring 25-hydroxy vitamin D based on a competitive immunoassay, which includes at least the following composition: (1) a Vitamin D derivative represented by the chemical formula (I) and/or (II), (2) an anti-25 hydroxy vitamin D antibody. In addition, the present invention provides a reagent for measuring vitamin D based on a competitive latex turbidimetric immunoassay (competitive LTIA) in which, in particular, a vitamin D derivative or an anti-25-hydroxy vitamin D antibody is immobilized on latex.

The present invention relates to the field of protein characterization, and in particular to methods for identifying critical quality attributes of therapeutic proteins by implementing a workflow including using a competitive binding assay with insufficient capture molecule followed by LC-MS.

The present disclosure provides assay methods for the detection and/or quantification of an analyte in a sample. In some examples, the methods detect and/or quantify an active analyte in a sample.

The present disclosure relates to the development of novel immunoassays for the detection of SARS-CoV-2 or secreted spike protein (or fragments thereof) in saliva, nasal mucosal sample, throat samples, or nasopharyngeal samples.

Disclosed herein are immunoassay methods for detecting and quantifying human neutrophil elastase (HNE) generated fragments of calprotectin in a biofluid sample; and monoclonal antibodies and assay kits for use in such methods. The methods may be used for detecting, monitoring and/or determining the status or severity of a disease characterized by or exhibiting inflammation in a patient.

Provided herein are protein biosensors, fusion proteins, compositions, and methods that are useful in detecting SARS-CoV-2 viruses in a sample from a subject. The viral detection assays described herein are solution-based, rapid, and quantitative. The protein biosensors and fusion proteins herein are able to bind to SARS-CoV-2 viral proteins. Use of the fusion proteins in proximity assays (e.g., split reporter assays) allows sensitive detection of SARS-CoV-2 virus in samples.

The invention discloses an anti-phenacetin monoclonal antibody hybridoma cell strain AD, a preparation method and application thereof, and relates to the technical field of food safety immunodetection. The monoclonal antibody hybridoma cell strain is named monoclonal cell strain AD and the number CGMCC19681. The Phe-BA obtained by the hydrolysis of the reaction product of the phenacetin metabolite acetaminophen and ethyl 4-bromobutyrate is used as the hapten, and the hapten is coupled with the carrier protein to prepare the immunogen Phe-BA-BSA. After the mice were immunized with the immunogen Phe-BA-BSA, they were fused with myeloma cells by PEG method, screened by indirect competitive enzyme-linked immunosorbent assay and subcloned five times to obtain hybridoma cell lines. The monoclonal antibody secreted by the cell line can be made into a phenacetin detection kit, which has good affinity and detection sensitivity for phenacetin, and can be used for immunodetection of phenacetin residues in food.

A diagnostic assay strip includes a first layer that includes an iron mobile labelled specific binding partner that will bind to and iron biomarker from a sample and produce an iron complex and a vitamin A mobile labelled specific binding partner that will bind to a vitamin A biomarker from the sample and produce a vitamin A complex. A second layer includes iron and vitamin A test regions, and a control region. The iron test region has immobilized specific binding partners that will bind to the iron complex. The vitamin A test region has immobilized vitamin A biomarker that will bind to vitamin A mobile labelled specific binding partner, which is not bound to the vitamin A biomarker, passing from the first layer to the second layer. The control region has a moiety which will non-specifically bind to and immobilize the iron and vitamin A labelled specific binding partners. Methods of using the diagnostic assay strip are also discussed.

A microdevice includes: a microchannel to which a measurement target solution containing a measurement target substance is introduced; an antibody being fixed to at least one sidewall surface of the microchannel and specifically binding to the measurement target substance; a fluorescence-labeled derivative being specifically bound to the antibody and being acquired by fluorescence-labeling the measurement target substance; and a light blocker blocking excitation light exciting fluorescent light radiated by the fluorescence-labeled derivative. The measurement target substance and the fluorescence-labeled derivative specifically bind to the antibody in a competitive manner, and the antibody is fixed to the sidewall surface of the microchannel in a state of specifically binding to the fluorescence-labeled derivative. The light blocker blocks the excitation light entering the fluorescence-labeled derivative specifically binding to the antibody.