41 articles
Acetylene reduction assay
The acetylene reduction assay (ARA) estimates nitrogenase activity by incubating a sample with acetylene and measuring the ethylene formed by gas chromatography, a mainstay of nitrogen fixation research since the late 1960s.
Assay
An assay is an analytical method in which a set of reagents generates a detectable signal used to quantify a biological process, drug development, and clinical diagnostics.
ATPase assay
An ATPase assay is a biochemical measurement of ATP hydrolysis by ATPase enzymes, most commonly quantifying released inorganic phosphate, used to functionally characterize new ATPases and measure their turnover rates.
Bio-layer interferometry
Bio-layer interferometry (BLI) is a label-free, dip-and-read optical technique that measures biomolecular binding kinetics, affinity, and concentration using disposable biosensor tips, widely used in antibody discovery and drug screening.
Biopanning
Biopanning is an iterative affinity-selection technique in which phage display libraries are repeatedly screened against a target molecule to enrich rare clones displaying high-affinity binders, a core method in antibody discovery.
Cellular thermal shift assay
The cellular thermal shift assay (CETSA) is a bench biology method that tests drug binding inside living cells by heating treated cells and measuring soluble target protein.
Co-immunoprecipitation
Co-immunoprecipitation (co-IP) is a bench biology method that uses an antibody to pull a target protein and its bound partners out of native cell lysate.
Deep mutational scanning
Deep mutational scanning is a bench biology method that measures how up to about 1 million protein mutations affect function, using pooled selection and high-throughput sequencing to score each variant.
Differential scanning fluorimetry
Differential scanning fluorimetry (DSF), also called the thermal shift assay or ThermoFluor, heats a protein while monitoring fluorescence to measure its melting temperature and ligand binding.
ELISA
ELISA, or enzyme-linked immunosorbent assay, is a laboratory method using enzyme-linked antibodies to detect and quantify substances like antibodies, antigens, and hormones in liquid samples.
Gelatin zymography
Gelatin zymography is a gel-based enzyme activity assay in which gelatin cast into an SDS-polyacrylamide gel is digested by separated gelatinases, detecting MMP-2 and MMP-9 as clear bands.
High-throughput screening
High-throughput screening (HTS), also known as high-throughput experimentation, is a drug discovery method that uses automated, miniaturized assays to test hundreds of thousands to millions of compounds against disease targets.
Homogeneous assay
A homogeneous assay is a biochemical assay format that measures molecular binding or enzymatic activity with no separation or wash step, so mix-and-read protocols suit automation and high-throughput screening.
Immunoassay
Immunoassay: antibody-based biochemical test quantifying analytes like hormones, drugs, and viruses in blood. Developed as radioimmunoassay by Yalow and Berson (Nobel 1977); formats include RIA, ELISA, and sandwich chemiluminescent assays; limitations include hook effect and antibody interference.
Immunohistochemistry
Immunohistochemistry (IHC), or immunohistochemical staining, is a laboratory method that uses antibody-bound enzymes or fluorescent dyes to detect antigens in tissue, widely used to diagnose cancer.
In vitro digestion model
An in vitro digestion model is a laboratory method that simulates human gastrointestinal digestion outside the body, using sequential enzymatic treatments to measure digestibility and nutrient release.
Inhibition assay
An inhibition assay is a bench biology method measuring how a competitor reduces a target's binding or activity, yielding percent inhibition, IC50, and an inhibition constant (Ki).
Lateral flow test
Lateral flow test, also called lateral flow immunoassay or rapid diagnostic test: a single-use capillary-flow strip assay giving results in 10–20 minutes; first commercialized as the 1984 Unipath pregnancy test, used for malaria, HIV, COVID-19 and more.
Ligand binding assay
A ligand binding assay is a laboratory method that measures the binding of a ligand, such as a drug or hormone, to its target receptor or protein.
Luciferase assay
A luciferase assay measures light from a luciferase reporter enzyme in cell lysates, living cells, or whole animals as a quantitative proxy for promoter activity, gene expression, or ATP.
Mammalian two-hybrid assay
The mammalian two-hybrid assay is a cell-based method that tests protein interactions in mammalian cells by reconstituting a transcription factor that drives a reporter gene.
Microscale thermophoresis
Microscale thermophoresis (MST) is an optical biophysical method that measures biomolecular binding in free solution by moving fluorescently labeled molecules in a laser-induced temperature gradient, yielding affinities in about 10 minutes without surface immobilization.
MTT assay
MTT assay: colorimetric cell viability test from Mosmann's 1983 method; tetrazolium salt reduced by living cells to formazan, read near 570 nm; measures metabolic activity, not direct cell counts.
Primer exchange reaction
The primer exchange reaction (PER) is an isothermal DNA reaction in which a catalytic hairpin template repeatedly copies sequences onto a primer, growing concatemers used in SABER FISH and biosensing.
Protein interaction mapping
Protein interaction mapping is the set of experimental methods, including yeast two-hybrid and affinity purification mass spectrometry, that identify physical interactions between proteins and assemble them into interaction networks.
Protein microarray
A protein microarray is a glass slide or chip on which many proteins are immobilized at high density, measuring binding events and interactions in parallel.
Protein-fragment complementation assay
A protein-fragment complementation assay detects protein-protein interactions in living cells by splitting a reporter into inactive fragments that regain activity when the fused proteins interact, read out by fluorescence, luminescence, or survival.
Protein–protein interaction screening
Protein–protein interaction screening is a set of bench methods for testing which proteins interact: yeast two-hybrid reports binary contacts, while affinity purification with mass spectrometry reports stable complexes.
Proximity ligation assay
The proximity ligation assay (PLA) is a bench biology method, introduced in 2002, that detects proteins and their interactions by converting nearby antibody binding into amplifiable DNA.
Radioimmunoassay
Radioimmunoassay (RIA), developed by Rosalyn Yalow and Solomon Berson at the Bronx VA hospital, is a competitive antibody-based technique using radioactive labels such as iodine-125 to measure hormones like insulin at nanogram or picogram levels; it won Yalow the 1977 Nobel Prize.