We describe a new multianalyte immunoassay principle and apply it to the simultaneous immunoassay of lutropin, follitropin, choriogonadotropin, and prolactin in serum. The method is based on the coating of distinct areas of polystyrene with analyte-specific antibodies. These antibodies react with the analyte and immobilize it in a specific area while another biotinylated antibody also reacts wi...

We developed a method for quantitatively determining theophylline in serum, using a heterogeneous immunoassay called flow-injection immunoanalysis. The reaction involves competition between serum theophylline and theophylline-labeled liposomes. Separation occurs on a solid-phase reactor column containing immobilized antibody to theophylline incorporated in a flow-injection system. Subsequent ly...

Selected recent advances in immunoassay are reviewed. Development has continued on new labels (beta-lactamase, pyrophosphatase, luciferases, photoproteins, pyridopyridazines, europium cryptates, metal carbonyl complexes, porphines, phosphors) and label-detection methods (e.g., chemiluminescence assays, thermometric assays, NADP(+)- and FADP-based coupled assays). Various methods have been explo...

In this clinically useful enzyme immunoassay of digoxin in serum, we mix sample, beta-galactosidase-labeled digoxin, and anti-digoxin Fab fragments for 30 min at room temperature, then use Sepharose-bound second antibody for phase separation, and measure the unbound enzyme activity directly in the supernate of the equilibrium reaction mixture. The immunoassay buffer--phosphate-buffered isotonic...

In a solid-phase immunoassay, binding between an antigen and its specific antibody takes place at the boundary of a liquid and a solid phase. One of the reactants (receptor) is immobilized on a surface. The other reactant (ligand) is initially free in solution. We present a theory describing the kinetics of immunochemical reaction in such a system. A single essential restriction of the theory i...

We used enzyme immunoassay to measure apolipoprotein B concentration in human plasma. Pure lipoprotein B was isolated from serum samples of fasting normolipidemic subjects by sequential preparative ultracentrifugation and coated to a polystyrene tube surface by adsorption. Human serum samples and rabbit antiserum to human apolipoprotein B were incubated with the solid-phase lipoprotein B. Solub...

A novel, simple, economical, and environmentally friendly tunable immunosorbent-based immunoassay for sensitive and selective determination of atrazine is reported. Tunable immunosorbents consisting of a fusion between an elastin-like polypeptide made up of 77 repeating units of the pentapeptide VPGVG and a single-chain Fv of an anti-atrazine antibody were synthesized biologically and purified ...

background: enzyme linked immunosorbent assay (elisa) has been described as an alternative to radioimmunoassay for the mammalian and nonmammalian steroids detection. in this study, a simple and rapid elisa is described and validated for 4-pregnen-3,20, dione (progesterone). materials and methods: a general procedure for preparation of the acetylcholinesterase labelled steroid is described which...

An immunoassay system based on enzyme immunoassay technology has been developed for quantitative panel testing. The system includes test card disposables, reagents, and an instrument. Patients' samples are processed semiautomatically in the instrument with minimum user intervention. The test card has multiple test areas at individual locations on a membrane solid phase so that simultaneous dete...