Plate technique for folate assay.

Plate-dilution frequency technique for assay of microbial ecology.

The plate-dilution frequency technique described facilitates simultaneous enumeration of a wide range of physiologically different microorganisms in complex systems with a precision comparable to dilution tube (most probable number) methods. Replicate microsamples are inoculated from each member of a dilution series onto areas delineated on plates of prepoured solid media; the plates are incuba...

Dried-serum spot assay for folate.

Dual-substrate plate diffusion assay for proteases.

A plate diffusion assay for endopeptidases was developed. Proteases applied to plates containing 1% casein, 1% gelatin, and 1.5% agar caused distinct zones reminiscent of immunoprecipitation bands. The diameter of the zones was linearly proportional to the log of the enzyme activity applied over a range from 0.01 to greater than 100 IU/ml.

Microtiter plate immunoenzymometric assay for estrogen receptor.

The estrogen receptor (ER) status of breast cancer is used both as a prognostic factor and as a predictor of response to endocrine therapy. An immunoenzymometric assay for ER was developed on 96-well microtiter plates (EIA96). This technique involves two monoclonal antibodies directed against different epitopes in the B domain of ER. The two-step protocol (16-18 h and 3 h at 4 degrees C) requir...

Assay of serum and whole blood folate by a modified aseptic addition technique.

There are wide discrepancies in studies published by different laboratories between results of assays of serum and red cell folate activity (SFA and RCF) in normal subjects, but many of these differences are likely to be the result of variations of technique, rather than of the population being studied. There are basically three techniques in the assay of SFA using Lactobacillus casei as the te...