Microtiter plate format

A high-throughput method using a 96-well microtiter plate format and plate UV spectrophotometry has been described [26]. Solubilities at a single pH, or at <12 pH values can be determined, using one of two methods. 

We have developed chemiluminescent immunoenzymatic assays for (3-ago-nist drugs in the 96-well-microtiter-plate format. Such competitive assays have been used for determination of clenbuterol and of the overall content of p-agonist drugs in the sample. They matched the standard requirements of precision and accuracy, and were more sensitive compared to the conventional colorimetric methods. Moreover, CL detection was very rapid, making these assays suitable for screening analysis. 

HCA refers to the application of a recently developed technology that consolidates and automates microscopy, cytochemistry, imaging and bioinfomatics. These are applied to cells in various microtiter plate formats or on glass slides. Multiple morphologic features and fluorescence signals can be measured simultaneously. 

The modified Lowry assay can also be done in a 96-well microtiter plate format. The assay has a working range of 1 to 1500 pg/ml. 

Fig. 28 Schematic view of the Zeiss Plate Vision instrument which is state-of-the art for ultra-high throughput screening (uHTS) for drug discovery. The instrument resembles a 96-well parallel microscope the light of a excitation source (Xe-lamp or pulsed laser) is expanded to illuminate a microtiter plate. The excitation is structured into 96 channels by a mini-lens array (MLA) and focused into the well with a detection volume of < 100 nL. All 96 channels are read simultaneously by a gated, intensifed CCD. With this fast detector and the pulsed laser excitation, the instrument can be used to carry out miniaturized, 96 parallel lifetime measurements in microtiter plate format with nanosecond time resolution or time-gated detection [190]...

For expression of BCCP-p53 fusion proteins, we typically found the protein concentration in crude lysates to be 5 mg/mL, and we estimated that BCCP-p53 was present at approx 1% of total soluble protein. When expressing a number of clones in parallel for array fabrication, the Bradford assay can conveniently be done on all clones in parallel using a microtiter plate format. However, it would be laborious to carry out SDS-PAGE analysis on all clones, so typically we assess only a selection of clones in this way, since the absolute expression level is not critical for array fabrication. 

There are many ways to estimate microbial growth. The simplest is visual inspection of colonies growing on agar plates, though this method is difficult to adapt for HTS. There is a well-known correlation between cell density and optical density, which can be exploited in a 96-well microtiter plate format (e.g., [43]). Measurement of the incorporation of radioactive nutrients is an excellent quantitative method, but has fallen from favor due to concerns about spills and contamination. Finally, both spectrophotometric and fluorimetric assays are conveniently adapted to HTS formats, and Alamar blue is only one example of the tools available for this purpose. As mentioned, we have even found it convenient to use simple visual inspection of Alamar blue plates to identify wells of interest. However, quantification obtainable with a microplate reader is attractive in many settings. 

Geysen et al. [1] introduced this method for generating peptides in a reusable form. In this method, peptides are synthesized on polyaciylate-grafted polyethylene pins arranged in standard 96-well microtiter plate format, and screening is performed by an enzyme-... 

The commercially available Enzygnost HBe monoclonal kit (distributed by Dade Behring) can be considered as an example for an immunoassay which combines many favorable features, e.g. nonisotopic label, sandwich immunoassay principle, use of monoclonal antibodies, determination of antigen and anti-antigen antibodies in a single test, microtiter plate format, possibility for semi- and fully automation. 

Function of mitochondria is also commonly monitored as an indicator of cellular toxicity. Mitochondrial uptake and retention of the fluorescent dye, rhodamine 123, can be visualized microscopically. Biochemical measurements of mitochondrial function include the ATP-ADP ratio and dehydrogenase activity with MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide), which yields a colored formazan product upon reduction. The dye, neutral red (3-amino-7-dimethyl-amino-2-methylphenazine hydrochloride), targets lysosomes, and its retention is inversely related to cytotoxicity. Commercially available versions of the MTT and neutral red assays have been adapted to microtiter plate formats to provide highly efficient screening assays. Examples of how cell-type-specific functions can be followed as indicators of cell toxicity are included in Table 8.1. 

The microtiter plate array format involves immobilizing carbohydrates in wells of 96-, 384-, or 1536-well microtiter plates (see Fig. la). Each carbohydrate component is spatially separated from other components within the plate. Two of the primary advantages of a microtiter plate format are cost and simplicity. Carbohydrates can be distributed into wells using multichannel pipettors, and assay results can be measured using standard plate readers. Thus, the equipment and supplies needed for the array are relatively inexpensive and common. However, microtiter plates generally require larger amounts of each carbohydrate and can accommodate a smaller total number of components per support unit. 

An alternative to the microtiter plate format is a glass microscope slide. Slides can come in various layouts. The array developed by Glycominds, Ltd. contains 200 microwells with... 

Just as in microtiter plate format based screening, compartmentalization is also used in selection methods each DNA-protein pair is spatially isolated in an individual compartment, which is either a cell (in vivo selection) or a manmade compartment (in vitro selection) instead of individual wells. 

Microtiter Plate Formatting for the Titration of a Virus Stock in PBMCs... 

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