Microtiter plates , 384-well Subject

In 1991, we first introduced the one-bead one-compound (OBOC ) combinatorial library method.1 Since then, it has been successfully applied to the identification of ligands for a large number of biological targets.2,3 Using well-established on-bead binding or functional assays, the OBOC method is highly efficient and practical. A random library of millions of beads can be rapidly screened in parallel for a specific acceptor molecule (receptor, antibody, enzyme, virus, etc.). The amount of acceptor needed is minute compared to solution phase assay in microtiter plates. The positive beads with active compounds are easily isolated and subjected to structural determination. For peptides that contain natural amino acids and have a free N-terminus, we routinely use an automatic protein sequencer with Edman chemistry, which converts each a-amino acid sequentially to its phenylthiohydantoin (PTH) derivatives, to determine the structure of peptide on the positive beads. 

A systematic approach to profiling active metabolites using a 96-well plate format was recently described (Shu et al., 2002). The approach is based on a rapid bioassay-guided metabolite detection and characterization. Drug metabolite mixtures (generated by various methods described below) are separated and fractions collected into microtiter plates such as 96-well plates. The fractions are then subjected to one or more relevant activity (e.g., receptor ligand binding) assays. 

By far the most exploited ELISAs use plastic microtiter plates in an 8 j A 12 well format as the solid phase (7). Such systems benefit from a large selection of specialized commercially available equipment including multichannel pipets for the easy simultaneous dispensing of reagents and multichannel spectrophotometers for rapid data capture. There are many books, manuals, and reviews of ELISA and associated subjects that may be examined for more practical details (8"C21). The following table summarizes some of the features that make ELISA so sustainable a technique. 

The MIC value which is defined as the minimum concentration of an antimicrobial that is able to restrict the growth of microbial after whole night incubation have been determined by broth dilution method. Initial concentration of the nanocomposites for the test is taken as 10 mg/ml and diluted twice in each time up to a concentration of 0.0195 mg/ml. Nanocomposites with different concentrations have been subjected to E. coli and S. aureus to investigate the value of MIC. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoIiiun bromide) is added to the solution after 16 h incubation in Luria Berteni media in 96 well microtiter plate and incubated for 45 min in dark. Live bacterial cells which are capable to produce succinate dehydrogenase (enzyme) which reacts with MTT and forms formazan complexes with purple appearance. So the well having minimum concentration of sample where the complex does not form i.e. which does not appear purple is considered as the MIC value of the compound and is presented in the Table 7. It is observed that the MIC value of the nanocomposites decreases with the increase in Ag-NPs concentration in the nanocomposites and is minimum in the case of nanocomposites with 15 wt% of Ag-NPs. 

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