Immobilization of antibodies on a new solid phase for use in ELISA

Selective Recognition of Myoglobin in Biological Samples Using Molecularly Imprinted Polymer-Based Affinity Traps

The current work demonstrates the design, characterization, and preparation of molecularly imprinted microspheres for the selective detection of myoglobin in serum samples. The suspension polymerization approach was applied for the preparation of myoglobin imprinted microspheres. For this purpose, N-methacryloylamino folic acid-Nd3+ (MAFol- Nd3+) was chosen as the complex functional monomer. The optimization studies were performed changing the medium pH, temperature, and myoglobin concentration. pH 7.0 was determined as the optimum value where the prepared imprinted microspheres displayed maximum binding for myoglobin. The maximum binding capacity was achieved as 623 mgg-1. In addition, the selectivity studies were conducted. The results confirmed that the imprinted microspheres showed great selectivity towards myoglobin in the existence of hemoglobin, cytochrome c, and lysozyme which were chosen as potentially competing proteins.

A novel two-site immunoradiometric assay for beta-endorphin using nitrocellulose as solid phase

A two-site immunoradiometric assay for the highly specific direct quantitation of nonacetylated beta h-EP in crude brain tissue samples has been developed with a detection limit of 10 fmol per well. The assay used two different antibodies with distinct specificities: a polyclonal rabbit anti-beta h-EP antibody binding between the middle portion and the C-terminal end of beta h-EP was bound to nitrocellulose membrane discs, a solid phase with a high protein binding capacity. In the following two incubation steps, the beta h-EP containing crude tissue extract--or the beta h-EP-standard--and, subsequently, the 125I-labeled monoclonal 3-E7 mouse antibody directed against the N-terminus of beta h-EP were added. Binding of beta h-EP to the solid phase antibody in the first incubation step was not affected by the addition of cross reacting opioid peptides derived from beta h-LPH up to 10 pmol per disc. Nonspecific binding of the labeled antibody to the solid phase could be lowered to 3% of total counts by the use of PBS containing nonfat dry milk as blocking solution and incubation buffer, a procedure that did not reduce maximum specific binding. Dilution studies performed with extracts sampled from the anterior hypothalamus excluded the interference of tissue factors in the assay.