Question

Briefly describe the technique of In-vitro Binding Assays

Answer 1

These are also called the ligand binding assays.

These type of assays involve binding of ligand molecules to antibodies, receptors or macromolecules. A detection method determines the extent of binding of the ligand to the receptors.

There are 4 types of binding assays:

1. Radioactive ligand binding assays- Use radio-ligands which bind to the receptors and produce toxic radioactive wastes. e.g. saturation binding, scatchard plot, non linear curve fitting programs, competitive binding.

2. Non-radioactive ligand binding assays- Same as the radioactive ligand binding assays but do not produce the toxic radioactive waste. e.g. fluorescence polarization (FP), fluorescence rasonance energy transfer (FRET), surface plasmon rasonance (SPR)

3. Liquid phase ligand binding assays- Immunoprecipitation assays e.g. ELISA (Enzyme-linked immunosorbent assay) and western blotting.

4. Solid phase ligand binding assays- e.g. multiwell plate assays, on-column ligand binding assays, on-bead ligand binding assays, filter assays, real-time cell binding assays.

1) Radioactive ligand binding assays