Issue link: https://resources.nanotempertech.com/i/1050614
4 On the industry side of the research spectrum, binding affinity is a useful metric during the earliest parts of the drug development process when scientists are screening for any compounds that interact with their target of interest. Beginning with a large library of compounds or ligands, industry scientists begin the screening process by identifying which ones bind to the target protein, and then continue with an increasingly smaller pool of compound candidates. A er they complete much of their pre-clinical work, researchers may measure binding affinity to determine and rank various compounds' binding affinities for the target protein as an indicator of potency of a possible drug candidate. Scientists use many different tools to measure binding affinity, although most of them fall into one of two categories: qualitative methods and quantitative methods. Qualitative methods such as ELISAs, pull-down assays, and gel shi assays work by immobilizing one protein to a substrate and applying another protein (typically containing a label or reporter tag) to it. If the two proteins bind, they release a detectable signal. These methods merely provide a yes/no answer as to whether binding occurred. These techniques may be suitable for labs that occasionally analyze protein interactions or are examining protein interactions at a very gross level. In contrast, quantitative methods provide a scalar readout of binding affinity, releasing a signal that indicates the strength of the interaction. Biosensor-based methodologies work by immobilizing a binding partner to a surface and presenting the test partner to interact with it. The change in signal is observed and recorded by the instrument. Other quantitative methods use capillaries or tubes instead of immobilizing proteins to a surface. In this section, we'll walk through the most common biophysical technologies and their strengths and weaknesses in terms of throughput, speed, sensitivity, and ease of use. What tools are available to measure binding affinity? QUALITY COUNTS When it comes to measuring binding affinity, or performing any other experiment, for that matter, the quality of your results will depend on the quality of the source material. If you don't have any data on the quality of your source material, the experiment is less likely to succeed.