METHOD AND APPARATUS FOR THE DETECTION OF NONCOVALENT INTERACTIONS BY MASS SPECTROMETRY-BASED DIFFUSION MEASUREMENTS

摘要

The present invention provides a method and apparatus for detecting the noncovalent binding of a potential ligand (such as a drug candidate) to a target, e.g. a biochemical macromolecule such as a protein. The method is based on the Taylor dispersion of an initially sharp boundary between a carrier solution, and an analyte solution that contains the potential ligand(s) and the target. Dispersion profiles of one or more potential ligands are monitored by mass spectrometry at the exit of the laminar flow tube. Potential ligands will usually be relatively small molecules that have large diffusion coefficients. In the absence of any noncovalent interactions in solution, very steep dispersion profiles are expected for these potential ligands. However, a ligand that binds to a large target in solution, will show an apparent diffusion coefficient that is significantly reduced, thus resulting in a more extended dispersion profile. Noncovalent binding can therefore be detected by monitoring dispersion profiles of potential ligands in the presence and in the absence of the target. In contrast to other mass spectrometry-based methods for detecting noncovalent interactions, this method does not rely on the preservation of specific noncovalent interactions in the gas phase. This method has an excellent sensitivity and selectivity, therefore it can be used for testing multiple potential ligands simultaneously. The method is therefore useful for the high throughput screening of compound libraries.