The DOSY experiment (Diffusion Ordered SpectroscopY) is the measure of diffusion coefficients by NMR. It has been developped in order to facilitate the complexe mixture analysis without physical separation.
Data acquisition and processing required dedicated NMR devices and softwares (NMRnotebook, DOSY Module) and can be speeded up with RDC.
This experiment will monitor any modification of the solvent or of the solutes, and molecular events such as molecular interactions or associations. It can also be used for the separation of molecules present in a mixture, separation based on their different diffusion properties.
There are many different applications:
- Trace detection and quantification
Application note available: Using DOSY for complexe mixture analysis
- Protein / ligand interaction screening (ligands fixed, even partially, to the target protein will see their diffusion coefficient modified). This technique can be applied successfully on ligand libraries.
- Molecular-mass and branching analysis of polymers
- Polluant or additive detection (polymers in liquids)
- Monomer / dimer equilibirum determination
In-tube NMR “chromatography”
- Determination of Critical Micellar Concentration