Magnetic Separation of Proteins by a Self-Assembled Supramolecular Ternary Complex

The easy and effective separation of proteins from a mixture is crucial in proteomics. A supramolecular method is described to selectively capture and precipitate one protein from a protein mixture upon application of a magnetic field. A multivalent complex self‐assembles in a dilute aqueous solution of three components: magnetic nanoparticles capped with cyclodextrin, non‐covalent cross‐linkers with an adamantane and a carbohydrate moiety, and lectins. The self‐assembled ternary complex is precipitated in a magnetic field and readily redispersed with the aid of a non‐ionic surfactant and competitive binding agents. This strategy to purify proteins by supramolecular magnetic precipitation is highly selective and efficient. Separation by attraction: Proteins can be precipitated with a magnetic field by formation of a multivalent self‐assembled complex from cyclodextrin‐coated magnetic nanoparticles (MNPs), adamantane‐ and carbohydrate‐functionalized non‐covalent cross‐linkers, and lectin. This supramolecular approach to purify proteins is highly selective and efficient.