Polydopamine coating in organic solvent for material-independent immobilization of water-insoluble molecules and avoidance of substrate hydrolysis

Polydopamine (pDA) coating is the first material-independent surface chemistry utilized in energy storage systems, environmental technology, and biomaterial science. However, the conventional coating method requires use of aqueous solutions, which restrict immobilization of water-insoluble molecules onto surfaces, and the coating cannot be applied to degradable polyester substrates. Herein, methods to form pDA in organic protic solvents (o-pDA) with fast coating kinetics resulting in ∼50 nm in thickness just for 4 h. One-step immersion of surfaces in a one-pot mixture of a water-insoluble molecule, dopamine, and piperidine results in o-pDA coating with robust surface immobilization of molecules of interest.