Non‐Covalent Self‐Assembly and Covalent Polymerization Co‐Contribute to Polydopamine Formation

Abstract

Polydopamine is the first adhesive polymer that can functionalize surfaces made of virtually all material chemistries. The material‐independent surface modification properties of polydopamine allow the functionalization of various types of medical and energy devices. However, the mechanism of dopamine polymerization has not yet been clearly demonstrated. Covalent oxidative polymerization via 5,6‐dihydroxyindole (DHI), which is similar to the mechanism for synthetic melanin synthesis, has been the clue. Here, it is reported that a physical, self‐assembled trimer of (dopamine)2/DHI exists in polydopamine, which has been known to be formed only by covalent polymerization. It is also found that the trimeric complex is tightly entrapped within polydopamine and barely escapes from the polydopamine complex. The result explains the previously reported in vitro and in vivo biocompatibility. The study reveals a different perspective of polydopamine formation, where it forms in part by the self‐assembly of dopamine and DHI, providing a new clue toward understanding the structures of catecholamines such as melanin.

Highly effective photothermal chemotherapy with pH-responsive polymer-coated drug-loaded melanin-like nanoparticles

“…PDA was synthesized according to the method of dopamine oxidation and self-polymerization in an alkaline environment. 4 The solution became dark as the oxidation reaction progressed because the PDA surface contained catechol, which was susceptible to oxidization during polymerization. 24 Through the "Michael addition and Schiff" base reaction, bifunctional PEG amine was attached to functionalize the PDA NPs in Tris buffer.…”

Induction and control of supramolecular chirality by light in self-assembled helical nanostructures

“…The long-range corrected hybrid density functional with damped atom-atom dispersion correction, oB97X-D, was used 52 . This functional can handle p-p interaction empirically and have been successfully used to model polymer structures with large number of atoms [53][54][55] . The 6-31G* basis set was used to describe atomic orbitals.…”

Probing polydopamine adhesion to protein and polymer films: microscopic and spectroscopic evaluation

“…The mussel adhesive-inspired polydopamine (PD) appears to be an ideal biomaterial coating since it fulfils all these criteria. It exhibits low cytotoxicity [2], antibacterial properties [3,4], promotes cell growth [5][6][7][8], resists corrosion [9], can aid antibiotic release [10,11], is simple to produce with control over film thickness [12] and can be attached to a variety of surfaces including silanes [13], metals [9,14], polymers [7,[15][16][17] dentine [18] and even hair [19].…”