wearable devices, [4] soft electronics, [5,6] battery binders, [7][8][9] etc. Among these versatile materials, self-healing hydrogels, which can recover their original properties through autonomous healing after suffering from damages, exhibit an enormous potential in the fields of wound closure, [10,11] scaffolds for tissue engineering, [12,13] drug/cell delivery devices, [14][15][16] and so on.In nature, marine mussels can tightly attach to almost all surfaces by secreting mussel adhesive proteins (MAPs). [17] In addition, the adhesion property of MAPs is attributed to the presence of a special catechol-containing amino acid compound, 3,4-dihydroxyphenylalanine (DOPA). [18] The catechol groups of DOPA are easy oxidized to quinones in alkaline condition [1] and subsequently react with nucleophiles such as amines and thiols to form the 3D net structure of hydrogel via Schiff's base and Michael addition reactions. [19] Additionally, the catechol moieties endow DOPA with the capability to complex with various metal ions in order to produce coordination-crosslinked hydrogels. Owing to the versatility of DOPA, it has been coupled through various reactions to numerous macromolecules, including chitosan, [20] gelatin, [19] and polyethylene glycol (PEG). [21] This has allowed to fabricate mussel-inspired materials with self-healing and adhesive properties. The high price and potential neurotransmission effect of DOPA limit its commercial applications, however, and consequently the search of alternatives to DOPA is necessary. [22] Tannic acid (TA), a plant-derived polyphenolic compound, consists of a glucose core and ester-linked peripheral gallol groups (three adjacent hydroxyls attached to benzene). [23] With these functional groups, TA is capable to precipitate proteins (collagen and gelatin) by multi-point hydrogen bond and hydrophobic interactions. [24] The two adjacent phenolic hydroxyls of gallols in TA can also chelate metal ions (e.g., Fe 3+ , Al 3+ , Cr 3+ ) in the form of oxygen anion to form stable pentacyclic complexes. Although the third phenol hydroxyl is not involved in the formation of these pentacyclic structures, it can encourage the dissociation of the other two adjacent OH groups and accelerate the coordination reaction promoting its stability. [25] In addition, TA presents a good antioxidant capacity. The gallols of TA are oxidized to form quinones that further undergo nucleophilic Hydrogels Hydrogels, especially the ones with self-recovery and adhesive performances, have attracted more and more attention owing to their wide practical potential in the biomedical field involving cell delivery, wound filling, and tissue engineering. Tannic acid (TA), a nature-derived gallol-rich polyphenol, exhibits not only unique chelating properties with transition metal cations but also desirable anti-oxidation properties and strong bonding capability to proteins and gelatin. Thus, taking advantage of the versatility of TA, a one-pot method is proposed herein to produce TA-modified gelatin hydrogels with the aid ...

No abstract

No abstract

No abstract

Novel well‐defined redox‐responsive Ferrocene (Fc)‐containing amphiphilic dendronized diblock copolymers are synthesized by the ring‐opening metathesis polymerization technique using Grubbs’ third‐generation olefin metathesis catalyst as the initiator. These dendronized block copolymers can self‐assemble into spherical micelles in aqueous solution. The size of self‐assembled micelles can be modulated by the composition (namely, the ratio of hydrophobic and hydrophilic segments) and concentration of the dendronized copolymers. The obtained micelles show reversible redox‐controlled self‐assembly behaviors using FeCl3 as oxidant and glutathione as reductant. Furthermore, the model molecule Rhodamine B is successfully loaded in these micelles, and the oxidation‐triggered controllable release is achieved by changing the type of oxidants (FeCl3 and H2O2) and their concentrations. This is the first example of redox‐responsive micelles self‐assembled by novel amphiphilic dendronized Fc‐containing block copolymers, and the present micelles are visualized to be potential candidates in many fields, especially in stimuli‐responsive drug delivery systems.