Table 2 Typical applications of smart and versatile biomaterials

Hemostasis

Visible light

Eosin Y (as a PS), GelMA, hemocoagulase.

The adhesive incorporated snake venom hemagglutinase and Eosin Y into GelMA, which rapidly cross-linked to form a hydrogel under visible light irradiation.

Based on mouse rat tail dissection and rat liver incision models, the bioadhesive was demonstrated to reduce the clotting time from 5–6 min to about 45s, with an approximately 80% reduction in bleeding volume.

[64]

Antibacterial

Light (PDT, PTT)

Gold nanoclusters (Au NCs)

Using an in situ method of growth, gold nanoclusters modified zirconium-based porphyrin metal–organic frameworks (Au NCs@PCN) were constructed.

Under near-infrared (NIR) laser irradiation, Au NCs@PCN can be heated to 56.2 °C and generate ROS, showing an effective killing effect on bacteria.

[65]

Anti-inflammation

ROS.

Nanozymes.

Using a one-step method that is simple and effective to fabricate ultrasmall Cu5.4O NPs (Cu5.4O USNPs)

Cu5.4O USNPs as nanozymes possessed multiple enzyme-mimicking and broad-spectrum ROS scavenging ability, as well as cytoprotective effects against ROS-mediated damage.

[66]

Pro-vascularization

Light.

Collagen.

Laser irradiation of the hydrogel generates cavitation gas bubbles, which rearrange the collagen fibers, resulting in stable microchannels (diameters: 20–60 μm).

Such 3D channels can enable the formation of artificial microvasculature by culturing endothelial cells, as well as cell media perfusion.

[67]

Regulation of wound microenvironment

-

Chitosan, HA, collagen, etc.

A hydrogel-based burn dressing prepared by one-pot fabrication process.

In rabbits, this hydrogel substance greatly expedited the healing of deep II degree burn lesions, indicating that it has great potential for trauma repair.

[68]

Self-healing wound dressing for motional wound

Mechano-stimuli.

GelMA and tannic acid (TA).

A self-heal double-network hydrogel fabricated with GelMA and tannic acid.

GelMA-TA gel has potential use in skin wound closure, sutureless gastric surgery, and strain sensing.

[69]

Self-removal wound dressing

Redox

Dopamine, PEG.

An injectable dopamine-based adhesive hydrogel containing PVI.

The adhesive strength is rapidly reduced by spraying Zn2 + solution, which was attributed to the established metal ion complexing between Zn2 + and PVI.

[70]

Monitoring

Thermo and light (UV).

UV light-emitting diodes, temperature sensor, and UV-responsive hydrogel.

A smart flexible electronics-integrated wound dressing real-time monitoring and on-demand therapy of infected wounds.

The combined UV-responsive antibacterial hydrogel and UV-light were activated at the commencement of infection, allowing the loaded antibiotic to be released in-situ into the wound site.

[71]

Scar management

Light.

ALA, HAase and Met.

An anti-scar strategy based on ALA-mediated PDT, combined with HAase based dissolving microneedles and Met.

HAase significantly enhanced the transdermal delivery efficiency of ALA. And HAase (as a “spear”) combined with Met (as a “shield”) greatly strengthed the anti-scar outcomes of PDT.

[72]

Versatile biomaterials

pH and glucose.

Phenylboronic acid, benzaldehyde, chitosan.

A pH/glucose dual-responsive Met release hydrogel dressings with adhesive and self-healing capabilities contributed by dual-dynamic bonding.

Based on a rat type II diabetic foot model, the hydrogel was demonstrated to promote wound healing by reducing inflammation and enhancing angiogenesis.

[73]