Mussel-inspired conductive hydrogels are attractive for the development of next-generation self-adhesive, flexible skinlike sensors. However, despite extensive progress, there are still some daunting challenges that hinder their applications, such as inferior optical transparency, low catechol content (e.g., poor adhesion), as well as limited sensation performances. Here, we report a dopamine-triggered gelation (DTG) strategy for fabricating mussel-inspired, transparent, and conductive hydrogels. The DTG design leverages on the dual functions of dopamine, which serves as both polymerization initiator and dynamic mediator to elaborate and orchestrate the cross-linking networks of hydrogels, allowing for pronounced adhesion, robust elasticity, self-healing ability, excellent injectability and three-dimensional printability, reversible and tunable transparent-opaque transition, and thermoresponsive feature. These preferable performances enable DTG hydrogels as self-adhesive, flexible skinlike sensors for achieving multiple sensations toward pressure, strain, and temperature, even an extraordinary visual perception effect, making it a step closer in the exploration of future biomimetic skin.

Functional vascularization is critical for the clinical regeneration of complex tissues such as kidney, liver or bone. The immobilization or delivery of growth factors has been explored to improve vascularization capacity of tissue engineered constructs, however, the use of growth factors has inherent problems such as the loss of signaling capability and the risk of complications such as immunological responses and cancer. Here, a new method of preparing water-insoluble silk protein scaffolds with vascularization capacity using an all aqueous process is reported. Acid was added temporally to tune the self-assembly of silk in lyophilization process, resulting in water insoluble scaffold formation directly. These biomaterials are mainly noncrystalline, offering improved cell proliferation than previously reported silk materials. These systems also have appropriate softer mechanical property that could provide physical cues to promote cell differentiation into endothelial cells, and enhance neovascularization and tissue ingrowth in vivo without the addition of growth factors. Therefore, silk-based degradable scaffolds represent an exciting biomaterial option, with vascularization capacity for soft tissue engineering and regenerative medicine.

The research of carbon-based antivirals is still in its infancy, and their development into safe and effective carbon dots (CDs) with antiviral activity at multiple points in the life cycle of the virus remains to be explored. Here, we report a one-step method to apply curcumin in order to prepare of uniform and stable cationic carbon dots (CCM-CDs) with antiviral properties. The inhibitory effect of CCM-CDs on viral replication was studied by using porcine epidemic diarrhea virus (PEDV) as a coronavirus model. PEDV is applied as a coronavirus model to study the antiviral effect of as-prepared CCM-CDs on its replication. The cationic CCM-CDs treatment is found obviously to inhibit the proliferation of PEDV compared with the common CDs (EDA-CDs). The CCM-CDs treatment can change the structure of surface protein in viruses, thereby inhibiting viral entry. It can also suppresses the synthesis of negative-strand RNA of the virus, the budding of the virus, and the accumulation of reactive oxygen species by PEDV. Furthermore, CCM-CDs treatment is also found to suppress viral replication by stimulating the production of interferon-stimulating genes (ISGs) and proinflammatory cytokines. These results offer theoretical support for the development of CCM-CDs as a hopeful antiviral drug for the treatment of coronavirus infections, including PEDV.

No abstract

Developing nanomaterials-based antimicrobial agents has shown a widespread promise. In this study, silver nanoparticle-modified graphene oxide (GO-AgNPs) nanocomposites were self-assembled via interfacial electrostatic force. By using the porcine reproductive and respiratory syndrome virus (PRRSV) as a pattern, the antiviral effect of the as-prepared GO-AgNPs nanocomposites on the replication of virus was investigated. The results indicated that exposure with GO-AgNPs nanocomposites could obviously suppress PRRSV infection. It was found that GO-AgNPs nanocomposites exhibited a better inhibitory effect compared with AgNPs and GO. By selecting the porcine epidemic diarrhea virus (PEDV) as a contrast virus, GO-AgNPs nanocomposites were proven to have a broad antiviral activity. Mechanism studies showed that GO-AgNPs nanocomposites might prevent PRRSV from entering the host cells, with 59.2% inhibition efficiency. Meanwhile, GO-AgNPs nanocomposite treatment enhances the production of interferon-α (IFN-α) and IFN-stimulating genes (ISGs), which can directly inhibit the proliferation of virus. Taken together, this study reports a new type of antiviral agent and provides a promising pharmaceutical agent for treating infection by the highly pathogenic PRRSV. Moreover, it may provide novel ideas for the research and development of antiviral formulations based on nanocomposites and extend their applications in biological systems.