Full‐thickness skin injuries have always been an intricate problem in clinical treatment. The application of biomaterials provides an artificial matrix for the recruitment of cells and deposition of extracellular matrix to accelerate wound healing. For the recovery of full‐thickness skin defects, the double cross‐linking of MgO‐catechol and Schiff's base bonds are used as part of the gel‐forming mechanism, and a bio‐multifunctional hydrogel (CCOD‐MgO) is prepared by adding MgO to catechol‐modified chitosan (CHI‐C) and oxidized dextran (ODex). The CCOD‐MgO demonstrates high tissue adhesion, excellent self‐repairing, hemostasis function, and low swelling rate. With the addition of MgO and catechol chelation, the adhesion strength of CCOD‐MgO is about 35 kpa, which is much greater than fibrin glue. Moreover, the CCOD‐MgO has better antibacterial properties than CHI‐C/ODex hydrogel (CCOD) due to the synergy of chitosan and MgO in vitro. Accordingly, the CCOD‐MgO can protect the wounds from infection and accelerate the healing speed of the epidermis in full‐thickness cutaneous defect and burn model in vivo. These results demonstrate that the CCOD‐MgO would be a promising therapeutic strategy in full‐thickness skin injuries for clinical therapies.

Physiological microenvironment engineering has shown great promise in combating a variety of diseases. Herein, we present the rational design of reinforced and injectable blood-derived protein hydrogels (PDA@SiO2-PRF) composed of platelet-rich fibrin (PRF), polydopamine (PDA), and SiO2 nanofibers that can act as dual-level regulators to engineer the microenvironment for personalized bone regeneration with high efficacy. From the biophysical level, PDA@SiO2-PRF with high stiffness can withstand the external loading and maintaining the space for bone regeneration in bone defects. Particularly, the reinforced structure of PDA@SiO2-PRF provides bone extracellular matrix (ECM)-like functions to stimulate osteoblast differentiation via Yes-associated protein (YAP) signaling pathway. From the biochemical level, the PDA component in PDA@SiO2-PRF hinders the fast degradation of PRF to release autologous growth factors in a sustained manner, providing sustained osteogenesis capacity. Overall, the present study offers a dual-level strategy for personalized bone regeneration by engineering the biophysiochemical microenvironment to realize enhanced osteogenesis efficacy.

Optical biosensors, especially those based on plasmonic structures, have emerged recently as a potential tool for disease diagnostics. Plasmonic biosensors have demonstrated impressive benefits for the label‐free detection of trace biomarkers in human serum. However, widespread applications of these technologies are hindered because of their insufficient sensitivity, their relatively complex chemical immobilization processes, and the use of prism couplers. Accordingly, a sandwiched plasmon ruler (SW‐PR) based on a Au nanohole array with ultrahigh sensitivity arising from the plasmonic coupling effect is developed. Highly confined surface charges caused by Bloch wave surface plasmon polarizations substantially increase the coupling efficiency. This platform exhibits thickness sensitivity as high as 61 nm nm−1 and can detect at least 200 000‐fold lower analyte concentrations than a nanowell sensing platform with the same wavelength shift. Additionally, the sandwiched plasmonic biosensor allows precise and label‐free testing of clinical biomarkers, namely C‐reactive protein and procalcitonin, in patient serum samples without requiring a sophisticated prism coupler, extra antibodies, or a chemical immobilization technique. This study yields new insight into the structural design of plasmon rulers and will open exciting avenues for disease diagnosis and therapy follow‐up at the point‐of‐care.

Despite malignant tumors being one of the most serious diseases threatening human health and living quality, exploring theranostic agents for highly effective tumor diagnosis and treatment is still full of challenges. Herein, we demonstrate the design and preparation of Tween-20-modified BiVO4@Bi2S3 heterojunction nanorods (HNRs) for multimodal computed tomography (CT)/photoacoustic (PA) imaging and radiotherapy (RT)/radiodynamic therapy (RDT)/photothermal therapy (PTT) synergistic therapy. Benefiting from the high X-ray attenuation coefficient of Bi, BiVO4@Bi2S3 HNRs exhibit a sensitive CT imaging capacity and radiation enhancement effect during RT. Meanwhile, the strong NIR absorption of Bi2S3 endows BiVO4@Bi2S3 HNRs with an excellent PA imaging and photothermal transformation capacity. More importantly, by taking advantage of the type II band alignment between BiVO4 and Bi2S3, an extra internal electric field is established to accelerate the separation of X-ray-induced electrons and holes in BiVO4@Bi2S3 HNRs, resulting in the realization of highly effective X-ray-induced RDT. Because the in vitro and in vivo experiments have verified that the RT/RDT/PTT synergistic therapeutic efficacy is greatly superior to any single treatment, it is believed that our BiVO4@Bi2S3 HNRs can be used as the multifunctional nanotheranostic platform for malignant tumor theranostics.

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The ultimate goal of cutaneous wound healing is to reform a stratified epithelium to restore the normal epidermal barrier, which involves the epithelial-to-mesenchymal transition (EMT) process. However, the healing strategies...

Neuroanatomical tracing is considered a crucial technique to assess the axonal regeneration level after injury, but traditional tracers do not meet the needs of in vivo neural tracing in deep tissues. Magnetic resonance (MR) and photoacoustic (PA) imaging have high spatial resolution, great penetration depth, and rich contrast. Fe 3 O 4 nanoparticles may work well as a dual-modal diagnosis probe for neural tracers, with the potential to improve nerve regeneration. The present study combines antegrade neural tracing imaging therapy for the peripheral nervous system. Fe 3 O 4 @COOH nanoparticles are successfully conjugated with biotinylated dextran amine (BDA) to produce antegrade nano-neural tracers, which are encapsulated by microfluidic droplets to control leakage and allow sustained, slow release. They have many notable advantages over traditional tracers, including dual-modal real-time MR/PA imaging in vivo, long-duration release effect, and limitation of uncontrolled leakage. These multifunctional anterograde neural tracers have potential neurotherapeutic function, are reliable and may be used as a new platform for peripheral nerve injury imaging and treatment integration.

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