Mesoporous silica nanoparticles (MSNs) are recognized as a prime example of nanotechnology applied in the biomedical field, due to their easily tunable structure and composition, diverse surface functionalization properties, and excellent biocompatibility. Over the past two decades, researchers have developed a wide variety of MSNs-based nanoplatforms through careful design and controlled preparation techniques, demonstrating their adaptability to various biomedical application scenarios. With the continuous breakthroughs of MSNs in the fields of biosensing, disease diagnosis and treatment, tissue engineering, etc., MSNs are gradually moving from basic research to clinical trials. In this review, we provide a detailed summary of MSNs in the biomedical field, beginning with a comprehensive overview of their development history. We then discuss the types of MSNs-based nanostructured architectures, as well as the classification of MSNs-based nanocomposites according to the elements existed in various inorganic functional components. Subsequently, we summarize the primary purposes of surface-functionalized modifications of MSNs. In the following, we discuss the biomedical applications of MSNs, and highlight the MSNs-based targeted therapeutic modalities currently developed. Given the importance of clinical translation, we also summarize the progress of MSNs in clinical trials. Finally, we take a perspective on the future direction and remaining challenges of MSNs in the biomedical field.

This article reviews the degradability of chemically synthesized bioelastomers, mainly designed for soft tissue repair. These bioelastomers involve biodegradable polyurethanes, polyphosphazenes, linear and crosslinked poly(ether/ester)s, poly(ε-caprolactone) copolymers, poly(1,3-trimethylene carbonate) and their copolymers, poly(polyol sebacate)s, poly(diol-citrates) and poly(ester amide)s. The in vitro and in vivo degradation mechanisms and impact factors influencing degradation behaviors are discussed. In addition, the molecular designs, synthesis methods, structure properties, mechanical properties, biocompatibility and potential applications of these bioelastomers were also presented.

Infection is the major reason for GTR/GBR membrane failure in clinical applications. In this work, we developed GTR/GBR membranes with localized drug delivery function to prevent infection. Hierarchical membranes containing micro- and nano-fibers were fabricated. The effects of the incorporation of gelatin and loading content of metronidazole (MNA) (0, 5, 10, 20, 30, and 40 wt% polymer) on the properties of the electrospun membranes were investigated. The interaction between PCL and MNA was identified by molecular dynamics simulation. MNA was released in a controlled manner, and the antibacterial activity of the released MNA remained. The incorporation of gelatin and MNA improved the hydrophilicity, biocompatibility, and in vitro biodegradation rate of PCL nanofibers. The electrospun membranes allowed cells to adhere to and proliferate on them and showed excellent barrier function. The membrane loaded with 30% MNA had the best comprehensive properties. Subcutaneous implantation results demonstrated that MNA-loaded membranes evoked a less severe inflammatory response than pure PCL nanofibers. These results demonstrated the potential of MNA-loaded membranes as GTR/GBR membranes with antibacterial and anti-inflammatory functions for biomedical applications.