Enhanced diabetic wound repair remained a global challenge. Herein, we reported a novel hydrogel with glucose-responsive hyperglycemia regulation and antioxidant activity for enhanced diabetic wound repair. In this study, gallic acid (GA) with strong antioxidant activity was grafted onto chitosan (CS) chains by one-step synthesis, and then incorporated into poly (ethylene glycol) diacrylate (PEG-DA) hydrogel matrix to obtain a novel antioxidant hybrid hydrogel (PEG-DA/CS-GA). Meanwhile, polyethyleneimine (PEI) was modified with a unique glucose-sensitive phenylboronic acid (PBA) molecule to load insulin (PEI-PBA/insulin nano-particles, PEI-PBA/insulin NPs), which could be immobilized in the PEG-DA/CS-GA hybrid hydrogel by the formation of dynamic borate bond between the phenylboronic acid groups on the PEI-PBA and the polyphenol groups on the CS-GA. The results indicated that the PEG-DA/PEI-PBA/insulin/CS-GA (PPIC) hydrogel platform not only had remarkable biocompatibility, but also displayed extraordinary antioxidant properties (DPPH scavenging rate > 95.0%), and effectively protected cells from oxidative damage (decreased MDA levels, increased Superoxide dismutase (SOD) levels and stable GSH/GSSG levels). Meanwhile, the PPIC hydrogel also exhibited unique glucose-responsive insulin release characteristics, and effectively regulated the blood glucose level. The in vitro and in vivo results demonstrated that our PPIC hydrogel could promoted angiogenesis (increased VEGF and CD 31 expression), reshaped the inflammatory microenvironment (decreased IL-6 and increased IL-10 level), and achieved wound closure within 20 days. All these results strongly indicated that the PPIC hydrogel represented a tough and efficient platform for diabetic wound treatment.

Many anticancer drugs have limited clinical applications owing to their unsatisfactory therapeutic efficacy or side effects. This situation can be improved by drug delivery systems or drug modification strategies. Herein, to improve the therapeutic efficacy and safety of the traditional anticancer drug 6-mercaptopurine (6-MP), we dimerized 6-MP to form a disulfide bond-containing drug dimer and prepared a cysteine-based poly (disulfide amide) with redox-responsive capability as a drug carrier. Briefly, dimeric 6-MP (DMP) was synthesized via the oxidization of iodine and self-assembled with the poly (disulfide amide) to form dual redox-responsive DMP-loaded NPs (DMP-NPs). The 6-MP itself could hardly be loaded into nanoparticles (NPs) owing to its hydrophobicity, while the DMP-NPs showed a higher drug loading capacity over 6-MP, small particle size, and favorable stability. With abundant disulfide bonds in polymer backbones and drug payloads, DMP-NPs could rapidly respond to high levels of glutathione (GSH) and release drugs in a controllable manner. More importantly, both cellular and animal experiments demonstrated the enhanced anticancer efficacy of DMP-NPs against lymphoma and their high safety. Overall, this drug dimer-loaded dual redox-responsive drug delivery system provides new options for improving the applications of traditional drugs and developing drug delivery systems with enhanced drug effects and high safety.

Lung diseases, including COVID-19 and lung cancers, is a huge threat to human health. However, for the treatment and diagnosis of various lung diseases, such as pneumonia, asthma, cancer, and pulmonary tuberculosis, are becoming increasingly challenging. Currently, several types of treatments and/or diagnostic methods are used to treat lung diseases; however, the occurrence of adverse reactions to chemotherapy, drug-resistant bacteria, side effects that can be significantly toxic, and poor drug delivery necessitates the development of more promising treatments. Nanotechnology, as an emerging technology, has been extensively studied in medicine. Several studies have shown that nano-delivery systems can significantly enhance the targeting of drug delivery. When compared to traditional delivery methods, several nanoparticle delivery strategies are used to improve the detection methods and drug treatment efficacy. Transporting nanoparticles to the lungs, loading appropriate therapeutic drugs, and the incorporation of intelligent functions to overcome various lung barriers have broad prospects as they can aid in locating target tissues and can enhance the therapeutic effect while minimizing systemic side effects. In addition, as a new and highly contagious respiratory infection disease, COVID-19 is spreading worldwide. However, there is no specific drug for COVID-19. Clinical trials are being conducted in several countries to develop antiviral drugs or vaccines. In recent years, nanotechnology has provided a feasible platform for improving the diagnosis and treatment of diseases, nanotechnology-based strategies may have broad prospects in the diagnosis and treatment of COVID-19. This article reviews the latest developments in nanotechnology drug delivery strategies in the lungs in recent years and studies the clinical application value of nanomedicine in the drug delivery strategy pertaining to the lung.

Recently, tissue engineering has developed into a powerful tool for repairing and reconstructing damaged tissues and organs. Tissue engineering scaffolds play a vital role in tissue engineering, as they not only provide structural support for targeted cells but also serve as templates that guide tissue regeneration and control the tissue structure. Over the past few years, owing to unique physicochemical properties and excellent biocompatibility, various types of two-dimensional (2D) nanomaterials have been developed as candidates for the construction of tissue engineering scaffolds, enabling remarkable achievements in bone repair, wound healing, neural regeneration, and cardiac tissue engineering. These efforts have significantly advanced the development of tissue engineering. In this review, we summarize the latest advancements in the application of 2D nanomaterials in tissue engineering. First, each typical 2D nanomaterial is introduced briefly, followed by a detailed description of its applications in tissue engineering. Finally, the existing challenges and prospects for the future of the application of 2D nanomaterials in tissue engineering are discussed.