Yuji Pu

We developed a multifunctional injectable PEG hydrogel incorporating gold nanorods and a DNA nanostructure-mediated silver delivery system (AR@A-C@Ag/Gel) for synergistic antibacterial therapy and infected wound repair.

The development of oral drug delivery systems with colon-targeted release and high biocompatibility is of critical importance for the treatment of ulcerative colitis (UC), considering the chronic nature of the disease and the genetic susceptibility of patients. Herein, we report a composite delivery system (UA@PB/Gel) based on Generally Recognized As Safe (GRAS) materials, poly(vinyl alcohol) (PVA) and inulin, designed for colon-specific delivery of ursolic acid (UA). In this system, butyrate-conjugated PVA nanoparticles efficiently encapsulate UA and respond to colonic esterase, enabling the localized release of both UA and butyrate. Embedding these nanoparticles within an inulin hydrogel further enhances colonic retention and provides a sustained release. The composite system demonstrates efficient colon-targeting delivery, prolonged retention, and potent anti-inflammatory effects in vitro and in vivo. In a dextran sulfate sodium-induced colitis mouse model, UA@PB/Gel effectively alleviates colonic inflammation, restores epithelial barrier integrity, reduces proinflammatory cytokine expression, and modulates gut short-chain fatty acid levels, with minimal systemic toxicity. These results highlight the potential of the GRAS materials-based nanoparticle-hydrogel composite as a safe and effective therapeutic platform for UC.

A nanoparticle–hydrogel composite system was engineered to enhance the colonic delivery and oral bioavailability of baicalein, exhibiting synergistic anti-inflammatory effects with EGCG in a murine colitis model.

The gut's inflammation is governed by the enteric nervous system, where enteric glial cells (EGCs) serve as essential intermediaries between the nervous and immune systems. During inflammation, elevated levels of S100 calcium-binding protein B (S100B) from hyperactive EGCs initiate a proinflammatory cascade by inducing the excessive production of reactive oxygen species (ROS) and proinflammatory molecules, including S100B itself, thus establishing a detrimental feedback loop. Herein, we develop a S100B inhibitor pentamidine (PTM)-loaded olsalazine-based nanoneedle, Zn₂(Olsa)/PTM, to break this vicious cycle and alleviate ulcerative colitis. Zn₂(Olsa)/PTM not only enhances the cytocompatibility of PTM but also reduces the level of excessive production of S100B and ROS in EGCs. To enhance colon-targeted delivery, Zn₂(Olsa)/PTM is coated with an enteric polymer Eudragit L100-55 to create ZOP@Eud. The oral administration of ZOP@Eud considerably ameliorates disease severity and restores mucosal barrier integrity and immune homeostasis in a murine ulcerative colitis model, which is evidenced by heightened expression of tight junction proteins and reduced levels of colonic proinflammatory S100B and cytokines. These findings suggest that nanosystems targeting EGCs offer a promising approach for mitigating gut inflammation.

The hierarchical structure of bioactive glass fiber-reinforced PCL- b -PLLA diblock copolymer composites with antibacterial and osteogenic properties as well as high mechanical performance.

Hemostasis is the initial step in wound healing, yet significant challenges, such as massive bleeding and infection, often arise. In this study, we developed amphiphilic biodegradable polyester-based segmented polyurethane (SPU) microspheres modified with epigallocatechin gallate (EGCG)-Ag nanoparticles and calcium-alginate cross-linking shell, combining blood absorption with the pro-coagulation properties of Ca²⁺ and the negative charge of EGCG for synergistic hemostatic effects across various stages of the coagulation cascade. The in vitro blood clotting time of the SPU@EAg@CaAlg microsphere (328.7 s) was reduced by half compared to the SPU microsphere (685.0 s). SPU@EAg@CaAlg exhibited a reduced hemostatic time and blood loss in three rat hemostatic models. Additionally, EGCG-Ag nanoparticles imparted strong antibacterial and anti-inflammatory properties both in vitro and in vivo. In vivo infected wound model demonstrated that SPU@EAg@CaAlg effectively eliminated bacteria and reduced the levels of pro-inflammatory factors, thereby promoting wound healing. Thus, the modified SPU microspheres present a promising candidate for effective hemostatic applications.