ACS Biomaterials Science & Engineering最新文献

Paclitaxel (PTX) is a widely used anticancer drug for ovarian cancer treatment, but its clinical application is limited by poor water solubility and dose-limiting toxicities. To overcome these challenges, we developed a thermoresponsive, multistep drug delivery system, pNIB/PTX, designed to improve PTX solubility and provide controlled drug release. The pNIB/PTX-3 complex exhibited an initial rapid drug release phase followed by sustained slow release, optimizing both short-term and long-term therapeutic efficacy. At physiological temperatures, the complex demonstrated a precisely controlled drug release mechanism driven by changes in the polymeric micelle structure. In vitro studies showed that pNIB/PTX-3 significantly enhanced therapeutic effects in human ovarian cancer cell lines HeyA8 and SKOV3ip1, compared to PTX alone. In orthotopic ovarian cancer mouse models, a single intraperitoneal injection of pNIB/PTX-3 led to a substantial reduction in tumor size and prolonged survival. This multistep, thermoresponsive delivery system shows strong potential as a promising therapeutic option for dose-dense ovarian cancer treatments, providing improved drug stability, controlled release, and minimized side effects.

Rapid rewarming is the standard and most common strategy for treating frostbite. Due to freezing susceptibility and lack of thermal effects, traditional therapeutic hydrogels are not suitable for being directly applied to frostbite therapy in cold conditions. Contrastively, antifreezing and photothermal hydrogels that are not apt to freeze and capable of rewarming frostbite wounds are deemed to hold great application potential in such therapy. Nevertheless, these hydrogels have rarely been researched. Herein, using glycerol as the cryoprotectant and polydopamine nanoparticles (PDA NPs) as the photothermal agent, a novel pullulan-based antifreezing and photothermal organohydrogel (CPG-PDA organohydrogel) was successfully developed to treat frostbite for the first time. The CPG-PDA organohydrogel formed through 1-ethyl-3-(3-(dimethylamino)propyl)carbodiimide hydrochloride (EDC·HCl)-mediated esterification reactions was found to possess certain mechanical stability, shear-thinning behaviors (injectability), excellent antifreezing properties, superb in vitro and in vivo photothermal performances, and outstanding cytocompatibility and hemocompatibility. Most noticeably, the photothermal rewarming and coating therapy using the CPG-PDA organohydrogel was observed to significantly accelerate the frostbite healing of rats. The CPG-PDA organohydrogel was opined to be a promising platform for the direct treatment of frostbite in a cold environment and would open a new avenue for the design of therapeutic strategies for frostbite.

Infected bone defects, caused by bacterial contamination following disease or injury, result in the partial loss or destruction of bone tissue. Traditional bone transplantation and other clinical approaches often fail to address the therapeutic complexities of these conditions effectively. In recent years, advanced biomaterials have attracted significant attention for their potential to enhance treatment outcomes. This review explores the pathogenic mechanisms underlying infected bone defects, including biofilm formation and bacterial internalization into bone cells, which allow bacteria to evade the host immune system. To control bacterial infection and facilitate bone repair, we focus on antibacterial materials for bone regeneration. A detailed introduction is given on intrinsically antibacterial materials (e.g., metal alloys, oxide materials, carbon-based materials, hydroxyapatite, chitosan, and Sericin). The antibacterial functionality of bone repair materials can be enhanced through strategies such as the incorporation of antimicrobial ions, surface modification, and the combined use of multiple materials to treat infected bone defects. Key innovations discussed include biomaterials that release therapeutic agents, functional contact biomaterials, and bioresponsive materials, which collectively enhance antibacterial efficacy. Research on the clinical translation of antimicrobial bone materials has also facilitated their practical application in infection prevention and bone healing. In conclusion, advancements in biomaterials provide promising pathways for developing more biocompatible, effective, and personalized therapies to reconstruct infected bone defects.

Infected bone defects, caused by bacterial contamination following disease or injury, result in the partial loss or destruction of bone tissue. Traditional bone transplantation and other clinical approaches often fail to address the therapeutic complexities of these conditions effectively. In recent years, advanced biomaterials have attracted significant attention for their potential to enhance treatment outcomes. This review explores the pathogenic mechanisms underlying infected bone defects, including biofilm formation and bacterial internalization into bone cells, which allow bacteria to evade the host immune system. To control bacterial infection and facilitate bone repair, we focus on antibacterial materials for bone regeneration. A detailed introduction is given on intrinsically antibacterial materials (e.g., metal alloys, oxide materials, carbon-based materials, hydroxyapatite, chitosan, and Sericin). The antibacterial functionality of bone repair materials can be enhanced through strategies such as the incorporation of antimicrobial ions, surface modification, and the combined use of multiple materials to treat infected bone defects. Key innovations discussed include biomaterials that release therapeutic agents, functional contact biomaterials, and bioresponsive materials, which collectively enhance antibacterial efficacy. Research on the clinical translation of antimicrobial bone materials has also facilitated their practical application in infection prevention and bone healing. In conclusion, advancements in biomaterials provide promising pathways for developing more biocompatible, effective, and personalized therapies to reconstruct infected bone defects.

Infected bone defects show a significant reduction in neovascularization during the healing process, primarily due to persistent bacterial infection and immune microenvironmental disorders. Existing treatments are difficult to simultaneously meet the requirements of antibacterial and anti-inflammatory treatments for infected bone defects, which is a key clinical therapeutic challenge that needs to be addressed. In this study, a conductive hydrogel based on copper nanoparticles was developed for controlling bacterial infection and remodeling the immune microenvironment. The hydrogel not only effectively eliminates bacteria that exist in the infected bone defect region but also transmits electrical signals to restore the disordered immune microenvironment. In vitro studies have shown that the hydrogel has excellent biocompatibility and can modulate macrophage polarization by transmitting electrical signals to reduce inflammation and promote neovascularization. In vivo studies further confirmed that the hydrogel scaffold not only rapidly cleared clinical bacterial infections but also significantly induced the formation of vascularized new bone tissue within 4 weeks. This work provides a simple and innovative strategy to fabricate copper-containing conductive hydrogels that show great potential for application in the field of therapeutics for infected bone regeneration.

Infected bone defects show a significant reduction in neovascularization during the healing process, primarily due to persistent bacterial infection and immune microenvironmental disorders. Existing treatments are difficult to simultaneously meet the requirements of antibacterial and anti-inflammatory treatments for infected bone defects, which is a key clinical therapeutic challenge that needs to be addressed. In this study, a conductive hydrogel based on copper nanoparticles was developed for controlling bacterial infection and remodeling the immune microenvironment. The hydrogel not only effectively eliminates bacteria that exist in the infected bone defect region but also transmits electrical signals to restore the disordered immune microenvironment. In vitro studies have shown that the hydrogel has excellent biocompatibility and can modulate macrophage polarization by transmitting electrical signals to reduce inflammation and promote neovascularization. In vivo studies further confirmed that the hydrogel scaffold not only rapidly cleared clinical bacterial infections but also significantly induced the formation of vascularized new bone tissue within 4 weeks. This work provides a simple and innovative strategy to fabricate copper-containing conductive hydrogels that show great potential for application in the field of therapeutics for infected bone regeneration.

Gadolinium functionalized carbon dot complexes (Gd-CDs) have both the fluorescent properties of carbon dots and the magnetic characteristics of gadolinium ions, exhibiting excellent biocompatibility, high spatial resolution, high sensitivity, and deep tissue penetration in bioimaging. As fluorescence (FL) and magnetic resonance imaging (MRI) probes, Gd-CDs have attracted significant attention in dual-modal biological imaging. This review summarizes recent advances in Gd-CDs, focusing on their structure, optical and magnetic properties, and applications in dual-modal imaging. First, according to the different existing forms of gadolinium in carbon dots, the structures of Gd-CDs are categorized into chelation, electrostatic interaction, and encapsulation. Second, the mechanisms and performances of Gd-CDs in dual-modal imaging are introduced in detail. The reported Gd-CDs have a maximum quantum yield of 69.86%, with a fluorescence emission wavelength reaching up to 625 nm, and the optimum longitudinal and transverse relaxivity rates are 35.39 and 115.6 mM^–1 s^–1, respectively, showing excellent FL/MRI capacities. Subsequently, the progress in their applications in dual-modal cellular imaging, in vivo imaging, and integrated cancer diagnosis and therapy is reviewed. Finally, the challenges and issues faced by Gd-CDs in their development are summarized, providing new insights for their controlled synthesis and widespread application in the biomedical field of dual-modal imaging.

Gadolinium functionalized carbon dot complexes (Gd-CDs) have both the fluorescent properties of carbon dots and the magnetic characteristics of gadolinium ions, exhibiting excellent biocompatibility, high spatial resolution, high sensitivity, and deep tissue penetration in bioimaging. As fluorescence (FL) and magnetic resonance imaging (MRI) probes, Gd-CDs have attracted significant attention in dual-modal biological imaging. This review summarizes recent advances in Gd-CDs, focusing on their structure, optical and magnetic properties, and applications in dual-modal imaging. First, according to the different existing forms of gadolinium in carbon dots, the structures of Gd-CDs are categorized into chelation, electrostatic interaction, and encapsulation. Second, the mechanisms and performances of Gd-CDs in dual-modal imaging are introduced in detail. The reported Gd-CDs have a maximum quantum yield of 69.86%, with a fluorescence emission wavelength reaching up to 625 nm, and the optimum longitudinal and transverse relaxivity rates are 35.39 and 115.6 mM^-1 s^-1, respectively, showing excellent FL/MRI capacities. Subsequently, the progress in their applications in dual-modal cellular imaging, in vivo imaging, and integrated cancer diagnosis and therapy is reviewed. Finally, the challenges and issues faced by Gd-CDs in their development are summarized, providing new insights for their controlled synthesis and widespread application in the biomedical field of dual-modal imaging.