Preparation and properties of a 3D printed nHA/PLA bone tissue engineering scaffold loaded with a ß-CD-CHX combined dECM hydrogel.

Jaw defects, which can result from a multitude of causes, significantly affect the physical well-being and psychological health of patients. The repair of these infected defects presents a formidable challenge in the clinical and research fields, owing to their intricate and diverse nature. This study aims to develop a personalized bone tissue engineering scaffold that synergistically offers antibacterial and osteogenic properties for treating infected maxillary defects. This study engineered a novel temperature-sensitive, sustained-release hydrogel by amalgamating ß-cyclodextrin (ß-CD) with chlorhexidine (CHX) and a decellularized extracellular matrix (dECM). This hydrogel was further integrated with a polylactic acid (PLA)-nano hydroxyapatite (nHA) scaffold, fabricated through 3D printing, to form a multifaceted composite scaffold (nHA/PLA/dECM/ß-CD-CHX). Drug release assays revealed that this composite scaffold ensures prolonged and sustained release. Bacteriological studies confirmed that the ß-CD-CHX loaded scaffold exhibits persistent antibacterial efficacy, thus effectively inhibiting bacterial growth. Moreover, the scaffold demonstrated robust mechanical strength. Cellular assays validated its superior biocompatibility, attributed to dECM and nHA components, significantly enhancing the proliferation, adhesion, and osteogenic differentiation of osteogenic precursor cells (MC3T3-E1). Consequently, the nHA/PLA/dECM/ß-CD-CHX composite scaffold, synthesized via 3D printing technology, shows promise in inducing bone regeneration, preventing infection, and facilitating the repair of jaw defects, positioning itself as a potential breakthrough in bone tissue engineering.

Chitosan-vancomycin hydrogel incorporated bone repair scaffold based on staggered orthogonal structure: a viable dually controlled drug delivery system.

In clinical practice, challenges remain in the treatment of large infected bone defects. Bone tissue engineering scaffolds with good mechanical properties and antibiotic-controlled release are powerful strategies for infection treatment. In this study, we prepared polylactic acid (PLA)/nano-hydroxyapatite (nHA) scaffolds with vertical orthogonal and staggered orthogonal structures by applying 3D printing technology. In addition, vancomycin (Van)-based chitosan (CS) hydrogel (Gel@Van) was loaded on the scaffold (PLA/nHA/CS-Van) to form a local antibiotic release system. The microstructure of the composite scaffold had high porosity with interconnected three-dimensional networks. The mechanical properties of the PLA/nHA/CS-Van composite scaffold were enhanced by the addition of CS-Van. The results of the water contact angle analysis showed that the hydrophilicity of the drug-loaded scaffold improved. In addition, the composite scaffold could produce sustained release in vitro for more than 8 weeks without adverse effects on the proliferation and differentiation of mouse embryonic osteoblasts (MC3T3-E1), which confirmed its good biocompatibility. During the in vitro antimicrobial study, the composite scaffold effectively inhibited the growth of Staphylococcus aureus (S. aureus). Therefore, our results suggest that the PLA/nHA/CS-Van composite scaffold is a promising strategy for treating infected bone defects.

Atomic layer deposition of Pt nanoparticles onto Co/MoN nanoarrays for improved electrochemical detection of H2O2.

The design and preparation of advanced nanocatalysts for the sensitive electrochemical detection of H2O2 is of great significance. Herein, a facile Pt@Co/MoN sensing platform was fabricated by depositing Pt nanoparticles onto Co/MoN nanoarrays using atomic layer deposition (ALD) technology. Benefitting from the unique nanostructure and the strong interaction between Pt and the nitride support, the prepared Pt@Co/MoN exhibited excellent performance in the electrochemical detection of H2O2. This work provides an interesting strategy to fabricate low-Pt electrocatalysts on a nanoarray support for future applications in electroanalysis.

Improvement of the mechanical properties and osteogenic activity of 3D-printed polylactic acid porous scaffolds by nano-hydroxyapatite and nano-magnesium oxide.

Porous bone scaffolds based on high-precision 3D printing technology gave recently been developed for use in bone defect repair. However, conventional scaffold materials have poor mechanical properties and low osteogenic activity, limiting their clinical use. In this study, a porous composite tissue-engineered bone scaffold was prepared using polylactic acid, nano-hydroxyapatite, and nano-magnesium oxide as raw materials for high-precision 3D printing. The composite scaffold takes full advantage of the personalized manufacturing features of 3D printers and can be used to repair complex bone defects in clinical settings. The composite scaffold combines the advantages of nano-hydroxyapatite, which improves the formability of scaffold printing, and of nano-magnesium oxide, which regulates pH during degradation and provide a good environment for cell growth. Additionally, nano-magnesium oxide and nano-hydroxyapatite have a bidirectional effect on promoting the compressive strength and osteogenic activity of the scaffolds. The prepared composite porous scaffolds based on 3D printing technology show promise for bone defect repair.

Preparation and Characterization of Vancomycin Hydrochloride-Loaded Mesoporous Silica Composite Hydrogels.

This study aims to explore the feasibility of the novel temperature-sensitive hydrogel-based dual sustained-release system (Van/SBA-15/CS-GP-SA) in the repair and treatment of infectious jaw defects. Van/SBA-15 was prepared using the mesoporous silica (SBA-15) as a carrier for vancomycin hydrochloride (Van), and Van/SBA-15 was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectrometry (EDS), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR), Brunauer-Emmett-Teller (BET), and Barrett-Joyner-Halenda (BJH). The characterization results confirm that Van is loaded in SBA-15 successfully. Van/SBA-15/CS-GP-SA is constructed by encapsulating Van/SBA-15 in chitosan-sodium glycerophosphate-sodium alginate hydrogel (CS-GP-SA). The microstructures, sustained-release ability, biocompatibility, and antibacterial properties of Van/SBA-15/CS-GP-SA were systematically studied. Van/SBA-15/CS-GP-SA is found to have promising sustained-release ability, outstanding biocompatibility, and excellent antibacterial properties. This study provides new ideas for the management of infectious jaw defects.