Enhanced osteogenic and bactericidal performance of premixed calcium phosphate cement with photocrosslinked alginate thin film.

The increasing prevalence of implant-associated infections (IAI) in orthopedics remains a public health challenge. Calcium phosphates (CaPs) are critical biomaterials in dental treatments and bone regeneration. It is highly desirable to endow CaPs with antibacterial properties.

Macroporous zwitterionic composite cryogel based on chitosan oligosaccharide for antifungal application.

Chitosan oligosaccharide (COS), a time-dependent antimicrobial carbohydrate, is found antifungal active with a short duration of action due to excessive solubility. We attempted to address this issue by employing a hydrogel as a COS carrier. In this research, macroporous zwitterionic composite cryogels composed of COS and poly(N-methacryl arginine) (PMarg) were fabricated, serving as long-term antifungal dressings.

A series of carboxymethyl cellulose-based antimicrobial peptide mimics were synthesized for antimicrobial applications.

Inspired by antimicrobial peptides (AMP) which could alleviate drug resistance pressure, antimicrobial peptide mimics (AMPMs) were designed timely. Here, carboxymethyl cellulose (CMC) -based AMPMs were constructed by introducing different diamines on CMC effectively. Firstly, CMC was degraded to be oligomers with different molecular weights, followed by amination reactions with different diamines respectively.

Osteogenic, Angiogenic, and Antibacterial Bioactive Nano-Hydroxyapatite Co-Synthesized Using γ-Polyglutamic Acid and Copper.

Nano-antibacterial calcium phosphate (CaP) has attracted intense attention with regard to its wide variety of medical and biological applications. The γ-polyglutamic acid and copper cosynthesized hydroxyapatite (γ-PGA/CuHAp) was synthesized using the wet method. Structural and chemical characterizations demonstrate that copper was quantitatively incorporated into the hydroxyapatite structure, and the degree of Cu substitution was up to 20 mol % in the synthesized nanocrystals.

Nanocopper-loaded Black phosphorus nanocomposites for efficient synergistic antibacterial application.

Novel nanocopper-loaded black phosphorus (BP/Cu) nanocomposites were synthesized to synergistically exert enhanced antibacterial activities aimed at reducing antibiotics abuse. First, both BP and Cu display low biotoxicity, broadening their application in the microbiological field. Second, the unique electronic properties of BP enable BP/Cu nanocomposites to amplify antibacterial effects via interfacial charge transfer, resulting in a surge of reactive oxygen species (ROS).

Complexation and conformation of lead ion with poly-γ-glutamic acid in soluble state.

Complexation of microbial polymer in soluble state could impact the solubility, mobility, and bioavailability of heavy metals in the environment. The complexation of a bacterial exopolymer, poly-γ-glutamic acid (γ-PGA), with Pb2+ was studied using the polarographic method and circular dichroism measurement in soluble state. The number of available binding sites was determined based on the Chau's method and was found to be 0.

Pyrolysis preparation of poly-γ-glutamic acid derived amorphous carbon nitride for supporting Ag and γ-FeO nanocomposites with catalytic and antibacterial activity.

Nanocomposites composed of Ag and γ-FeO nanoparticles within poly-γ-glutamic acid (γ-PGA) derived amorphous carbon nitride (a-CN) films (Ag + γ-FeO@a-CN) were synthesized by a one-step facile pyrolysis strategy. Transmission electron microscopy analysis shows that Ag and γ-FeO nanoparticles were obtained in situ and homogeneously dispersed on the a-CN matrix. The average size of nanoparticles was 8.

Hydrogen bonding impact on chitosan plasticization.

The use of chitosan natural polymers to replace synthetic polymers is of interest as part of the green materials movement. However, a major challenge of using chitosan material is its rigid and brittle nature associated primarily with its intra- and inter-molecular hydrogen bonds creating a hydrogen bond network. Plasticizers are able to make chitosan flexible, hypothetically by destroying its hydrogen bond networks.

Combined delivery of bone morphogenetic protein-2 and insulin-like growth factor-1 from nano-poly (γ-glutamic acid)/β-tricalcium phosphate-based calcium phosphate cement and its effect on bone regeneration in vitro.

In this study, nano-doped calcium phosphate cement delivery systems (poly (γ-glutamic acid)/β-tricalcium phosphate/calcium phosphate ceramics and nano (γ-glutamic acid)/β-tricalcium phosphate/calcium phosphate ceramic) were fabricated, and low doses (10 µg/g) of two growth factors, insulin-like growth factor-1 and bone morphogenetic protein-2, were encapsulated then sequentially released. We characterized the delivery systems using Fourier transform infrared spectroscopy and X-ray diffraction and measured washout resistance and compressive strength, and thus optimized the most appropriate proportioning of delivery systems for the two growth factors. One of the growth factors was absorbed by the nano-poly (γ-glutamic acid)/β-tricalcium phosphate, which was then mixed into the calcium phosphate ceramic solid phase to create a new solid phase calcium phosphate ceramic.

Poly (γ-glutamic acid)/beta-TCP nanocomposites via in situ copolymerization: Preparation and characterization.

A series biodegradable poly (γ-glutamic acid)/beta-tricalcium phosphate (γ-PGA/TCP) nanocomposites were prepared which were composed of poly-γ-glutamic acid polymerized in situ with β-tricalcium phosphate and physiochemically characterized as bone graft substitutes. The particle size via dynamic light scattering, the direct morphological characterization via transmission electron microscopy and field emission scanning electron microscope, which showed that γ-PGA and β-TCP were combined compactly at 80℃, and the γ-PGA/TCP nanocomposites had homogenous and nano-sized grains with narrow particle size distributions. The water uptake and retention abilities, in vitro degradation properties, cytotoxicity in the simulated medium, and protein release of these novel γ-PGA/TCP composites were investigated.