Inner Rotation of Pickering Janus Emulsions.
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ABSTRACT:
SUBMITTER: Raju RR
PROVIDER: S-EPMC8708173 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:Periodontitis (PD) as a chronic inflammatory disease instigated by periodontal pathogenic bacteria and mediated by the host immune response, resulting in the destruction of supporting periodontal tissue and tooth loss in adults. Constructing an injectable delivery system that allows for sustained drug release within periodontal pockets to continuously eliminate pathogenic bacteria, reduce periodontal inflammation, and promote periodontal tissue regeneration is an effective strategy for periodontitis treatment. Here, we explore the therapeutic potential and underlying mechanisms of curcumin-loaded Pickering emulsion (PE-CUR) in periodontitis treatment. The Pickering emulsion formulation offers an effective delivery system, enhancing curcumin's bioavailability and therapeutic efficacy. In vitro studies, we demonstrate that the PE-CUR exhibit excellent biocompatibility and anti-inflammatory property by elimination of reactive oxygen species (ROS). In addition, PE-CUR significantly eliminate key periodontal pathogens, including Porphyromonas gingivalis (P. gingivalis) and Staphylococcus aureus (S. aureus). In a rat model of periodontitis, PE-CUR significantly attenuates periodontal tissue inflammation and alveolar bone loss, indicating a protective effect against periodontal tissue destruction. Mechanistically, PE-CUR promotes the expression of anti-inflammatory factors and inhibits the release of pro-inflammatory factors by regulating macrophage polarization from M1 to M2 and modulating the MAPK and PI3K-AKT signaling pathway. Furthermore, PE-CUR decreases the formation of osteoclasts as well as stimulates the activation and differentiation of osteoblasts successively, thereby ameliorating the periodontal inflammation and promoting the alveolar bone regeneration. Overall, our findings elucidate the therapeutic mechanisms of PE-CUR in periodontitis, suggesting its potential as a promising treatment strategy warranting further clinical investigation.
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Project description:Xylan is a highly abundant plant-based biopolymer. Original xylans in plants are in an amorphous state, but deacetylated and low-branched xylan can form a crystalline structure with water molecules. The utilizations of xylan have been limited to bulk applications either with inconsistency and uncertainty or with extensive chemical derivatization due to the insufficient studies on its crystallization. The applications of xylan could be greatly broadened in advanced green materials if xylan crystals are effectively utilized. In this paper, we show a completely green production of nano-sized xylan crystals and propose their application in forming Pickering emulsions. The branches of xylan were regulated during the separation step to controllably induce the formation of xylan hydrate crystals. Xylan hydrate nanocrystals (XNCs) with a uniform size were successfully produced solely by a mild ultrasonic treatment. XNCs can be adsorbed onto oil-water interfaces at a high density to form highly stable Pickering emulsions. The emulsifying properties of XNCs were comparable to some synthetic emulsifiers and better than some other common biopolymer nanocrystals, demonstrating that XNCs have great potential in industrial emulsification.
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Project description:Pickering emulsions are increasingly applied in drug delivery, oil-water separation, composite materials preparation, and other fields. However, systematic studies on the stabilization of Pickering emulsions to satisfy the growing application demands in multiple fields with long-term conservation are rare. Compared to conventional solid nanoparticles, polyanion-modified hairy nanoparticles are more stable in practical environments and are investigated in this study. Poly (sodium p-styrenesulfonate) was grafted to a polystyrene (PS) core via a photoemulsion polymerization. A hairy nanoparticle bearing polyanions called poly (sodium p-styrenesulfonate) brush (PS@PSS) was synthesized. The size and uniformity of the Pickering emulsions stabilized by PS@PSS were investigated via a polarizing microscope. The stability of Pickering emulsions were optimized by adjusting critical factors like ultrasonic power and time, standing time, oil phases, salt concentration, and water:oil ratio. Results indicated that the Pickering emulsions could be stabilized by PS@PSS nanoparticles, which showed remarkable and adjustable partial wetting properties. It was found that the optimized conditions were ultrasonic power of 150 W, ultrasonic time of 3 min, salt concentration of 0.1 mM, oil phase of hexadecane, and water:oil ratio of 1:1. The formation and stability of Pickering emulsion are closely related to the hairy poly (sodium p-styrenesulfonate) brush layer on the nanoparticle surface.
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