Preparation of epigallocatechin gallate-loaded nanoparticles and characterization of their inhibitory effects onHelicobacter pylorigrowthin vitroandin vivo

Abstract

A variety of approaches have been proposed for overcoming the unpleasant side effects associated with antibiotics treatment of Helicobacter pylori (H. pylori) infections. Research has shown that epigallocatechin-3-gallate (EGCG), a major ingredient in green tea, has antibacterial activity for antiurease activity against H. pylori. Oral EGCG is not good because of its digestive instability and the fact that it often cannot reach the targeted site of antibacterial activity. To localize EGCG to H. pylori infection site, this study developed a fucose–chitosan/gelatin nanoparticle to encapsulate EGCG at the target and make direct contact with the region of microorganisms on the gastric epithelium. Analysis of a simulated gastrointestinal medium indicated that the proposed in vitro nanocarrier system effectively controls the release of EGCG, which interacts directly with the intercellular space at the site of H. pylori infection. Meanwhile, results of in vivo clearance assays indicated that our prepared fucose–chitosan/gelatin/EGCG nanoparticles had a significantly greater H. pylori clearance effect and more effectively reduced H. pylori-associated gastric inflammation in the gastric-infected mouse model than the EGCG solution alone.

Silver‐based wound dressings reduce bacterial burden and promote wound healing

“…Histologic analysis on day 3 was carried out using light microscopy. Briefly, biopsies were fixed in buffered paraformaldehyde and embedded in paraffin wax . Sections of 5 µm were stained with Masson's trichrome.…”

Development of chitosan/poly‐γ‐glutamic acid/pluronic/curcumin nanoparticles in chitosan dressings for wound regeneration

“…The nanoparticle suspension was placed onto a 400 mesh copper grid coated with carbon. About 2 min after deposition, the grid was tapped with a filter article to remove surface water and positively stained with an alkaline bismuth solution …”

“…About 2 min after deposition, the grid was tapped with a filter article to remove surface water and positively stained with an alkaline bismuth solution. 27 Preparation and characterization of chitosan/g-PGA/ pluronic/curcumin nanoparticles and incorporation into chitosan dressing Nanoparticles were incorporated into chitosan dressing using a freeze-drying process. Briefly, chitosan solution was prepared by dissolving chitosan (40.0 mg mL 21 , 20.0 mL) in 1.0% acetic acid, and the pH of the solution was adjusted to 6.0 by dialysis against distilled water for 24 h. Dialyzed solutions were then filtered and diluted in deionized water to prepare 10.0 mg mL 21 chitosan solutions.…”

Poly-γ-glutamic acid microneedles with a supporting structure design as a potential tool for transdermal delivery of insulin

“…To visualize the penetration of the FITC-insulin within the rat skin, the MN treated skin was excised and observed using a confocal laser scanning microscope (CLSM; FluoView FV1000, Olympus Corporation, Tokyo, Japan) at an excitation wavelength of 488 nm [34]. Images were obtained in the xy-plane.…”