Core-shell chitosan/Porphyridium-exopolysaccharide microgels: Synthesis, properties, and biological evaluation

Int J Biol Macromol. 2023 Aug 15:246:125655. doi: 10.1016/j.ijbiomac.2023.125655. Epub 2023 Jul 1.

Abstract

Advanced materials used in the biomedicine field comprises a diverse group of organic molecules, including polymers, polysaccharides, and proteins. A significant trend in this area is the design of new micro/nano gels whose small size, physical stability, biocompatibility, and bioactivity could lead to new applications. Herein a new synthesis route is described to obtain core-shell microgels based on chitosan and Porphyridium exopolysaccharides (EPS) crosslinked with sodium tripolyphosphate (TPP). First, the synthesis of EPS-chitosan gels through ionic interactions was explored, leading to the formation of unstable gels. Alternatively, the use of TTP as crosslinker agent led to stable core-shell structures. The influence of reaction temperature, sonication time, and exopolysaccharide concentration, pH and TPP concentration were determined as a function of particle size and polydispersity index (PDI). The obtained EPS-chitosan gels were characterized by TEM, TGA, and FTIR; followed by the assessment of protein load capacity, stability upon freezing, cytotoxicity, and mucoadhesivity. Experimentation revealed that the core-shell particles size ranges 100-300 nm, have a 52 % loading capacity for BSA and a < 90 % mucoadhesivity, and no toxic effects in mammalian cell cultures. The potential application of the obtained microgels in the biomedical field is discussed.

Keywords: Core-shell; Exopolysaccharides; Hydrogel; Porphyridium.

MeSH terms

  • Animals
  • Chitosan* / chemistry
  • Gels / chemistry
  • Ions
  • Mammals
  • Microgels*
  • Particle Size
  • Porphyridium*

Substances

  • Chitosan
  • Microgels
  • Gels
  • Ions