Synthesis and characterisation of polynorepinephrine-shelled microcapsules via an oil-in-water emulsion templating route

J Mater Chem B. 2021 Dec 1;9(46):9575-9582. doi: 10.1039/d1tb01786a.

Abstract

In this article, we present a facile and robust method for the surfactant-free preparation of polynorepinephrine stabilised microcapsules templated from an oil-in-water emulsion. The resulting microcapsule structures are dependent on the concentration of Cu2+ used to catalyse norepinephrine polymerisation. When the concentration of Cu2+ increases, the diameter of the microcapsules and the thickness of the shell increase correspondingly. The mechanical and chemical stability provided by the polynorepinephrine shell are explored using surface pressure measurements and atomic force microscopy, demonstrating that a rigid and robust polynorepinephrine shell is formed. In order to demonstrate potential application of the microcapsules in sustained release, Nile red stained squalane was encapsulated, and pH responsive release was monitored. It was seen that by controlling pH, the release profile could be controlled, with highest release efficacy achieved in alkaline conditions, offering a new pathway for development of encapsulation systems for the delivery of water insoluble actives.

MeSH terms

  • Anti-Bacterial Agents / chemical synthesis
  • Anti-Bacterial Agents / pharmacology
  • Antineoplastic Agents / administration & dosage
  • Antineoplastic Agents / therapeutic use
  • Capsules / chemical synthesis
  • Cell Line, Tumor
  • Drug Delivery Systems
  • Emulsions / chemistry
  • Escherichia coli / drug effects
  • Humans
  • Hydrogels / chemical synthesis
  • Hydrogen-Ion Concentration
  • Nanocomposites / chemistry*
  • Neoplasm Recurrence, Local / drug therapy
  • Norepinephrine / chemistry*
  • Polyethylene Glycols / chemistry
  • Skin Neoplasms
  • Staphylococcus aureus / drug effects
  • Tissue Engineering
  • Wound Healing

Substances

  • Anti-Bacterial Agents
  • Antineoplastic Agents
  • Capsules
  • Emulsions
  • Hydrogels
  • Polyethylene Glycols
  • Norepinephrine