Design and characterization of chitosan-based composite particles with tunable interfacial properties

Area of Science:

• Materials Science
• Polymer Chemistry
• Nanotechnology

Background:

• Chitosan and its derivatives are biocompatible polymers with diverse applications.
• Controlling particle size and stability is crucial for effective material formulation.

Purpose of the Study:

• To synthesize and characterize composite nano-microparticles (NMPs) using chitosan or carboxymethyl chitosan.
• To investigate the effect of aqueous solution conditions, specifically urea concentration, on NMP size.
• To assess the stability of the prepared NMPs.

Main Methods:

• Preparation of NMPs in aqueous solution using chitosan or carboxymethyl chitosan with polyanions (alginate, tripolyphosphate).
• Characterization using Nuclear Magnetic Resonance (NMR) spectroscopy ((1)H/(31)P), Infrared (IR) spectroscopy, and Dynamic Light Scattering (DLS).
• Evaluation of particle size and polydispersity index (PDI) under varying urea concentrations.

Main Results:

• Composite nano-microparticles (NMPs) were successfully prepared.
• DLS measurements indicated an increase in particle size with increasing aqueous urea concentration.
• Chitosan-based particles ranged from 243.0 ± 1 nm (0.28 PDI) to 424 ± 14 nm (0.33 PDI).
• NMP stability was observed to be dependent on particle composition and solution conditions, lasting two weeks or more at different ionic strengths.

Conclusions:

• The study successfully demonstrates the preparation of tunable chitosan-based nano-microparticles (NMPs).
• Urea concentration in aqueous solution is a key factor influencing NMP size.
• The findings highlight the potential of these NMPs for applications requiring controlled particle characteristics and stability.