An electrostatically crosslinked chitosan hydrogel as a drug carrier

Area of Science:

• Biomaterials Science
• Drug Delivery Systems
• Polymer Chemistry

Background:

• Controlling protein release is crucial for therapeutic applications.
• Hydrogels offer potential as drug depots due to their biocompatibility and tunable properties.
• Chitosan and glycerol phosphate disodium salt (GP) are biocompatible polymers with potential for hydrogel formation.

Purpose of the Study:

• To investigate the potential of chitosan/GP hydrogels as depots for sustained protein drug release.
• To characterize the formation and properties of chitosan/GP hydrogels.
• To evaluate the in vitro release profile of bovine serum albumin-fluorescein isothiocyanate (BSA-FITC) from these hydrogels.

Main Methods:

• Chitosan and GP solutions were mixed at varying concentrations (0-30 wt%) and temperatures (room temperature vs. 37°C).
• Electrostatic interactions and hydrogel formation were confirmed using zeta potential and particle size analysis.
• BSA-FITC was loaded into the hydrogels, and in vitro release studies were conducted over 14 days.

Main Results:

• Chitosan/GP solutions formed hydrogels at 37°C via electrostatic crosslinking between chitosan's amine groups and GP's phosphate groups.
• The electrostatic interaction strength was dependent on GP concentration and incubation time.
• BSA-FITC loaded hydrogels exhibited sustained release of BSA for up to 14 days in vitro.

Conclusions:

• Chitosan/GP hydrogels can be formed through electrostatic interactions at physiological temperatures.
• These hydrogels demonstrate potential as effective depots for sustained protein drug delivery.
• The developed hydrogel system offers a promising platform for controlled release of protein therapeutics like BSA.