Dual responsive copolymer micelles for drug controlled release

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Drug Delivery Systems

Background:

• Development of advanced drug delivery systems is crucial for targeted and controlled therapeutic agent release.
• Chitosan oligosaccharide (CSO) and Pluronic copolymers offer unique properties for creating stimuli-responsive materials.
• Controlled release of chemotherapeutic agents like Doxorubicin (DOX) can improve efficacy and reduce side effects.

Purpose of the Study:

• To synthesize and characterize novel pH- and temperature-responsive polymeric drug carriers based on CSO-g-Pluronic copolymers.
• To evaluate the potential of these copolymers for controlled Doxorubicin (DOX) release.
• To investigate the stimuli-responsive behavior (pH and temperature) of the synthesized drug carriers.

Main Methods:

• Synthesis of Chitosan oligosaccharide (CSO)-g-Pluronic copolymers.
• Characterization of copolymer properties including critical aggregation concentration (CAC) and hydrodynamic diameter using dynamic light scattering.
• Assessment of Doxorubicin (DOX) loading and release kinetics under varying temperature and pH conditions using fluorescence spectroscopy and zeta potential analysis.

Main Results:

• CSO-g-Pluronic copolymers were successfully synthesized, forming micelles with an average hydrodynamic diameter of 23.3 nm at 30°C and pH 7.0.
• DOX-loaded micelles exhibited a larger average diameter (43.6 nm) and demonstrated temperature-dependent transformation due to Pluronic segment dehydration at higher temperatures.
• pH-responsive behavior was observed, with increased micellar volume at acidic conditions due to CSO segment protonation, leading to prolonged DOX release at 37°C and accelerated release at tumor-like acidic pH.

Conclusions:

• The synthesized CSO-g-Pluronic copolymers effectively form stimuli-responsive micelles for controlled Doxorubicin delivery.
• The copolymers exhibit significant temperature and pH sensitivity, enabling tunable drug release profiles.
• These findings highlight the promising potential of CSO-g-Pluronic copolymers for advanced biomedical and biotechnological drug delivery applications.