Chitosan-based nanoparticles as drug delivery systems for doxorubicin: Optimization and modelling

Area of Science:

• Biomaterials Science
• Drug Delivery Systems
• Nanotechnology

Background:

• Chitosan nanoparticles are widely explored for drug delivery due to their biocompatibility.
• Developing effective drug delivery systems for chemotherapeutics like doxorubicin is crucial for cancer treatment.
• Modifying chitosan, such as creating O-HTCC (ammonium-quaternary derivative of chitosan), can alter nanoparticle properties.

Purpose of the Study:

• To develop and characterize doxorubicin-loaded chitosan and O-HTCC nanoparticles.
• To investigate the doxorubicin release kinetics from these nanoparticles under different pH conditions.
• To evaluate the encapsulation efficiency and release mechanisms of the drug delivery systems.

Main Methods:

• Encapsulation of doxorubicin into chitosan and O-HTCC nanoparticles.
• Measurement of nanoparticle hydrodynamic diameter.
• In vitro doxorubicin release studies at acidic (pH 4.5) and physiological (pH 7.4) pH.
• Mathematical modeling of drug release kinetics.

Main Results:

• Nanoparticles with diameters below 200nm achieved high doxorubicin encapsulation (up to 70% for chitosan, 50% for O-HTCC).
• Doxorubicin release was significantly higher at acidic pH compared to physiological pH and was independent of chitosan molecular weight.
• O-HTCC nanoparticles exhibited a higher release rate than chitosan nanoparticles, with a burst release in the initial hours followed by a plateau after 24 hours.

Conclusions:

• Both chitosan and O-HTCC nanoparticles are effective systems for doxorubicin encapsulation and delivery.
• The acidic environment enhances doxorubicin release, suggesting potential for targeted delivery in tumor microenvironments.
• The release mechanism is primarily anomalous or mixed, consistent with chitosan's swelling behavior, and is influenced by pH.