Drug encapsulation in alginate microspheres by emulsification.

Area of Science:

• Materials Science
• Pharmaceutical Technology

Background:

• Calcium alginate microspheres are utilized for drug delivery applications.
• Previous methods faced challenges with low drug encapsulation efficiency.

Purpose of the Study:

• To develop an effective method for producing calcium alginate microspheres with high drug encapsulation.
• To investigate factors influencing drug encapsulation efficiency.

Main Methods:

• Utilized an emulsification process for microsphere production.
• Investigated the impact of dehydrating solvents (isopropyl alcohol, acetone) on encapsulation.
• Explored phase inversion and drug particle suspension techniques.
• Varied the drug-to-encapsulating material ratio.

Main Results:

• Dehydrating solvents significantly reduced drug encapsulation due to drug solubility.
• High drug encapsulation was achieved by omitting solvents and employing phase inversion.
• A drug particle suspension was crucial for effective microencapsulation.
• Encapsulation efficiency increased with a higher drug-to-material ratio.

Conclusions:

• Optimized calcium alginate microsphere production by avoiding dehydrating solvents.
• Phase inversion and drug particle suspension are key for high drug loading.
• The developed method yields free-flowing microspheres, predominantly under 150 microns.