Development of oral drug delivery system using floating microspheres

Area of Science:

• Materials Science
• Pharmaceutical Sciences
• Chemical Engineering

Background:

• Developing novel drug delivery systems is crucial for improving therapeutic efficacy.
• Microspheres offer a versatile platform for encapsulating various active pharmaceutical ingredients.
• Hollow microspheres can enhance drug loading and control release kinetics.

Purpose of the Study:

• To prepare floating acrylic resin microspheres with an internal hollow structure.
• To investigate the effects of solvent composition and preparation parameters on microsphere yield and characteristics.
• To evaluate drug encapsulation and release behavior using different model drugs.

Main Methods:

• Solvent diffusion and evaporation method utilizing ethanol, isopropanol, and dichloromethane.
• Optimization of organic phase composition, including solvent mixing ratios (e.g., ethanol:isopropanol:dichloromethane at 8:2:5).
• Controlled introduction of the organic phase into an aqueous phase and optimization of rotation speed (250 rpm) and temperature (25°C).

Main Results:

• Microsphere yield was significantly improved by using a mixture of ethanol and isopropanol compared to ethanol alone.
• The optimal volume ratio for the organic phase was determined to be ethanol:isopropanol:dichloromethane (8:2:5).
• Direct introduction of the organic phase into the aqueous phase enhanced yield by preventing surface contact.
• Drug loading efficiency was lowest for drugs with low solubility in dichloromethane and high solubility in water/ethanol-isopropanol mixtures.
• Drug release profiles varied significantly based on drug solubility and physicochemical properties.

Conclusions:

• Floating hollow acrylic microspheres can be successfully prepared using a tailored solvent diffusion and evaporation method.
• Careful control over solvent composition, preparation parameters, and introduction technique is essential for optimizing microsphere production.
• The physicochemical properties of the drug significantly influence encapsulation efficiency and release kinetics, highlighting the system's potential for controlled drug delivery.