Applicability of non-halogenated methyl propionate to microencapsulation

Area of Science:

• Materials Science
• Chemical Engineering
• Pharmaceutical Technology

Background:

• Poly-lactic-co-glycolic acid (PLGA) microspheres are widely used for drug delivery.
• Ethyl acetate is a common solvent in PLGA microencapsulation, but alternatives are sought.
• Evaluating new solvents is crucial for optimizing microencapsulation processes.

Purpose of the Study:

• To assess the suitability of methyl propionate as a solvent for progesterone microencapsulation.
• To develop and characterize progesterone-loaded PLGA microspheres using methyl propionate.
• To compare the efficacy of methyl propionate with ethyl acetate in microencapsulation.

Main Methods:

• An emulsion-based microencapsulation technique was employed.
• Progesterone was encapsulated into PLGA microspheres using methyl propionate.
• Microsphere characteristics (size, span index, encapsulation efficiency, residual solvent) were analyzed.
• Comparison with microspheres prepared using ethyl acetate.

Main Results:

• Methyl propionate exhibited higher volatility and lower water miscibility than ethyl acetate.
• Well-formed microspheres were produced with an average diameter of 68.3 ± 1.7 μm and span index of 0.91 ± 0.13.
• Progesterone encapsulation efficiency ranged from 41.80% to 85.64%, with minimal polymorphic transition.
• Residual methyl propionate levels were low (0.97%–1.54%).

Conclusions:

• Methyl propionate is a promising solvent for PLGA microencapsulation.
• Microspheres produced with methyl propionate show comparable characteristics to those made with ethyl acetate.
• Methyl propionate offers a potential alternative solvent for pharmaceutical microencapsulation.