Crystallization and dissolution behavior of naproxen/polyethylene glycol solid dispersions.

Area of Science:

• Materials Science
• Pharmaceutical Science
• Physical Chemistry

Background:

• Solid dispersions are crucial for enhancing drug solubility and bioavailability.
• Controlling the crystallization kinetics of active pharmaceutical ingredients (APIs) within solid dispersions is vital for predictable drug release.

Purpose of the Study:

• To investigate the crystallization kinetics of naproxen (NAP) in NAP/polyethylene glycol (NAP/PEG) solid dispersions.
• To correlate crystallization temperature with NAP domain size, microstructure, and subsequent dissolution behavior.

Main Methods:

• In situ small-angle X-ray scattering/wide-angle X-ray scattering (SAXS/WAXS) to study crystallization kinetics.
• Second-order nonlinear optical imaging of chiral crystals (SONICC) for surface area analysis and domain size determination.
• Dissolution testing of NAP/PEG solid dispersions prepared at varying temperatures (25 °C and 40 °C).

Main Results:

• Naproxen (NAP) crystallization rate was faster at 25 °C compared to 40 °C.
• NAP domains were smaller at 25 °C and larger at 40 °C, as confirmed by SONICC.
• Solid dispersions prepared at 25 °C exhibited faster dissolution rates than those prepared at 40 °C.
• Microstructure and dissolution were also influenced by the chemical composition of the solid dispersions.

Conclusions:

• Crystallization temperature significantly influences naproxen domain size and dissolution profiles in NAP/PEG solid dispersions.
• Optimizing crystallization temperature is essential for tailoring the performance of naproxen solid dispersions.
• The findings provide insights into the rational design of solid dispersions for improved drug delivery.