"Stabilization" of Amorphous Ketoprofen in Thin Films.

Area of Science:

• Materials Science
• Pharmaceutical Science
• Physical Chemistry

Background:

• Amorphous solid dispersions are crucial for enhancing drug solubility and bioavailability.
• Ketoprofen, a non-steroidal anti-inflammatory drug, often requires stabilization in its amorphous form.
• Thin film deposition offers a method to control drug formulation and stability.

Purpose of the Study:

• To investigate the stabilization of amorphous ketoprofen in thin films.
• To evaluate the impact of polyethylene glycol (PEG) and relative humidity on ketoprofen's amorphous state.
• To understand the crystallization behavior of ketoprofen in amorphous thin films.

Main Methods:

• Preparation of amorphous ketoprofen/PEG thin films using spin coating.
• Characterization of film stability under varying relative humidity conditions.
• Analysis using specular X-ray diffraction and atomic force microscopy.

Main Results:

• Amorphous ketoprofen thin films remained stable for up to 4 months in dry conditions.
• Crystallization of ketoprofen was observed in films exposed to relative humidity >50%.
• Low ketoprofen concentrations and high humidity resulted in nanometer-sized crystals, with PEG's effect being concentration-dependent.

Conclusions:

• Thin film deposition stabilizes amorphous ketoprofen against crystallization in dry conditions.
• Humidity is a critical factor inducing crystallization in amorphous ketoprofen films.
• The presence and concentration of polyethylene glycol can modulate the crystallization kinetics of ketoprofen in amorphous films.