Novel Polyurethane Matrix Systems Reveal a Particular Sustained Release Behavior Studied by Imaging and Computational...

Area of Science:

• Materials Science
• Pharmaceutical Sciences
• Computational Chemistry

Background:

• Sustained drug release formulations are critical for therapeutic efficacy.
• Understanding drug release mechanisms from novel polymer matrices is essential.
• Polyurethanes offer potential for advanced drug delivery systems.

Purpose of the Study:

• To elucidate the drug release mechanism from sustained-release matrices formulated with novel polyurethanes.
• To evaluate a new in silico (computer simulation) tool for predicting drug release.
• To compare in silico predictions with experimental drug release data.

Main Methods:

• Preparation of binary matrix tablets using two new polyurethanes and theophylline as a model drug.
• In silico simulation of drug release using a 3D cellular automata model.
• Experimental drug release studies.
• Scanning electron microscopy (SEM) for imaging polymer distribution and tortuosity.

Main Results:

• The novel polyurethanes demonstrated significant control over drug release, even at low concentrations (10% w/w excipient controlled release for ~8 hours).
• The in silico model accurately predicted experimental drug release profiles.
• SEM imaging revealed a specific geometrical arrangement of excipient particles forming a drug-encircling barrier.

Conclusions:

• The novel polyurethanes provide effective sustained drug release through a unique geometrical excipient barrier mechanism.
• The mesoscopic in silico model is a valuable tool for understanding and predicting drug release from such matrices.
• These polyurethanes offer advantages over traditional lipid/waxy excipients, including better compactability, stability, and no polymorphism.