Controlled delivery achieved with bi-layer matrix devices produced by co-injection moulding

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Pharmaceutical Technology

Background:

• Single-layer matrix systems often exhibit non-linear drug release kinetics.
• Soy protein offers potential as a biocompatible material for drug delivery systems.
• Controlled drug delivery aims to optimize therapeutic efficacy and patient compliance.

Purpose of the Study:

• To design and evaluate novel soy protein-based bi-layered matrix systems for controlled drug delivery.
• To investigate the influence of system design (skin thickness, crosslinking) on drug release profiles.
• To explore the pH-dependent drug release behavior of these soy protein matrices.

Main Methods:

• Co-injection molding of bi-layered matrix systems with a drug-free outer layer and a drug-containing core.
• Characterization of drug release kinetics at different pH values (5.0 and 7.4).
• Analysis of the effect of skin thickness and core crosslinking on release patterns.
• Scanning electron microscopy (SEM) for morphological analysis.

Main Results:

• Bi-layered systems showed significantly reduced drug release rates compared to single-layer systems.
• Skin thickness and core crosslinking were identified as key parameters for tailoring release.
• The soy protein matrices exhibited distinct pH-dependent behavior, with higher solubility and release at pH 7.4.
• A switch from pH 5.0 to pH 7.4 induced an abrupt increase in drug release, demonstrating a slow/fast release profile.

Conclusions:

• Soy protein-based bi-layered systems are effective for achieving controlled and tunable drug delivery.
• The pH-dependent nature of soy protein allows for the development of sophisticated release profiles.
• These findings support the creation of pre-programmed drug release systems and multi-layered devices with bimodal release patterns.