PLGA-based monolithic filaments prepared by hot-melt extrusion: In-vitro comparative study

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Pharmaceutical Technology

Background:

• Frequent drug administration necessitates advanced drug delivery systems.
• Poly(lactic-co-glycolic acid) (PLGA) is a versatile biodegradable polymer for controlled drug release.
• Filament-shaped implants offer a monolithic approach for sustained drug delivery.

Purpose of the Study:

• To investigate the impact of formulation variables on PLGA-based filament implants.
• To evaluate the influence of PLGA type, drug properties, and drug loading on drug release kinetics and material characteristics.
• To demonstrate the potential for tailoring PLGA implant properties for controlled drug delivery.

Main Methods:

• Preparation of PLGA-based monolithic filament implants using hot-melt extrusion (HME).
• Formulation variables included PLGA type (PLGA 502, PLGA 503), drug type (Prednisolone acetate, Propranolol Hydrochloride), and drug loading (10%, 30%).
• Characterization involved SEM, DSC, water uptake, mass loss, erosion, mechanical testing, and drug release studies.

Main Results:

• PLGA 503 implants exhibited lower water uptake, reduced erosion, slower drug release, and superior mechanical properties compared to PLGA 502 implants.
• Hydrophilic Propranolol Hydrochloride (PH) loaded implants showed faster swelling, degradation, and drug release (approx. 18 days) than lipophilic Prednisolone acetate (PA) implants (approx. 30 days).
• All formulations demonstrated zero-order release kinetics, indicating suitability for controlled drug delivery.

Conclusions:

• PLGA type, drug hydrophilicity, and drug loading are critical factors in tailoring PLGA implant properties.
• Hot-melt extrusion is an effective method for preparing customized PLGA implants for controlled drug release.
• These findings highlight the potential for developing patient-specific drug delivery systems using PLGA-based implants.