PEGylated Biodegradable Polyesters for PGSS Microparticles Formulation: Processability, Physical and Release...

Area of Science:

• Biomaterials Engineering
• Drug Delivery Systems
• Supercritical Fluid Technology

Background:

• Particles from Gas Saturated Solution (PGSS) is an emerging technique utilizing supercritical carbon dioxide (scCO2) for microparticle production, suitable for encapsulating sensitive biomolecules.
• Poly(lactide acid) (PLA) and poly(lactic-co-glycolic acid) (PLGA) are common polymers in PGSS, with properties tunable by additives like polyethylene glycol (PEG).

Purpose of the Study:

• To investigate the impact of biodegradable PEGylated di-block copolymers on microparticle characteristics and drug release using the PGSS method.
• To evaluate the processability and performance of novel copolymer formulations in scCO2.

Main Methods:

• Synthesis of mPEG5kDa-P(L)LA and mPEG5kDa-P(L)LGA copolymers with comparable molecular weights.
• Preparation of microparticles using PGSS with varying copolymer content (9% and 81%).
• Characterization of particle size, morphology, yield, and in vitro release of bovine serum albumin (BSA) as a model protein.

Main Results:

• PEGylated copolymers exhibited good processability within the PGSS technique without negatively impacting microparticle physical properties.
• The concentration of PEGylated copolymers directly influenced the drug release profile, with higher content accelerating BSA release.
• Microparticle formulations demonstrated controlled release characteristics influenced by copolymer composition.

Conclusions:

• The PGSS technique is effective for producing microparticles using PEGylated di-block copolymers.
• Mild operating conditions (low pressure and temperature) are feasible for this PGSS application.
• The incorporation of PEGylated copolymers offers a viable strategy for modulating drug release kinetics in microparticle-based delivery systems.