[Biodegradable microparticles with immobilized peptide for wound healing]

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Drug Delivery Systems

Background:

• Thrombin receptor agonist peptide (TRAP-6) shows promise for stimulating damaged tissue regeneration.
• Thrombin's limitations (cost, instability, inflammation) necessitate alternatives like TRAP-6.
• Protecting TRAP-6 from wound peptidases and controlling its release are critical for efficacy.

Purpose of the Study:

• To develop a poly(D,L)-lactide-co-glycolide (PLGA) microparticle system for controlled release of TRAP-6.
• To investigate the impact of TRAP-6 immobilization on PLGA microparticle characteristics and peptide release.
• To assess the stability and degradation of TRAP-6 loaded PLGA microparticles in vitro.

Main Methods:

• PLGA microparticles with immobilized TRAP-6 were fabricated using a double emulsion/evaporation technique.
• Scanning electron microscopy (SEM) was employed to analyze microparticle morphology and porosity.
• TRAP-6 release kinetics were quantified using HEPES buffer (pH 7.5) over 20 hours.
• Microparticle degradation and aggregation were monitored via SEM during incubation.

Main Results:

• Peptide immobilization increased microparticle porosity.
• TRAP-6 exhibited a burst release in the first 2 hours, with complete release within 20 hours.
• Microparticle size and surface porosity increased after 1 day of incubation.
• Microparticle aggregation was observed by day 7, indicating degradation.

Conclusions:

• Immobilization of TRAP-6 into PLGA microparticles provides a viable method for controlled peptide delivery.
• The PLGA matrix protects TRAP-6 from degradation, enhancing its stability.
• This system represents a novel drug delivery approach for applications in tissue regeneration.