A method using biodegradable polylactides/polyethylene glycol for drug release with reduced initial burst

Area of Science:

• Biomaterials Science
• Drug Delivery Systems
• Polymer Chemistry

Background:

• Biodegradable polylactides (PLA)/polyethylene glycol (PEG) microspheres are used for drug delivery but exhibit significant initial burst release.
• The hydrophilic polyethylene glycol (PEG) segment in PLA/PEG microspheres protrudes to the surface, contributing to rapid drug release.

Purpose of the Study:

• To investigate the efficacy of post-coating biodegradable PLA/PEG microspheres with a gelatin film to mitigate initial drug burst release.
• To determine the relationship between gelatin coating thickness and drug release kinetics.

Main Methods:

• Biodegradable PLA/PEG microspheres were prepared using a water-in-oil emulsion/solvent evaporation technique.
• Microspheres underwent post-coating via dipping into a dilute gelatin solution.
• Drug release profiles were analyzed to assess the impact of gelatin coating on release rates.

Main Results:

• Post-coating with a gelatin film significantly inhibited the initial burst release of drugs from PLA/PEG microspheres.
• Gelatin post-coating reduced the burst release by 98%.
• An increase in gelatin coating thickness led to a decrease in drug release rates.

Conclusions:

• Gelatin post-coating is an effective strategy to control and reduce initial burst release from PLA/PEG microspheres.
• The drug release rate from coated microspheres is inversely proportional to the coating thickness.
• This method offers a tunable approach for optimizing drug delivery from biodegradable microspheres.