Engineering Biocoatings To Prolong Drug Release from Supraparticles

Area of Science:

• Biomaterials Science
• Nanotechnology
• Drug Delivery Systems

Background:

• Supraparticles (SPs) offer potential for sustained drug release but suffer from initial burst release, limiting therapeutic efficacy and causing toxicity.
• Controlling the release kinetics of therapeutic compounds from SP depots is crucial for biomedical applications.

Purpose of the Study:

• To develop a biocoating strategy for silica-SPs (Si-SPs) to mitigate burst release of loaded therapeutic proteins.
• To investigate the sustained release profiles of lysozyme and neurotrophins from fibrin-coated Si-SPs (^FSi-SPs).
• To evaluate the impact of a hydrogel-based system on drug release kinetics for surgical delivery.

Main Methods:

• Coating Si-SPs with a fibrin film formed via enzymatic conversion of fibrinogen.
• Loading model protein lysozyme and neurotrophins onto ^FSi-SPs.
• Characterizing drug release profiles of coated and uncoated Si-SPs over time.
• Encapsulating ^FSi-SPs within an alginate-based hydrogel scaffold for delivery.

Main Results:

• ^FSi-SPs demonstrated significantly reduced burst release of lysozyme (>60% released over >20 days vs. <3 days for uncoated Si-SPs).
• Fibrin coating also delayed neurotrophin release (10% over 21 days vs. 60% for uncoated Si-SPs).
• Encapsulation in an alginate hydrogel further extended lysozyme release to ~40 days.

Conclusions:

• Fibrin biocoating is an effective strategy to control burst release from Si-SPs, enhancing their utility for sustained drug delivery.
• The combination of SPs with hydrogel systems offers tunable drug release kinetics for advanced biomedical applications.
• This approach expands the versatility of SP drug delivery platforms, enabling high loading capacity and prolonged therapeutic compound release.