Microenvironment-regulated dual-hydrophilic coatings for glaucoma valve surface engineering

Area of Science:

• Biomaterials Science
• Surface Engineering
• Ophthalmology

Background:

• Glaucoma valves (GVs) are crucial for glaucoma treatment but face challenges with post-implantation fibrosis, limiting long-term efficacy.
• Fibrosis and inflammatory responses around implanted GVs can lead to device failure and reduced therapeutic effect.

Purpose of the Study:

• To engineer a microenvironment-regulated, dual-hydrophilic antifouling coating for silicone rubber (SR) glaucoma valves.
• To enhance the biocompatibility and long-term success of GVs by mitigating fibrosis and inflammation.

Main Methods:

• Developed a superhydrophilic polydopamine (SPD) coating on SR, leveraging its antifouling and antioxidant properties.
• Utilized SPD's photocatalytic activity to polymerize poly 2-methylacryloxyethylphosphocholine (pMPC), creating a dual-hydrophilic surface with long-range antifouling effects.
• Evaluated the coating's performance through in vitro tests for anti-protein contamination, anti-oxidation, anti-inflammation, and anti-fiber proliferation, followed by in vivo assessments of fibrosis reduction.

Main Results:

• The dual-hydrophilic coating demonstrated significant resistance to protein adsorption, oxidative stress, and inflammatory cell adhesion in vitro.
• In vitro studies showed a marked reduction in fibroblast proliferation, indicating antifibrotic potential.
• In vivo tests confirmed that the coated SR material substantially inhibited fibrous encapsulation, reducing inflammation and fibrosis around the glaucoma valve implant.

Conclusions:

• The microenvironment-regulated, dual-hydrophilic coating effectively improves the biocompatibility of silicone rubber for glaucoma valves.
• This surface engineering strategy shows promise in preventing fibrosis and inflammation, potentially leading to improved long-term outcomes for glaucoma implants.
• The developed coating provides a valuable model for surface modification of medical devices to enhance biocompatibility and reduce foreign body response.