Polyacrylamide-based hydrogel coatings improve biocompatibility of implanted pump devices

Area of Science:

• Biomaterials Science
• Medical Device Engineering
• Immunology

Background:

• Subcutaneous implants face fouling and foreign body responses (FBRs), limiting device lifespan.
• Polymer coatings can enhance implant biocompatibility and in vivo performance.
• Existing gold standards like poly(ethylene glycol) have limitations.

Purpose of the Study:

• To develop novel polyacrylamide-based copolymer hydrogels as coatings for subcutaneous implants.
• To reduce FBR and local tissue inflammation compared to gold standard materials.
• To evaluate the biocompatibility and efficacy of these coatings in vivo.

Main Methods:

• Prepared a library of polyacrylamide-based copolymer hydrogels.
• Implanted hydrogel-coated devices into mice for 1-month biocompatibility assessment.
• Coated polydimethylsiloxane disks and silicon catheters with the leading hydrogel.
• Tested HEAm-co-MPAm coated insulin infusion catheters in a rat diabetes model.

Main Results:

• A 50:50 N-(2-hydroxyethyl)acrylamide (HEAm) and N-(3-methoxypropyl)acrylamide (MPAm) copolymer showed superior biocompatibility and reduced inflammation versus gold standards.
• Thin (45 ± 1 μm) HEAm-co-MPAm coatings significantly improved implant biocompatibility.
• HEAm-co-MPAm coated insulin infusion catheters extended functional lifetime in diabetic rats.

Conclusions:

• Polyacrylamide-based copolymer hydrogel coatings offer a promising strategy to enhance implant biocompatibility.
• These novel coatings can significantly reduce FBR and inflammation, prolonging device function.
• This technology has the potential to improve management for patients using implanted devices.