title: Biofriendly bonding processes for nanoporous implantable SU-8 microcapsules for encapsulated cell therapy.
abstract: Mechanically robust, cell encapsulating microdevices fabricated using photolithographic methods can lead to more efficient immunoisolation in comparison to cell encapsulating hydrogels. There is a need to develop adhesive bonding methods which can seal such microdevices under physiologically friendly conditions. We report the bonding of SU-8 based substrates through (i) magnetic self assembly, (ii) using medical grade photocured adhesive and (iii) moisture and photochemical cured polymerization. Magnetic self-assembly, carried out in biofriendly aqueous buffers, provides weak bonding not suitable for long term applications. Moisture cured bonding of covalently modified SU-8 substrates, based on silanol condensation, resulted in weak and inconsistent bonding. Photocured bonding using a medical grade adhesive and of acrylate modified substrates provided stable bonding. Of the methods evaluated, photocured adhesion provided the strongest and most stable adhesion.
authors.affiliation: Department of Radiology, Dartmouth Medical School, Hanover, NH, USA.
authors.forename: Krishnamurthy
authors.initials: K
authors.lastname: Nemani
authors.forename: Joonbum
authors.initials: J
authors.lastname: Kwon
authors.forename: Krutarth
authors.initials: K
authors.lastname: Trivedi
authors.forename: Walter
authors.initials: W
authors.lastname: Hu
authors.forename: Jeong-Bong
authors.initials: JB
authors.lastname: Lee
authors.forename: Barjor
authors.initials: B
authors.lastname: Gimi
mesh_terms: D000269:Adhesives / Q000737:chemistry; D000818:Animals; D002214:Capsules / Q000737:chemistry*; D002470:Cell Survival; D064987:Cell- and Tissue-Based Therapy; D018914:Cells, Immobilized / Q000166:cytology; D004339:Drug Compounding / Q000379:methods*; D004852:Epoxy Compounds / Q000737:chemistry; D006801:Humans; D007515:Islets of Langerhans / Q000166:cytology*; D059346:Magnets / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry*; D058105:Polymerization; D016062:Porosity; D012821:Silanes / Q000737:chemistry
chemical_list: D000269:Adhesives; D002214:Capsules; D004852:Epoxy Compounds; D012821:Silanes