title: Bio-origami hydrogel scaffolds composed of photocrosslinked PEG bilayers.
abstract: We describe the self-folding of photopatterned poly (ethylene glycol) (PEG)-based hydrogel bilayers into curved and anatomically relevant micrometer-scale geometries. The PEG bilayers consist of two different molecular weights (MWs) and are photocrosslinked en masse using conventional photolithography. Self-folding is driven by differential swelling of the two PEG bilayers in aqueous solutions. We characterize the self-folding of PEG bilayers of varying composition and develop a finite element model which predicts radii of curvature that are in good agreement with empirical results. Since we envision the utility of bio-origami in tissue engineering, we photoencapsulate insulin secreting β-TC-6 cells within PEG bilayers and subsequently self-fold them into cylindrical hydrogels of different radii. Calcein AM staining and ELISA measurements are used to monitor cell proliferation and insulin production respectively, and the results indicate cell viability and robust insulin production for over eight weeks in culture.
authors: Department of Chemical and Biomolecular Engineering, Johns Hopkins University, 125 Maryland Hall, Baltimore, Maryland 21218, USA; Institute for NanoBioTechnology, Johns Hopkins University, Baltimore, Maryland 21218, USA.
authors: Mustapha
authors: M
authors: Jamal
authors: Sachin S
authors: SS
authors: Kadam
authors: Rui
authors: R
authors: Xiao
authors: Faraz
authors: F
authors: Jivan
authors: Tzia-Ming
authors: TM
authors: Onn
authors: Rohan
authors: R
authors: Fernandes
authors: Thao D
authors: TD
authors: Nguyen
authors: David H
authors: DH
authors: Gracias
mesh_terms: D000818:Animals; D002460:Cell Line; D005456:Fluorescent Dyes / Q000737:chemistry; D020100:Hydrogels / Q000737:chemistry*; D007328:Insulin / Q000378:metabolism; D050417:Insulin-Secreting Cells / Q000166:cytology / Q000378:metabolism; D051379:Mice; D008856:Microscopy, Fluorescence; D008970:Molecular Weight; D010316:Particle Size; D011092:Polyethylene Glycols / Q000737:chemistry*; D023822:Tissue Engineering; D014466:Ultraviolet Rays
chemical_list: D005456:Fluorescent Dyes; D020100:Hydrogels; D007328:Insulin; D011092:Polyethylene Glycols
keywords: micropatterning; photoencapsulation; regenerative medicine; self-assembly; tissue engineering