title: Responsive microgrooves for the formation of harvestable tissue constructs.
abstract: Given its biocompatibility, elasticity, and gas permeability, poly(dimethylsiloxane) (PDMS) is widely used to fabricate microgrooves and microfluidic devices for three-dimensional (3D) cell culture studies. However, conformal coating of complex PDMS devices prepared by standard microfabrication techniques with desired chemical functionality is challenging. This study describes the conformal coating of PDMS microgrooves with poly(N-isopropylacrylamide) (PNIPAAm) by using initiated chemical vapor deposition (iCVD). These microgrooves guided the formation of tissue constructs from NIH-3T3 fibroblasts that could be retrieved by the temperature-dependent swelling property and hydrophilicity change of the PNIPAAm. The thickness of swollen PNIPAAm films at 24 °C was approximately 3 times greater than at 37 °C. Furthermore, PNIPAAm-coated microgroove surfaces exhibit increased hydrophilicity at 24 °C (contact angle θ = 30° ± 2) compared to 37 °C (θ = 50° ± 1). Thus PNIPAAm film on the microgrooves exhibits responsive swelling with higher hydrophilicity at room temperature, which could be used to retrieve tissue constructs. The resulting tissue constructs were the same size as the grooves and could be used as modules in tissue fabrication. Given its ability to form and retrieve cell aggregates and its integration with standard microfabrication, PNIPAAm-coated PDMS templates may become useful for 3D cell culture applications in tissue engineering and drug discovery.
authors: Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
authors: Halil
authors: H
authors: Tekin
authors: Gozde
authors: G
authors: Ozaydin-Ince
authors: Tonia
authors: T
authors: Tsinman
authors: Karen K
authors: KK
authors: Gleason
authors: Robert
authors: R
authors: Langer
authors: Ali
authors: A
authors: Khademhosseini
authors: Melik C
authors: MC
authors: Demirel
mesh_terms: D000178:Acrylamides / Q000737:chemistry; D000180:Acrylic Resins; D000327:Adsorption; D000818:Animals; D002417:Cattle; D002448:Cell Adhesion / Q000187:drug effects; D004129:Dimethylpolysiloxanes / Q000737:chemistry* / Q000494:pharmacology; D057927:Hydrophobic and Hydrophilic Interactions; D051379:Mice; D046210:Microfluidic Analytical Techniques; D055616:Microtechnology / Q000379:methods*; D041681:NIH 3T3 Cells; D011108:Polymers / Q000737:chemistry; D012710:Serum Albumin, Bovine / Q000737:chemistry; D013696:Temperature; D023822:Tissue Engineering; D054457:Tissue Scaffolds / Q000737:chemistry*; D020858:Tissue and Organ Harvesting; D014835:Volatilization
chemical_list: D000178:Acrylamides; D000180:Acrylic Resins; D004129:Dimethylpolysiloxanes; D011108:Polymers; C052970:poly-N-isopropylacrylamide; D012710:Serum Albumin, Bovine; C013830:baysilon