title: Gas-Foamed Scaffold Gradients for Combinatorial Screening in 3D.
abstract: Current methods for screening cell-material interactions typically utilize a two-dimensional (2D) culture format where cells are cultured on flat surfaces. However, there is a need for combinatorial and high-throughput screening methods to systematically screen cell-biomaterial interactions in three-dimensional (3D) tissue scaffolds for tissue engineering. Previously, we developed a two-syringe pump approach for making 3D scaffold gradients for use in combinatorial screening of salt-leached scaffolds. Herein, we demonstrate that the two-syringe pump approach can also be used to create scaffold gradients using a gas-foaming approach. Macroporous foams prepared by a gas-foaming technique are commonly used for fabrication of tissue engineering scaffolds due to their high interconnectivity and good mechanical properties. Gas-foamed scaffold gradient libraries were fabricated from two biodegradable tyrosine-derived polycarbonates: poly(desaminotyrosyl-tyrosine ethyl ester carbonate) (pDTEc) and poly(desaminotyrosyl-tyrosine octyl ester carbonate) (pDTOc). The composition of the libraries was assessed with Fourier transform infrared spectroscopy (FTIR) and showed that pDTEc/pDTOc gas-foamed scaffold gradients could be repeatably fabricated. Scanning electron microscopy showed that scaffold morphology was similar between the pDTEc-rich ends and the pDTOc-rich ends of the gradient. These results introduce a method for fabricating gas-foamed polymer scaffold gradients that can be used for combinatorial screening of cell-material interactions in 3D.
authors: Polymers Division, National Institute of Standards & Technology, 100 Bureau Drive, Gaithersburg, MD 20899, USA. kchatterjee@materials.iisc.ernet.in.
authors: Kaushik
authors: K
authors: Chatterjee
authors: Polymers Division, National Institute of Standards & Technology, 100 Bureau Drive, Gaithersburg, MD 20899, USA. alison.kraigsley@nist.gov.
authors: Alison M
authors: AM
authors: Kraigsley
authors: New Jersey Center for Biomaterials, Rutgers University, Piscataway, NJ 08854, USA. bolikal@biology.rutgers.edu.
authors: Durgadas
authors: D
authors: Bolikal
authors: New Jersey Center for Biomaterials, Rutgers University, Piscataway, NJ 08854, USA. kohn@rutgers.edu.
authors: Joachim
authors: J
authors: Kohn
authors: Polymers Division, National Institute of Standards & Technology, 100 Bureau Drive, Gaithersburg, MD 20899, USA. carl.simon@nist.gov.
authors: Carl G
authors: CG
authors: Simon