S1 Design and 3D Printing of Hydrogel Scaffolds with Fractal ...
Design and 3D Printing of Hydrogel Scaffolds with Fractal Geometries
John Warner1+, Pranav Soman1+, Wei Zhu1, Mathew Tom1, and Shaochen Chen1* 1
Department of NanoEngineering, University of California, San Diego 9500 Gilman Drive, La Jolla, CA 92093 * Correspondence to: [email protected]
Supporting Information: -SEM of high aspect ratio PEGDA hydrogel with TEMPO [0.1%] -Composite fluorescent microscope image of live/dead stain C2C12’s on hydrogel
Manuscript statement (S1): “Although gradient slopes present little difficultly as seen in our laboratory’s previous work, truly vertical sidewalls are difficult to achieve when using soft polymer compositions of HMBS without increasing TEMPO.”
Image Description (S1): SEM image (Figure S1) of a 20 x 50 micron extension of a branched single height fractal layer. Composition: PEGDA [~100%], Irgacure 2959 [1.0%], TEMPO [0.1%]. Fabrication: P = 1.3 W/cm2 ; t = 8 ±4 sec. Since TEMPO has been shown to be cytotoxic in moderate doses, we intentionally have not used images of hydrogel structures containing higher concentrations of this particular free radical terminator to prevent potential confusion
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and misrepresentation of our data. This high TEMPO composition conflicts with our intent to use these structures in future work towards differentiating MSC’s
Figure S1
Manuscript statement (S2): “The printed hydrogel structure was shown as sufficiently biocompatible to murine fibroblast 10T1/2’s.”
Image Description (S2): Fluorescent microscope image of LIVE/DEAD (ThermoFisher) stain of murine fibroblasts 10T1/2 (ATCC) on fibronectin conjugated PEGDA hydrogel. Day 5 of incubation on scaffolds. Channels: (Green = Live - Calcein AM), (Red = Dead-ethidium homodimer-1), and (Gray = bright field). Image assembled in Image J.
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Substrate Composition (S2) 50% Poly (ethylene glycol) diacrylate PEGDA (Mn = 575), in water solution, 2,2,6,6-tetramethylpiperdine 1-oxyl TEMPO [0.01% w/v], 5-Benzoyl-4-hydroxy-2methoxybenzenesulfonic acid HMBS [0.1% w/v], acrylic acid [1.0% v/v] and Irgacure 2959 [1.0% w/v]. Figure S 2
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John Warner1+, Pranav Soman1+, Wei Zhu1, Mathew Tom1, and Shaochen Chen1* 1
Department of NanoEngineering, University of California, San Diego 9500 Gilman Drive, La Jolla, CA 92093 * Correspondence to: [email protected]
Supporting Information: -SEM of high aspect ratio PEGDA hydrogel with TEMPO [0.1%] -Composite fluorescent microscope image of live/dead stain C2C12’s on hydrogel
Manuscript statement (S1): “Although gradient slopes present little difficultly as seen in our laboratory’s previous work, truly vertical sidewalls are difficult to achieve when using soft polymer compositions of HMBS without increasing TEMPO.”
Image Description (S1): SEM image (Figure S1) of a 20 x 50 micron extension of a branched single height fractal layer. Composition: PEGDA [~100%], Irgacure 2959 [1.0%], TEMPO [0.1%]. Fabrication: P = 1.3 W/cm2 ; t = 8 ±4 sec. Since TEMPO has been shown to be cytotoxic in moderate doses, we intentionally have not used images of hydrogel structures containing higher concentrations of this particular free radical terminator to prevent potential confusion
S1
and misrepresentation of our data. This high TEMPO composition conflicts with our intent to use these structures in future work towards differentiating MSC’s
Figure S1
Manuscript statement (S2): “The printed hydrogel structure was shown as sufficiently biocompatible to murine fibroblast 10T1/2’s.”
Image Description (S2): Fluorescent microscope image of LIVE/DEAD (ThermoFisher) stain of murine fibroblasts 10T1/2 (ATCC) on fibronectin conjugated PEGDA hydrogel. Day 5 of incubation on scaffolds. Channels: (Green = Live - Calcein AM), (Red = Dead-ethidium homodimer-1), and (Gray = bright field). Image assembled in Image J.
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Substrate Composition (S2) 50% Poly (ethylene glycol) diacrylate PEGDA (Mn = 575), in water solution, 2,2,6,6-tetramethylpiperdine 1-oxyl TEMPO [0.01% w/v], 5-Benzoyl-4-hydroxy-2methoxybenzenesulfonic acid HMBS [0.1% w/v], acrylic acid [1.0% v/v] and Irgacure 2959 [1.0% w/v]. Figure S 2
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