Designing Supramolecular Heat-Set Hydrogels for 3D
23rd IUPAC Conference on Physical Organic Chemistry (ICPOC23) 3rd – 8th July 2016 • Sydney • Australia
Designing Supramolecular Heat-Set Hydrogels for 3D Cell Culture Jonathan P. Wojciechowski,a,b Celine Heua,b,c, Adam D. Martina,b and Pall Thordarsona,b* a
b
School of Chemistry, UNSW Australia, Sydney, NSW 2052, Australia. ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, UNSW Australia, Sydney, NSW 2052, Australia. c Biomedical Imaging Facility, UNSW Australia, Sydney, NSW, 2052, Australia *[email protected]
Supramolecular hydrogels have excellent potential in biological applications such as: tissue engineering, drug delivery and cell culture.1 This is as a result of their reversible physical properties derived from non-covalent interactions which structure these materials. Their well-defined chemical composition and biodegradabiltity makes them attractive targets over polymeric equivalents.2 An emerging approach is the development of heat-set hydrogels. Similar to matrigel, upon warming the solution to 37 °C, gelation will occur. Certain polymers can mimic this through an entropic effect known as lower critical solution temperature (LCST) and have been applied in 3D cell culture applications.3 There have however been few examples of small molecule heat-set hydrogels4 and to our knowledge none applied to cell culture. Here we report the self-assembly of N-terminal capped peptides containing the peptide sequence Gly-Phe-Phe-Arg-Gly-Asp (GFFRGD). These peptides have the ability to gelate biologically relevant media upon heating at 37 °C (Figure. 1). We show the mechanism of self-assembly through a combination of spectroscopic techniques and show the resulting materials depend upon the choice of capping group at the peptide N-terminus. We can tune the mechanical properties and kinetics of the materials by altering this capping group. Furthermore, the biocompatibility of these hydrogels is assessed on fibroblast cell lines showing tremendous potential as materials for 3D cell culture.
Figure 1. Time-resolved rheology showing solutions of Fmoc-GFFRGD mixed with DMEM, set at 25 °C and 37 °C respectively. A crossover (whereby G’ > G”) is indicative of a solid-like or gel material. Fmoc-GFFRGD forms a self-supporting hydrogel within 1 h at 37 °C however it is still a solution even after 16 h at 25 °C.
References 1. (a) X. Du, J. Zhou, J. Shi and B. Xu. Chem. Rev. 2015, 115, 13165–13307. (b) S. Fleming and R. V Ulijn. Chem. Soc. Rev. 2014, 43, 8150–8177. 2 3
4
M. J. Webber, E. A. Appel, E. W. Meijer and R. Langer. Nat. Mater. 2015, 15, 13–26. M. H. Park, M. K. Joo, B. G. Choi and B. Jeong. Acc. Chem. Res. 2012, 45, 424–433. (b) P. H. J. Kouwer, M. Koepf, V. A. A. Le Sage, M. Jaspers, A. M. van Buul, Z. H. Eksteen-Akeroyd, T. Woltinge, E. Schwartz, H. J. Kitto, R. Hoogenboom, S. J. Picken, R. J. M. Nolte, E. Mendes and A. E. Rowan. Nature 2013, 493, 651–655. V. J. Nebot, J. J. Ojeda-Flores, J. Smets, S. Fernandez-Prieto, B. Escuder and J. F. Miravet. Chem. Eur. J. 2014, 20, 14465–14472.
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Designing Supramolecular Heat-Set Hydrogels for 3D Cell Culture Jonathan P. Wojciechowski,a,b Celine Heua,b,c, Adam D. Martina,b and Pall Thordarsona,b* a
b
School of Chemistry, UNSW Australia, Sydney, NSW 2052, Australia. ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, UNSW Australia, Sydney, NSW 2052, Australia. c Biomedical Imaging Facility, UNSW Australia, Sydney, NSW, 2052, Australia *[email protected]
Supramolecular hydrogels have excellent potential in biological applications such as: tissue engineering, drug delivery and cell culture.1 This is as a result of their reversible physical properties derived from non-covalent interactions which structure these materials. Their well-defined chemical composition and biodegradabiltity makes them attractive targets over polymeric equivalents.2 An emerging approach is the development of heat-set hydrogels. Similar to matrigel, upon warming the solution to 37 °C, gelation will occur. Certain polymers can mimic this through an entropic effect known as lower critical solution temperature (LCST) and have been applied in 3D cell culture applications.3 There have however been few examples of small molecule heat-set hydrogels4 and to our knowledge none applied to cell culture. Here we report the self-assembly of N-terminal capped peptides containing the peptide sequence Gly-Phe-Phe-Arg-Gly-Asp (GFFRGD). These peptides have the ability to gelate biologically relevant media upon heating at 37 °C (Figure. 1). We show the mechanism of self-assembly through a combination of spectroscopic techniques and show the resulting materials depend upon the choice of capping group at the peptide N-terminus. We can tune the mechanical properties and kinetics of the materials by altering this capping group. Furthermore, the biocompatibility of these hydrogels is assessed on fibroblast cell lines showing tremendous potential as materials for 3D cell culture.
Figure 1. Time-resolved rheology showing solutions of Fmoc-GFFRGD mixed with DMEM, set at 25 °C and 37 °C respectively. A crossover (whereby G’ > G”) is indicative of a solid-like or gel material. Fmoc-GFFRGD forms a self-supporting hydrogel within 1 h at 37 °C however it is still a solution even after 16 h at 25 °C.
References 1. (a) X. Du, J. Zhou, J. Shi and B. Xu. Chem. Rev. 2015, 115, 13165–13307. (b) S. Fleming and R. V Ulijn. Chem. Soc. Rev. 2014, 43, 8150–8177. 2 3
4
M. J. Webber, E. A. Appel, E. W. Meijer and R. Langer. Nat. Mater. 2015, 15, 13–26. M. H. Park, M. K. Joo, B. G. Choi and B. Jeong. Acc. Chem. Res. 2012, 45, 424–433. (b) P. H. J. Kouwer, M. Koepf, V. A. A. Le Sage, M. Jaspers, A. M. van Buul, Z. H. Eksteen-Akeroyd, T. Woltinge, E. Schwartz, H. J. Kitto, R. Hoogenboom, S. J. Picken, R. J. M. Nolte, E. Mendes and A. E. Rowan. Nature 2013, 493, 651–655. V. J. Nebot, J. J. Ojeda-Flores, J. Smets, S. Fernandez-Prieto, B. Escuder and J. F. Miravet. Chem. Eur. J. 2014, 20, 14465–14472.
TH35
