Tunable Supramolecular Gel Properties by Varying Thermal History

Sisir Debnath; Sangita Roy; Yousef M Abul-Haija; Pim W J M Frederix; Susana M Ramalhete; Andrew R Hirst; Nadeem Javid; Neil T Hunt; Sharon M Kelly; Jesús Angulo; Yaroslav Z Khimyak; Rein V Ulijn

doi:10.1002/chem.201806281

Tunable Supramolecular Gel Properties by Varying Thermal History

Chemistry. 2019 Jun 12;25(33):7881-7887. doi: 10.1002/chem.201806281. Epub 2019 May 13.

Authors

Sisir Debnath^{1

2}, Sangita Roy¹, Yousef M Abul-Haija^{1

3}, Pim W J M Frederix^{1

4}, Susana M Ramalhete⁵, Andrew R Hirst^{1

6}, Nadeem Javid^{1

7}, Neil T Hunt^{4

6}, Sharon M Kelly⁸, Jesús Angulo⁵, Yaroslav Z Khimyak⁵, Rein V Ulijn^{1

9

10

11}

Affiliations

¹ WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow, G1 1XL, UK.
² Current Address: Department of Chemistry, Serampore College, 9, William Carey Sarani, Serampore, Hooghly, West Bengal, Pin-712201, India.
³ Current Address: WestCHEM, School of Chemistry, University of Glasgow, Glasgow, G12 8QQ, UK.
⁴ SUPA, Department of Physics, University of Strathclyde, 107 Rottenrow East, Glasgow, G4 0NG, UK.
⁵ School of Pharmacy, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK.
⁶ Current Address: Department of Chemistry, University of York, York, YO10 5DD, UK.
⁷ Current Address: School of Chemistry and Biosciences, University of Bradford, Bradford, BD7 1DP, UK.
⁸ Institute of Molecular Cell and Systems Biology, University of Glasgow, Glasgow, G12 8QQ, UK.
⁹ Advanced Science Research Center (ASRC) at the Graduate Center of the City University of New York (CUNY), 85 St Nicholas Terrace, New York, 10031, USA.
¹⁰ Department of Chemistry, Hunter College, City University of New York, 695 Park Avenue, New York, 10065, USA.
¹¹ Ph.D. programs in Biochemistry and Chemistry, The Graduate Center of the City University of New York, New York, 10016, USA.

PMID: 30945773
DOI: 10.1002/chem.201806281

Abstract

The possibility of using differential pre-heating prior to supramolecular gelation to control the balance between hydrogen-bonding and aromatic stacking interactions in supramolecular gels and obtain consequent systematic regulation of structure and properties is demonstrated. Using a model aromatic peptide amphiphile, Fmoc-tyrosyl-leucine (Fmoc-YL) and a combination of fluorescence, infrared, circular dichroism and NMR spectroscopy, it is shown that the balance of these interactions can be adjusted by temporary exposure to elevated temperatures in the range 313-365 K, followed by supramolecular locking in the gel state by cooling to room temperature. Distinct regimes can be identified regarding the balance between H-bonding and aromatic stacking interactions, with a transition point at 333 K. Consequently, gels can be obtained with customizable properties, including supramolecular chirality and gel stiffness. The differential supramolecular structures also result in changes in proteolytic stability, highlighting the possibility of obtaining a range of supramolecular architectures from a single molecular structure by simply controlling the pre-assembly temperature.

Keywords: hydrogels; peptide amphiphiles; self-assembly; supramolecular chemistry; thermal history.

Grants and funding

258775/FP7 Ideas: European Research Council