Effect of sequence on the mechanical properties of β ...

Effect of sequence on the mechanical properties of β-sheet peptide hydrogels with identical charges Jacek

1 Wychowaniec *,

Andrew

1 Smith , Aline

F.

2 Miller ,

and Alberto

1 Saiani

1School

of Materials and Manchester Institute of Biotechnology, University of Manchester, UK. 2School of CEAS and Manchester Institute of Biotechnology, University of Manchester, UK. *[email protected]

1. Introduction

3. Peptide titration

1mg/ml 10 mg/ml net charge

2. Aim

pKa C−terminus = 2.18

pKa Glutamic acid (E) = 4.25

1mg/ml 10 mg/ml net charge

4. Choice of +2 charge F8

pKa N−terminus = 9.13

pKa Lysine (K) = 10.53

1mg/ml 10 mg/ml net charge SC

 10 10 Z    N i pH   N pKai pKaj j pH 10  10 10  10 j  i pKai

pH

   

2

BE

5. Physical properties a)

35.7 mM b) Concentration + 2 charge

F8 SC BE + 2 charge

F8 SC BE

β-sheet

F8

SC

6. Conclusions

BE

1. 2. 3. Acknowledgements: The authors would like to thank: the EPSRC Fellowship (Grant no: EP/K016210/1), EPSRC DTC NOWNANO funding and EPSRC DTA School of Material Science University of Manchester for providing financial support to this project.

While maintaining the same charge state on 3 different peptides, there is a difference in the physical properties of the hydrogels produced. Self-assembly process depends upon charge distribution in the primary peptide sequence. Stress-recovery experiments yield high difference in re-assembly process of selfassembled fibre hydrogels.

References: 1) Castillo Diaz, L. a., Saiani, a., Gough, J. E., & Miller, a. F. (2014).J. Tissue Eng., 5. 2) Tang, C., Miller, A. F., & Saiani, A. (2014). Int. J. Phytorem., 465(1-2), 427–35. 3) Roberts, D., Rochas, C., Saiani, A., & Miller, A. F. Langmuir. 2012 Nov 20; 28(46):16196-206.