Eur. Phys. J. E (2009) 28: 79-87
https://doi.org/10.1140/epje/i2008-10416-2

Regular Article

Bio-inspired network optimization in soft materials — Insights from the plant cell wall

¹ IFS, Massey University, Palmerston North, New Zealand
² MacDiarmid Institute for Advanced Materials and Nanotechnology, MacDiarmid, New Zealand
³ Fonterra, Palmerston North, New Zealand

^* e-mail: m.williams@massey.ac.nz

Received: 17 April 2008
Revised: 14 November 2008
Accepted: 3 December 2008
Published online: 13 January 2009

Abstract

The dynamic-mechanical responses of ionotropic gels made from the biopolymer pectin have recently been investigated by microrheological experiments and found to exhibit behaviour indicative of semi-flexible polymer networks. In this work we investigate the gelling behaviour of pectin systems in which an enzyme (pectinmethylesterase, PME) is used to liberate ion-binding sites on initially inert polymers, while in the presence of ions. This is in contrast to the previous work, where it was the release of ions (rather than ion-binding groups) that was controlled and the polymers had pre-existing cross-linkable moieties. In stark contrast to the semi-flexible network paradigm of biological gels and the previous work on pectin, the gels studied herein exhibit the properties of chemically cross-linked networks of flexible polymers.