Smith group mixes it up

Posted on 22 August 2017

New research from the Smith group has reported innovative new materials that successfully ‘mix up’ four different components, each of which performs a different job in the final gel.

Transmission electron microscopy (TEM) of a multicomponent gel shows narrow polymer gel fibres that make the material robust (white arrows) and wider self-assembled gel fibres that make the material responsive (black arrows)

Making materials that do multiple different things can be a challenging task yet has the potential to unlock exciting new biological applications. In this recent research paper Vânia Vieira, PhD student, Laura Hay, MChem project student and Professor David Smith, employ a multi-component approach, gaining an understanding of how different active ingredients can be simply mixed together yet still retain their individual activities.

The first component is a soft self-assembling gel, which is highly responsive to pH. This weak gel is physically reinforced by mixing in a robust polymer gel, agarose. Heparin, a key biomolecule that plays key roles in controlling both cell growth and blood coagulation can then be incorporated, with the two different gel networks each playing different roles in controlling the release of heparin from the overall material. Finally, a self-assembling heparin binder can also be mixed into the materials – this binds strongly to the heparin within the gel and completely prevents its release until the whole material has been broken down.

Materials such as these have potential biological applications where controlled release of heparin is desirable. Ultimately, this could lead to systems for slow sustained release of heparin, useful in a hospital setting, where a daily injection of heparin is often required to prevent blood clotting. Alternatively, these materials could be useful as scaffolds for growing cells, where controlled heparin release can help direct tissue growth. Research towards these important applications is currently ongoing in the Smith labs.

Professor Smith said: "Understanding complex self-assembled materials, which contain mixtures of nanoscale systems, is a difficult job. This paper is an important step forwards with multiple functions being programmed into a single material in a simple and rational way."

The researchers are a part of the Molecular Materials research grouping in the Department of Chemistry.

Notes to editors: