Bioinspired colourimetric sensors and indicators through photonic structures

Colourimetric sensors can offer simple, low-cost and selective detection solutions to detect chemical changes. In particular, disposable sensors are cheap and easy-to-use devices for single-shot measurements. Due to increasing requests for in situ analysis or resource-limited areas of the world, we need to develop disposable sensors that are environmentally friendly and have high selectivity and precision in their colour response. Inspired by the colour-switching strategies applied by certain beetle species in nature, this PhD project will explore the development of such colourimetric sensors by building photonic substrates and coupling their surface chemistry with selective chemical markers to trigger a colour response (towards detection of pH, ionic interactions and glucose).

The main elements of the project are:

• Materials chemistry - isolation and chemical modification of the colloidal building blocks
• Soft Matter physics-understanding the self-assembly and colour response in these systems
• Advanced characterisation techniques to analyse the morphological changes coupled by the chemical changes during colour detection.

The project will run as an interdisciplinary collaboration with Professor Devi Stuart-Fox’s research group in the School of BioSciences at the University of Melbourne, where 12 months of research work will take place. This will provide an opportunity to study the growth of structurally coloured beetle species that also shows colour changes towards external chemical and mechanical stimuli. Specifically, the Melbourne component will focus on the growth stages of the helicoidal (bouligand) structures in selected scarab beetles (Scarabaeidae) and the mechanism of colour change in leaf beetles (Chrysomelidae).

This project presents an exciting opportunity to advance bio-inspired engineering and material development towards more cost-effective and greener material technologies for advanced applications. The project also aims to push the material properties further to achieve responses to electric and magnetic fields and sense chemical changes in low concentration levels.