Professor Pauline Doran
Biotechnology / Bioengineering / Biomaterials/ Cell Culture Technology
Telephone: 9905-1373
Email: pauline.doran@sci.monash.edu.au
The following projects will be available from mid 2009.
Project 1. Production of semiconductor quantum dots using plant cell culture
Heavy metals such as cadmium are highly toxic to cells. Plant cells detoxify Cd by complexing it with sulphur; under certain conditions CdS nanocrystals are formed. Plants also bind Cd with phytochelatin peptides, which can stabilise the CdS nanocrystal and serve as a complexing agent for further biological functionalisation. An important property of CdS nanocrystals of size 2–20 nanometres is that they behave as semiconductor quantum dots due to quantum confinement effects. Semiconductor nanoparticles have unique electronic and optical properties that depend directly on particle size and many applications of quantum dots in medical imaging, diagnostics, therapy and microelectronics are currently being developed. This project involves investigation of plant cell cultures for biological synthesis of CdS quantum dots, including studying the effect of culture conditions and particle recovery methods on nanocrystal yield and quality.
Project 2. Calcium oxalate crystals in plant tissue cultures
Calcium oxalate crystals are present in the tissues and organs of many higher plants and are the most prevalent and widely distributed form of biological mineral deposit. Plant-generated crystals have very specific and controlled morphologies that are different from those of calcium oxalate crystals produced using chemical methods. For example, some plants produce needle-shaped calcium oxalate crystals and this shape is unique to plants. Crystallisation in plant tissues occurs under biochemical and genetic control: different plant species display specific anatomical, morphological and developmental patterns of crystal accumulation. As well as performing important biological functions in plants, oxalate crystals with specific shapes containing transition and heavy metals are also of interest for development of novel biomaterials such as molecular magnets, and for environmental remediation of polluted soils and waterways. In this project, plant tissue cultures such as hairy roots and suspended cells of several plant species will be investigated for calcium oxalate crystal production. The effect on crystal shape and structure of doping the crystals with metal atoms will be examined to determine whether plant-produced or plant-inspired calcium oxalate crystals display useful properties for industrial applications.
