Books like Engines of Creation by Eric Drexler and Prey by Michael Crichton, not to mention the children's movie Agent Codie Banks have made the public aware of the idea of functional (and dangerous) 'nanobots'.In fact, society is a very long way off from being able to design such entities, and it is unlikely they will have the remarkable powers attributed to them by the entertainment media in any case. However, there are many less ambitious but useful possibilities for nano-sized constructs. One idea is to use them to selectively targeting diseased cells or disease-causing organisms. In this scheme, the surface of a nanoparticle is coated with biological molecules that cause it to selectively attach to a target cell. Once in place the nanoparticle can be activated in some manner to destroy the target. In our case we are invoking frequency-selective plasmonic heating of gold nanoparticles as a means of delivering a destructive effect.
Although the destruction of tumour cells by this technique is already being explored by several groups around the world, we have identified a different niche for UTS : unlike any other known group, we have selected a live unicellular parasite as the 'target' for our nanoparticle to attack. The resulting interdisciplinary collaboration is called the 'Nanobody project'. The participants in the project include Prof. Michael Cortie, Dr Stella Valenzuela, Dr Nicky Boulter (IBID) and PhD student Ms Dakrong Pissuwan. Novelty aside, the emphasis of 'Nanobody' on targeting live unicellular parasites provides a means for leveraging the considerable expertise and infrastructure offered by UTS' Institute for Biology of Infectious Diseases - which specialises in such parasites. The project combines Cortie's interests in precious metal nano-materials and sub-wavelength plasmonic effects, with Valenzuela's interest in protein science and immunochemistry. Encouraging progress has been made so far, and gold nanospheres and rods made at UTS have been conjugated with various antibodies and shown to attach selectively to target cells. Cells with attached gold have been selectively killed using low intensity laser illumination of the appropriate wavelength to match the plasmon resonance of the gold particles.