Development of a Nanoparticle-based Aptasensor Platform

Omar2Aptamers are synthetic oligonucleotides that can bind target molecules with the selectivity and sensitivity of antibodies, but with numerous advantages.

Aptamers are selected in vitro from a random pool of nucleotides by an evolutionary process that optimizes binding to a given target analyte with exquisite specificity and selectivity. An aptamer sequence can then be synthesized at scale and readily manipulated in non-immunogenic environments, even in highly toxic media or at high temperatures.

Aptamers are also much smaller than antibodies, which ensures that they have the fidelity to recognise small molecules. These are amongst the reasons that aptamers are revolutionizing chemosensors.

Omar Ahmed Alsager (below), is a PhD candidate, jointly supervised by Dr. Justin Hodgkiss (Victoria University of Wellington), and Dr. Geoff Willmott (Industrial Research Limited).

"The aim of my PhD is to develop a new platform for sensitively detecting small molecules like environmental pollutants using aptamer functionalized nanoparticles in conjunction with Izon’s resistive pulse sensing technology.

If I am successful in using the qNano to transduce signals when target molecules bind to aptamer functionalized nanoparticles, I aim to apply the technique to detect endocrine disrupting compounds (EDCs) in the environment.

EDCs are released in sewer effluents, and interfere with human and animal hormone systems, posing severe health risks when found in the environment.

The techniques currently used to detect EDCs such as Gas or Liquid Chromatography-Mass Spectrometry have detection limits higher than the trigger values of these compounds, therefore sophisticated chemical extraction and purification must proceed analysis. Our nanoparticle based aptasensor platform could provide a much more effective way of measuring extremely low concentrations of EDCs in the environment.

Photo: Omar Ahmed Alsager, PhD candidate, jointly supervised by Dr. Justin Hodgkiss (Victoria University of Wellington), and Dr. Geoff Willmott (Industrial Research Limited).