Authors: E. Chow, B. Raguse, L. Wieczorek, J.S. Cooper, L.J. Hubble, M.S. Webster, K.-H. Müller
Affilation: CSIRO, Australia
Pages: 37 - 40
Keywords: diagnostics, biosensors, gold nanoparticles, metabolomics, biomarkers
Thiol-functionalised gold nanoparticle chemiresistors can respond to low-molecular weight chemicals through changes in electrical resistance. This low-cost sensor technology is currently being developed for multiple applications including water quality, microbial metabolomics, environmental monitoring, and point-of-care disease diagnostics. Previously, chemiresistors could only be used for gas-phase sensing, restricting their potential applicability. In a major breakthrough, we have shown that chemiresistors can also be used directly in liquids with the potential for screening fluids such as ground water, body fluids such as urine, sweat and saliva, to rapidly detect impurities, contamination or diseases such as cancer, pneumonia and malaria. One research avenue being explored using gold nanoparticle chemiresistors is non-invasive disease diagnostics using human biological samples. We have demonstrated that chemiresistor arrays can detect and discriminate tuberculosis biomarkers, with limits of detection for some tuberculosis biomarkers (o-xylene) only one order of magnitude away from clinically relevant levels. These preliminary results demonstrate the potential for gold nanoparticle chemiresistors to be developed into low-cost portable diagnostic devices due to their high sensitivity, tunable selectivity, simple fabrication and low-power requirements.