Aptamer–gold nanoparticle conjugates for the colorimetric detection of arboviruses and vector mosquito species

The real-time, colorimetric detection of analytes <i>via</i> aptamer-gold nanoparticle technology has proven to be an important, emerging technique within the medical field. Of global health importance, the ability to detect vector mosquito species, such as the <i>Aedes</i> (<i>Ae.</i>) <i>aegypti</i> mosquito, and transmitted arboviruses, such as Zika virus, is paramount to mosquito control and surveillance efforts. Herein, we describe the detection of <i>Ae. aegypti</i> salivary protein for vector identification and the detection of Zika virus to assess mosquito infection status by aptamer-gold nanoparticle conjugates. Key to optimization of these diagnostics were gold nanoparticle capping agents and aptamer degree of labelling (<i>i.e.</i>, the amount of aptamers per gold nanoparticle). In the present study, detection was achieved for as little as 10 ng <i>Ae. aegypti</i> salivary protein and 1.0 × 10⁵ PFU live Zika virus. These aptamer-gold nanoparticle conjugate diagnostics could one day prove to be useful as deployable nano-based biosensors that provide easy-to-read optical read outs through a straightforward red-to-blue colour change either within a diagnostic solution or atop a card/membrane-based biosensor.