A blood-borne biomarker of cancer and other diseases is now rapidly and accurately measured with the aid of nanotechnology. The diagnostic technique developed at Australia’s University of New South Wales zones involves microRNAs (miRNA), which are short RNA molecules that prevent some messenger RNAs from coding for a specific protein. Abnormal miRNA activity can be an indicator of cancerous tumors and cancer metastasis.A computer representation of the gold coated nanoparticles that make up the dispersible electrodes. Source: University of New South Wales

The method uses gold-coated magnetic nanoparticles with DNA to match the miRNA of diagnostic interest. The particles function as dispersible electrodes, capturing miRNA in the blood stream before being retrieved with a magnet. The procedure is less cost- and time-intensive and detects lower limits relative to quantitative polymerase chain reaction technology. The latter technique returns results in 12 hours while the miRNA protocol requires only 30 minutes.

The sensor is the first to be able to detect concentrations of microRNA from 10 aM to 1 nM in unprocessed blood samples collected by a simple finger prick. It was also demonstrated to distinguish small variations in microRNA concentrations in blood samples of mice with growing tumors.

The researchers are now investigating how a previously developed assay that relies on a malaria protein to detect early-stage cancer cells in the blood, can complement the new cancer diagnostic tool.