A newly designed hand-held device allows measuring a cancer biomarker using human plasma samples. This new device enables home-based cancer monitoring and improves access to diagnostic testing. The device works much like the monitors that diabetics use to test their blood-sugar levels and could be used in a medical clinic or at home, all without lab work, greatly simplifying the process for cancer testing.
An electrochemical bio‐barcode assay allows protein biomarkers to be analyzed in undiluted and unprocessed human plasma samples. The dynamic DNA/protein complexes, composed of antibody‐labelled DNA motifs (TB and B*C) and redox‐labelled DNA (CR*), eliminate the need for multistep processing and allow sample‐in‐answer‐out analysis. The system integrates biorecognition with signal transduction using molecular (DNA/protein) machines and signal readout using nanostructured electrodes.
A user would mix a droplet of blood in a vial of reactive liquid, then place the mixture onto a strip and insert it into a reader. In minutes, the device would measure an antigen that indicates the degree to which cancer is present. The prototype has been designed to monitor prostate specific antigen (PSA) (log‐linear range of 1 ng mL−1–200 ng mL−1 and a LOD of 0.4 ng mL−1), but according to the researchers, the technology can be easily adapted to measure other markers.
Traynor SM, Wang GA, Pandey R et al. Dynamic Bio-Barcode Assay Enables Electrochemical Detection of a Cancer Biomarker in Undiluted Human Plasma: A Sample-In-Answer-Out Approach. Angew Chem Int Ed Engl. 2020 Oct 7. doi: 10.1002/anie.202009664.