Rapid and Selective Biomarker Detection with Conductometric Sensors

Area of Science:

• Materials Science and Engineering
• Biomedical Engineering
• Nanotechnology

Background:

• Biomarker detection is vital for disease diagnosis, but conventional methods are invasive and uncomfortable.
• Non-invasive biosensing offers a promising alternative for patient comfort and safety.
• Metal oxide-based sensors present an opportunity for developing sensitive and rapid diagnostic tools.

Purpose of the Study:

• To develop and present a novel metal oxide (oxygen-deficient zinc oxide, ZnO) based conductometric sensor platform.
• To enable rapid, non-invasive, and on-demand selective detection of biomarkers in human body fluids.
• To demonstrate the platform's capability using cardiac inflammatory biomarkers Interleukin-6 (IL-6) and C-reactive protein (CRP).

Main Methods:

• Fabrication of two-terminal conductometric sensors utilizing oxygen-deficient ZnO.
• Surface functionalization of sensors for on-demand target selection and enhanced selectivity.
• Real-time electrical resistance measurements for monitoring biomarker concentrations in saliva and sweat samples.
• Testing with model antigens IL-6 and CRP, including selectivity tests with mixed biomarker samples.

Main Results:

• The ZnO biosensors achieved rapid detection (<10 min) of biomarkers with high sensitivity.
• Detected concentrations of IL-6 and CRP significantly lower than healthy levels in saliva and sweat.
• Demonstrated high selectivity for IL-6 and CRP even in the presence of other biomarkers.
• The platform showed potential for detecting viruses or DNA, paving the way for point-of-care devices.

Conclusions:

• The developed ZnO-based conductometric sensor platform offers a novel approach for non-invasive, real-time biomarker detection.
• The technology enables on-demand target selection, short incubation times, and high sensitivity and selectivity.
• This platform has significant potential for developing compact, rapid point-of-care medical devices for early disease diagnosis and monitoring.