An invention by a team of researchers from the National University of Singapore (NUS) holds promise for a faster, cheaper way to diagnose diseases with high accuracy. Professor Zhang Yong from the Department of Biomedical Engineering at the NUS Faculty of Engineering and his team have developed a tiny microfluidic chip that could effectively detect minute amounts of biomolecules without the need for complex lab equipment.

Disease diagnostics involves detection and quantification of nano-sized bio-particles such as DNA, proteins, viruses, and exosomes (extracellular vesicles). Typically, detection of biomolecules such as proteins are performed using colorimetric assays or fluorescent labeling with a secondary antibody for detection and requires complex optical detection equipment such as fluorescent microscopy or spectrophotometry.

One alternative to reduce cost and complexity of disease detection is the adoption of label-free techniques, which are gaining traction. However, this approach requires precision engineering of nano-features (in a detection chip), complex optical setups, novel nano-probes (such as graphene oxide, carbon nanotubes, and gold nanorods) or additional amplification steps such as aggregation of nanoparticles to achieve sensitive detection of biomarkers.

"Our invention is an example of disruptive diagnostics. This tiny biochip can sensitively detect proteins and nano-sized polymer vesicles with a concentration as low as 10ng/mL (150 pM) and 3.75μg/mL respectively. It also has a very small footprint,” explained Zhang. “Detection can be performed using standard laboratory microscopes, making this approach highly attractive for use in point-of-care diagnostics.”