A faster and cheaper way to diagnose diseases with high accuracy may be possible with a novel microfluidic chip that could effectively detect minute amounts of biomolecules without the need for complex lab equipment, research at the National University of Singapore finds.
Diseases 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 in recent times. 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.
His team, comprising Dr Kerwin Kwek Zeming and two NUS PhD students Mr Thoriq Salafi and Ms Swati Shikha, published their findings in scientific journal Nature Communications.
Novel approach for disease diagnosis
This novel fluorescent label-free approach uses the lateral shifts in the position of the microbead substrate in pillar arrays, for quantifying the biomolecules, based on the change in surface forces and size, without the need of any external equipment. Due to the usage of lateral displacement, the nano-biomolecules can be detected in real-time and the detection is significantly faster in comparison to fluorescent label based detection.
"These techniques can also be extended to many other types of nano-biomolecules, including nucleic acid and virus detection. To complement this chip technology, we are also developing a portable smartphone-based accessory and microfluidic pump to make the whole detection platform portable for outside laboratory disease diagnostics. We hope to further develop this technology for commercialization," said Prof Zhang.