NUS scientists develop novel microfluidic chip for fast, accurate and low-cost disease detection
A team of researchers from the National University of Singapore (NUS) developed an innovative microfluidic chip that promise for a faster and 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.
The low-cost microfluidic chip can quickly and accurately detect and quantify nano-bioparticles using only a standard laboratory microscope without any fluorescent labels.
“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, weighing only 500 mg and is 6mm³ in size. Detection can be performed using standard laboratory microscopes, making this approach highly attractive for use in point-of-care diagnostics,” explained Prof Zhang.
Disease diagnosis requires identification and quantification of various bioparticles such as DNA, RNA, proteins, virus, exosomes, and bacteria. Typically, detection of biomolecules using colorimetric assays or fluorescent labelling increase detection cost and complexity as they rely on expensive optical systems and involvement of multiple sample processing steps requiring minimum sample volumes.
One alternative to reduce cost in disease diagnosis is the adoption of fluorescent label-free bioparticle detection techniques. 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.
The innovation by the NUS team adopts the novel fluorescent label-free approach that 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,” said Prof Zhang.
To complement this chip technology, Prof Zhang said his team is also developing a portable smartphone-based accessory and microfluidic pump to make the whole detection platform portable for outside laboratory disease diagnostics, in the hope of further developing this technology for commercialisation.
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 on 28 March 2018.
This study was supported by a research grant from the Singapore Ministry of Education.