Decentralising and Standardising Blood Processing using Label-free Microfluidics by Assoc Prof Hou Han Wei

On 27 Feburary 2025, Associate Professor Hou Han Wei from NTU's School of Mechanical and Aerospace Engineering (MAE) & Lee Kong Chian School of Medicine gave an exciting talk on "Decentralising and Standardising Blood Processing using Label-free Microfluidics," bringing cutting-edge science and practical applications together. Organised by the Institute of Advanced Studies (IAS) together with the Graduate Student's Club of MAE and School of Biological Sciences, this seminar questioned accepted blood processing paradigms and paved the way for a time when quick, easy, and affordable diagnostics will be the standard. 

Prof Hou gave a fascinating overview of microfluidics at the outset, highlighting its high sensitivity, quick reaction time, and low sample needs - qualities that have the potential to completely transform blood-based diagnostics. Despite their effectiveness, traditional centrifugation-based techniques are laborious and beset by transportation delays and haemolysis. Thus, he emphasised the need for developing new alternatives such as label-free microfluidics technologies for blood cell sorting which do not rely on antibodies. He demonstrated how Dean-Flow Fractionation (DFF) and High Resolution Dean-Flow Fractionation (HiDFF), inertial and mechanical/electrical separation methods, can effectively separate circulating tumour cells from healthy cells, separate platelets and WBCs, and even differentiate microbes of different shapes and sizes, potentially paving path for a breakthrough in antimicrobial resistance (AMR) testing.

A particularly trailblazing development was the ExoArc technology, which facilitates the separation of extracellular vesicle (EVs) - key players in biomarker profiling without high-speed centrifugation, preventing unwanted aggregation and EV loss.

The second half of the seminar revealed a paradigm change in cell detection, an electrical-based approach that does not require staining, imaging, or visual help. Prof Hou developed a high throughput electro-mechano-phenotyping device that detects both mechanical and electrical properties of single cells, allowing:
1) Rapid UTI diagnosis using impedance detection of neutrophils in urine.
2) Monitoring iPSC-derived spinal cord progenitor cells.
3) Immunoprofiling of Type 2 Diabetes Mellitus to assess inflammation risk.

Assoc Prof Hou presenting his development of an electro-mechano-typing device, which detects mechanical and electrical impulses from cells.

Prof Hou concluded with a compelling message regarding the essential gap between research and real-world application, dubbed "The Valley of Death." He challenged scientists, engineers, and business leaders to work together across disciplines, comparing their efforts to the "Avengers" assembling for a common cause.

The seminar concluded with an entertaining Q&A session in which students discussed the detection of similar-sized blood cells, microfluidic yield volumes, and prospective applications for Plasmodium falciparum detection. The conversation encouraged the audience and reinvigorated their commitment to linking science and healthcare for a brighter future. This seminar was more than just a discourse; it was a vision for the future.

Written by  Dasgupta Mallar| NTU School of Biological Sciences Graduate Students' Club

"Presentation was detailed and engaging. Topic was well explained."- Teo Jun Kai (MAE, PhD student)

" Sharing of real life application."- Tan Wei Xin (MSE, PhD student)

"Learned about the technology’s working principles, as well as its advantages and disadvantages."- anonymous (ERI@N, Research Staff)