Biomedical Engineering

“On-the-fly” imaging bioassay platform for cost-effective biomedical diagnosis

Optical microscopy is now seamlessly integrated with many bioassay technologies for disease diagnosis. However, current techniques lack the throughput to image large and heterogeneous cell and tissue samples systematically. In addition, the vast majority of the methods overwhelmingly rely on biochemical markers such as stains and antibodies for enhancing image contrast, which are however not always be cost effective and efficient. To address these challenges, this project is to develop a spinning disk bioassay platform, which enables ultralarge-scale, label-free, high-resolution “on-the-fly” single-cell or whole-tissue-slide imaging at an imaging rate of 100-times faster than current assays. This high-throughput and high-content technology could open a new paradigm in data-driven bioassay applied in disease diagnostics, and biotechnology industries.

Advancing optical label-free cellular imaging – from instrumentation to cell assays

Quantitative phase imaging (QPI) is an advanced optical microscopy technique that requires no sample staining and allows quantitative measurement of biophysical parameters of the cell specimens. This technique is desirable especially in live-cell imaging, as it can yield cellular dry mass distribution, intracellular dynamics as well as size of cells with minimal intervention/damage to the sample. A compact and easily-compatible setup of QPI was developed and applied to a wide range of biomedical applications, ranging from fundamental biological studies in brain imaging, to the clinical studies in drug-screening for breast cancer cells and characterization of pathogenic bacteria biofilms.

Single cell traction force measurement assay with multiphoton-based protein micropatterns

A multiphoton-based protein micropatterning technique was developed in our lab previously. In this project, protein micropillar arrays were fabricated for cell seeding, and it was utilized for single cell traction force measurement. On the other hand, a method for encapsulating cells in collagen gel for cell therapy was also developed in the lab before. In order to improve the efficiency of cell therapy using this method, characteristics of these cells has to be identified. Therefore, the traction force of stem cells that are migrated out from the gel and the cells that are not encapsulated in the gel were measured and compared to understand the differences between them.