HKU team developed a novel photonic chipscope for label-free monitoring of live cell activities

Dr Yuan Lin, Associate Professor of Department of Mechanical Engineering and Dr Zhiqin Chu, Assistant Professor of Department of Electrical & Electronic Engineering had worked on a research for the topic “A Versatile, Incubator-Compatible, Monolithic GaN Photonic Chipscope for Label-Free Monitoring of Live Cell Activities”. The research has been published by Advanced Science on April 11, 2022.

Details of the publication:

A Versatile, Incubator-Compatible, Monolithic GaN Photonic Chipscope for Label-Free Monitoring of Live Cell Activities

Yong Hou, Jixiang Jing, Yumeng Luo, Feng Xu, Wenyan Xie, Linjie Ma, Xingyu Xia, Qiang Wei, Yuan Lin, Kwai Hei Li, Zhiqin Chu

Article in Advanced Science,


The ability to quantitatively monitor various cellular activities is critical for understanding their biological functions and the therapeutic response of cells to drugs. Unfortunately, existing approaches such as fluorescent staining and impedance-based methods are often hindered by their multiple time-consuming preparation steps, sophisticated labeling procedures, and complicated apparatus. The cost-effective, monolithic gallium nitride (GaN) photonic chip has been demonstrated as an ultrasensitive and ultracompact optical refractometer in a previous work, but it has never been applied to cell studies. Here, for the first time, the so-called GaN chipscope is proposed to quantitatively monitor the progression of different intracellular processes in a label-free manner. Specifically, the GaN-based monolithic chip enables not only a photoelectric readout of cellular/subcellular refractive index changes but also the direct imaging of cellular/subcellular ultrastructural features using a customized differential interference contrast (DIC) microscope. The miniaturized chipscope adopts an ultracompact design, which can be readily mounted with conventional cell culture dishes and placed inside standard cell incubators for real-time observation of cell activities. As a proof-of-concept demonstration, its applications are explored in 1) cell adhesion dynamics monitoring, 2) drug screening, and 3) cell differentiation studies, highlighting its potential in broad fundamental cell biology studies as well as in clinical applications.