Single-cell detection using a thin film transistor photosensor with micro-partitions

A thin film transistor (TFT) photosensor was applied to single-cell detection by identifying cell surface molecules based on chemiluminescence. Micro-partitions were directly fabricated on the TFT photosensor surface by photolithography. The surface of each pixel was surrounded by 25 μm-height partitions, forming areas of approximately 30 μm × 30 μm for cell entrapment and photosensing. Visualization of individual JM cells, stained with mouse anti-human CD8 IgG1 primary antibody and Horseradish peroxidase (HRP)-labeled anti-mouse IgG1 secondary antibody, as bright-pixels was successfully achieved using the micro-partitioned TFT photosensor integrated into a microfluidic chamber. Furthermore, real-time monitoring of HRP-labeled JM cells was also accomplished. The fabrication of micro-partitions on the surface of the TFT photosensor allows highly efficient single-cell entrapment and chemiluminescence-based detection of JM cells. This is the first report of single-cell entrapment and subsequent signal detection on the photosensing area of individual pixels of TFT photosensor. This system will allow high-throughput and real-time analysis of more than 10⁴ cells with minimum optical system requirements.