Comparison on single molecule microscopy imaging
Image example by ORCA-Quest
   

Experimental condition
Sample：AT1R-EYFP  
Exposure time：100 ms             
Optics：TIRF  
Objective lens :  100× NA 1.49
laser：488 nm 1 mW

The benefits of ORCA-Quest

Dr. Jiachao Xu's experiment requires the detector comes with very low noise, so as the fluorescence of single molecules to be easily recognized from a relatively clean background. In his experience, EM-CCD could offer a good signal to noise ratio. He also tried some other types of cameras before, but none could achieve similar performance.

But this time qCMOS shows excellent performance with a readout noise almost as low as EM-CCD’s, even at the fast mode (0.43e r.m.s.). Almost the same quantity of fluorescent single molecules could be seen from the image of qCMOS and EM-CCD.

In addition, qCMOS has a smaller pixel size of 4.6 ㎛, which means it could be used under some modes: 4.6 ㎛ (1×1 binning), 9.2 ㎛ (2×2 binning) and 18.4 ㎛ (4×4 binning) depending on imaging demands. For example, to balance between sensitivity and localization precision, Dr. Xu choosed 9.2 ㎛ (2×2 binning) setting for the best performance.

In summary, qCMOS shows comparable or even better performance compared with EM-CCD on single-molecule fluorescence imaging. Its advantages on sensitivity, speed and resolution could provide more choices for different scientific imaging applications.

About TIRFM and Dr. Jiachao Xu's research

Dr. Jiachao Xu is from Dr. Kangmin He’s laboratory. Their research is highly praised in the field. The research method of real-time live-cell single particle tracking using TIRFM is "exciting, which will promote many peers to carry out similar research".

*The content presented on this page reflects information available at the time of the interview.