SINGLE MOLECULE BIOSENSORS
FOR REAL-TIME APPLICATIONS
Freely-diffusing confocal microscopy smFRET experiments show that a time resolution of 0.5 milliseconds (left) necessitates the simultaneous recording of approximately 50 molecules (right) to ensure an E signal accuracy of 0.01 standard deviation.
We are developing a comprehensive engineering toolbox for single-molecule biosensors. Our goal is to enable real-time monitoring of complex sub-cellular biological processes within living cells. This innovative approach will have significant implications for various life science applications.
What we have achieved
Monitoring the biosensor for 50 ms gives results. When observing 50 molecules at once, decisions can be made in just 0.5 ms.
A millisecond (ms) is a unit of time equal to one-thousandth of a second (0.001 seconds).
Surface-immobilized TIRF microscopy allows for extended fluorescence recordings, capturing single-molecule images in 50 millisecond snapshots (top). The corresponding E values (bottom) are shown for pH 4 (purple), pH 5 (blue), and pH 6 (green).
Our technology involves designing protein-based sensors that can detect molecular changes with millisecond precision. Unlike typical sensors that act like a simple on/off switch, our sensors function more like a dimmer, providing a continuous signal. This is because they operate on a "conformational rheostat" concept, allowing them to report a range of states instead of just a binary output. This means we can capture more detailed information about the presence and concentration of specific molecules over a broad range of conditions.
