Latest paper: optical fibers to replace microscopes for single molecule fluorescence detection
Intensity is not enough. Many techniques in optical microscopy take advantage of analysis methods based on single molecule detection events. These measurements provide access to a wide variety of data such as local concentration, structure or mobility of molecules. However, single molecule detection is a challenging task, which requires complex microscope apparatus and is very difficult to take out of the lab.
A mobile endoscope to observe single molecules.
On collaboration with Bordeaux I University (France), my team has recently demonstrated the possibility to detect single fluorescent molecules with an optical fiber. The original system contains a glass microbead at the end of the optical fiber which works as a tiny lens to focus light. The fiber-microbead ensemble is also used to collect the low amount of light emitted by the individual molecules. That way, the bulky microscope is replaced by a remote fiber sensor connected to a miniaturized USB-connected device. This patented technique opens biomedicine and environment monitoring to single molecule analysis.
Reference
H. Aouani, F. Deiss, J. Wenger, P. Ferrand, N. Sojic, H. Rigneault, "Optical-fiber-microsphere for remote fluorescence correlation spectroscopy", Optics Express 17, 18912-18919 (2009)Free download here