We demonstrated the adaptive control of two-photon-excited fluorescence from GFP using shaped femtosecond laser pulses. It was possible to achieve a 100% increase in the fluorescence/SH signal ratio, that is, we improved the fluorescence per pump intensity by this method. In our experiment, the use of phase-optimized shaped pulses reduced the photobleaching of a GFP variant by a factor of 4. This simple technique will be useful in overcoming severe difficulties, such as weak fluorescence signals and dye photobleaching caused by excitation pulses with high intensities. We demonstrated similar effects for other GFP variants. This method has a strong potential for immediate application to various important biological and medical studies.
展开▼
