Multipoint fluorescence correlation spectroscopy using spatial light modulator.

A multipoint holographic fluorescence correlation spectroscope (MP-hFCS) was successfully developed. The validity of the MP-hFCS was demonstrated using diffusion measurements of fluorescent dye solutions and of fluorescent proteins in single cells. Furthermore, the successful detection of the nuclear transport of a green fluorescent protein-tagged glucocorticoid receptor α indicates the possibility of being able to monitor directional molecular transport using the MP-hFCS. This allows multipoint analysis of the intermolecular interactions and molecular transport in living cells. Finally, the MP-hFCS can achieve multipoint diffusion measurements with high spatial and time resolution while maintaining a high photon detection sensitivity.