We have performed two-photon fluorescence detection in a new scheme in which femtosecond laser pulses were delivered thorugh an optical fiber for nonlinear excitation and the emitted fluorescence was collected through the same fiber. Single-mode fibers were determined to give higher detection efficiency than multimode fibers, consistent with theoretical considerations. The utility of fiber-optic sensing based on two-photon fluorescence detection was proved by an experiment that measured the uptake of a targeted drug delivery agent into cultured cancer cells.
© 2002 Optical Society of America
(060.2370) Fiber optics and optical communications : Fiber optics sensors
(170.3890) Medical optics and biotechnology : Medical optics instrumentation
(190.4180) Nonlinear optics : Multiphoton processes
Jing Yong Ye, Mon Thiri Myaing, Theodore B. Norris, Thommey Thomas, and James Baker, Jr., "Biosensing based on two-photon fluorescence measurements through optical fibers," Opt. Lett. 27, 1412-1414 (2002)