Two-Photon Fluorescence in Red and Violet Conjugated Polymer Microspheres

Photosensitizer-doped conjugated polymer nanoparticles for simultaneous two-photon imaging and two-photon photodynamic therapy in living cells.

Photosensitizer doped conjugated polymer nanoparticles have been prepared by incorporating polyoxyethylene nonylphenylether (CO-520) into the nanoparticles using a re-precipitation method. The conjugated polymer, poly[9,9-dibromohexylfluorene-2,7-ylenethylene-alt-1,4-(2,5-dimethoxy)phenylene] (PFEMO), was used as the host matrix to disperse tetraphenylporphyrin (TPP) and an energy donor to enha...

A cyanine based fluorophore emitting both single photon near-infrared fluorescence and two-photon deep red fluorescence in aqueous solution.

Optical imaging provides an indispensable way to locate tumors in their early stages with high sensitivity and signal to background ratio. A heptamethine cyanine based fluorophore that emits both single photon near-infrared fluorescence and two-photon deep red fluorescence under physiological conditions was developed. Linear and nonlinear photophysical properties of this fluorophore were invest...

Phase-Conjugated Two-Photon Imaging

It is shown that the use of phase conjugation in one arm of a correlated two-photon imaging apparatus allows undistorted ghost imaging through a region with randomly-varying phase shifts. The images are formed from correlated pairs of photons in such a way that turbulenceinduced phase shifts gained by the photons during passage through the medium cancel pairwise. © 2011 Optical Society of Ameri...

Two-photon Fluorescence Endomicroscopy

Two-photon fluorescence correlation spectroscopy with high count rates and low background using dielectric microspheres

Two-photon excitation fluorescence is a powerful technique commonly used for biological imaging. However, the low absorption cross section of this non-linear process is a critical issue for performing biomolecular spectroscopy at the single molecule level. Enhancing the two-photon fluorescence signal would greatly improve the effectiveness of this technique, yet current methods struggle with me...