Optical traps induce fluorophore photobleaching by two-photon excitation.

ABSTRACT: Techniques combining optical tweezers with fluorescence microscopy have become increasingly popular. Unfortunately, the high-power, infrared lasers used to create optical traps can have a deleterious effect on dye stability. Previous studies have shown that dye photobleaching is enhanced by absorption of visible fluorescence excitation plus infrared trap photons, a process that can be significantly reduced by minimizing simultaneous exposure to both light sources. Here, we report another photobleaching pathway that results from direct excitation by the trapping laser alone. Our results show that this trap-induced fluorescence loss is a two-photon absorption process, as demonstrated by a quadratic dependence on the intensity of the trapping laser. We further show that, under conditions typi

SUBMITTER: Lu S 

PROVIDER: S-EPMC10698272 | biostudies-literature | 2023 Nov

REPOSITORIES: biostudies-literature