Multi-photon exited near-infrared II fluorescence lifetime micro-imaging system

Abstract

The invention discloses a multi-photon exited near-infrared II fluorescence lifetime micro-imaging system. In the invention, a 1220 nm femtosecond laser is introduced into an Olympus upright scanningmicroscope, and focused on a sample through a near-infrared anti-reflection objective lens; a near-infrared II fluorescence signal is collected by a large-diameter fiber collimator and coupled into anear-infrared anti-reflection large-diameter optical fiber, and finally detected and converted into an electrical signal by a photomultiplier tube responded by near-infrared II; the electrical signalis amplified and converted into an electrical counting signal by a signal amplifier and input to a TCSPC (time-correlated single photon counting) board, and at the same time the TCSPC counting board receives a synchronous pulse signal, as a timing stopping signal, from a laser for calculate time information of received photons; and after processing by a computer, a near-infrared II two-photon fluorescence lifetime image and a near-infrared II two-photon fluorescence intensity image are achieved. The invention is simple, practical, stable and flexible.

Description

technical field [0001] The invention belongs to the field of microscopic imaging of applied optics, and relates to a near-infrared two-zone fluorescence lifetime microscopic imaging system excited by multiphotons. Background technique [0002] 1. Fluorescence microscopy imaging in the second near-infrared region excited by multiphoton [0003] According to the relevant theory of the biological tissue window, fluorescence in the second near-infrared region (1000-1700nm) has a strong penetrating ability in biological tissue, which is conducive to the realization of large-depth imaging, and biological tissue does not have autofluorescence in this band, so The image has a high signal-to-noise ratio. At present, there are commercial near-infrared second-region fluorescence macroscopic imaging systems on the market, which can realize near-infrared second-region fluorescence macroscopic (whole body) imaging of biological specimens (such as mice). However, this imaging method has ...

AI Technical Summary

Problems solved by technology

[0010] However, there are few commercially available TCSPC microscopic imaging systems based on near-infrared second-zone imaging.

In April 2013, Becker & Hickl GmbH launched a near-infrared (900-1700nm) TCSPC system based on indium gallium arsenide (InGaAs) single-photon avalanche diodes. , expensive, and this kind of "black box" method of use is too simple for scientific researchers, lacks the flexibility of use, and is not conducive to modification and use according to specific experimental conditions

More importantly, this system has not yet been combined with a scanning microscope to realize the fluorescence lifetime microscopy imaging function of the near-infrared second region excited by multiphotons

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