Portable and Wavelength-Tunable Two-Photon Microscopy
Project Award Date: 09-01-2006
Description
Efforts to achieve a detailed understanding of biological systems at the cellular and molecular levels require advance imaging and microscopy. Compared to standard confocal microscopy, two-photon excitation offers distinct advantages. These include better resolution, less background noise, deeper tissue penetration, and less photo-damage. However, a high peak-power Ti:Sapphire laser has until now been required as the excitation source. High cost and cumbersome size are among the Ti:Sapphire laser’s disadvantages, severely limiting practical applications for two-photon microscopy. During the last decade, rapid advances in fiber-optic communications have made fiber-based optical devices widely available and affordable. A femtosecond fiber laser the size of a small textbook can deliver more than 8kW peak power of optical pulses.
In this project, researchers will demonstrate a wavelength-tunable near-infrared light source, called TP-FLEX, for two-photon microscopy. The system is based on the integration of an ultrafast fiber laser, a soliton-based tunable fiber-optic wavelength shifter, and a fluorescence microscope. In addition to a substantially simpler generation of excitation optical pulses, rapid wavelength tunability provided by TP-FLEX will significantly enhance the capability of two-photon microscopy. Multi-color labeling of biological samples combined with the ability of wavelength-tunable excitation will enable rapid multi-color imaging through time-domain synchronization between the detector and the excitation source. Moreover, the TP-FLEX tunable laser system will be compact and the wavelength shifting fiber will serve to flexibly interconnect between the fiber laser and the microscope, allowing portability of the light source. This system will result in increased accessibility of multi-photon microscopy for a wide range of biological, chemical, and analytical applications.
Investigators
Faculty Investigator(s): Ronqing Hui (PI)
Student Investigator(s): Rajprasad Loganathan, Jennifer Thomas, Elliott Price, Gideon VanRiette, Sarvesh Varatharajan
Project Sponsors
Primary Sponsor(s): National Institutes of Health--NCRR
