Fluorescent optical imaging is an excellent way to examine the biodistribution of cells or labeled targeting agents as they are cleared from and/or specifically retained in the animal.
Biodistribution can be imaged and tracked in the live animal over time, allowing you to watch the clearance and specific retention of your labeled agent.
After in vivo imaging, excised tissues can be imaged ex vivo to confirm and quantify accumulation of the agent in tumors, tissues, and organs.
Tissue sections can be viewed with an imager or microscope for additional information about the localization of the agent.
Near-infrared dyes, such as IRDye® fluorophores, and carefully optimized hardware are critical for high-performance optical imaging.
Near-infrared fluorophores exploit the spectral region where light absorption and scatter properties of tissue are most advantageous1. This enhances penetration depth (access of excitation light to the fluorophore) and escape of emitted fluorescence from the animal to reach the detector.
Laser illumination delivers very intense excitation light of the correct wavelength, generating the brightest possible signal from the fluorescent agent.
Intrinsic autofluorescence from animal tissue can mask the signal from optical probes. In the NIR spectral region, autofluorescence is dramatically lowered 2,3.
The Pearl® Imager permits rapid time-lapse imaging of vasculature and lymphatics.
Note: IRDye® 680LT dye products should not be used for small animal in vivo imaging or In-Cell Western™ Assays. The higher level of fluorescent intensity creates high background making it unfavorable for use in these applications. We recommend using IRDye 680RD dye products for these applications.
1. Tsien, R. Science. Vol. 324, May 8, 2009
2. Hawrysz, DJ and Sevick-Muraca, EM. Neoplasia 2(5): 388-417 (2000)