IRDye® Infrared Dyes'
Features & Benefits
Figure 1. Animal tissue absorbs visible light. Hemoglobin (Hb) and other tissue components strongly absorb visible light. In the NIR region, where infrared agents are detected, tissue absorbance is dramatically reduced. Above 820 nm, light absorbance by water begins to increase.
IRDye near-infrared dyes are optimized for excitation and detection in the near-infrared spectrum, providing numerous benefits.
- Low background autofluorescence allows higher signal to noise ratios (see Fig. 1)
- Wide range of dyes and functional groups available for multiple applications
- Available in custom derivations of fluorescent dyes and alternative pack sizes through Custom Labeling and Synthesis Services
- Excellent photostability (see Fig. 2)
- Dye brightness (see Fig. 3)
Figure 2. Equimolar amounts of each dye (25 fmol) were spotted onto nitrocellulose membrane. The membrane was scanned repeatedly with the Odyssey® Infrared Imaging System, and signal intensity was normalized to maximum intensity at time = 0
Figure 3. Goat anti-Rabbit IgG conjugates were analyzed at 10µg/mL in physiological buffer. Fluorescence was measured with a PTI fluorometer at optimum ex/em wavelengths for each dye.
Example 1. Low Autofluorescence Enhances Tumor-to-Background Ratio
When autofluorescent background is low:
- Tumors are more easily detected
- Tumor-to-background ratio is increased
- IRDye® 800CW and IRDye 680RD optical probes provide excellent performance for in vivo imaging.
Figure 4. Comparison of IRDye 800CW and Cy® 5.5 EGF probes.1 Mice with MDA-MB-468 tumors were injected with 1 nmol of IRDye 800CW EGF or Cy 5.5 EGF optical probe. Animals were imaged 24 h after injection. A) IRDye 800CW EGF probe - tumor is easily visualized (red circle); B) Cy 5.5 - EGF probe - tumor is difficult to detect. The IRDye 800CW EGF imaging probe yielded a 5.8-fold improvement in tumor-to-background ratio, compared to Cy 5.51.
1. Adams et al. J Biomedical Optics, 12(2), 024017 (2007)