Email bio-eu@licor.com
Dyes for Your Near-Infrared Imaging Needs
Product Ordering Information
Online ordering is available to customers in the US only.
Dye Structure
IRDye® 800CW NHS Ester
The NHS ester reactive group will label primary and secondary amines, such as lysine residues in proteins.
| Solvent | Ext. Coeff. (M-1cm-1) | Abs Max (nm) | Em Max (nm) |
|---|---|---|---|
| Methanol | 300,000 | 778 | 794 |
| Water | 240,000 | 774 | 789 |
| 1X PBS | 240,000 | 774 | 789 |
| PBS: Methanol | 270,000 | 777 | 791 |
NHS ester reacts with a primary aliphatic amine, such as lysine.
Dye label is attached through amide bond.
IRDye Features & Benefits
IRDye near-infrared dyes are optimized for excitation and detection in the near-infrared spectrum,
providing numerous benefits.
Advantages of IRDye® near-infrared dyes:
low background autofluorescence
low light-scattering
higher signal-to-noise ratios
Higher signal-to-noise ratios with near-infrared fluorescence Westerns
True multiplex Western blot detection requires high sensitivity in BOTH fluorescent channels.
Infrared fluorescence: Detect endogenous protein levels in both channels
Visible fluorescence: Insufficient sensitivity in one channel
Western Blot Analysis of ERK Activation
ERK1/2 and phospho-ERK were detected in lysates of unstimulated or EGF-stimulated A431 cells. Two-fold serial dilutions of lysate were loaded. Replicate blots were detected using ERK1/2 or phospho-ERK primary antibodies and secondary antibodies labeled with infrared or visible fluorescent dyes.
[ABOVE] Near-infrared fluorescence (Odyssey Imager): Total ERK (A; 800 nm) and phospho-ERK (B; 700 nm) were clearly detected. In the overlaid image (C), the mobility shift caused by phosphorylation is detected in the EGF-stimulated lysate.
Visible fluorescence (ECL Plex; Typhoon): Total ERK (D; 633 nm) was detected, but phospho-ERK signal (E; 532 nm) was faint and membrane background was high.
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 optical probes provide excellent performance for in vivo imaging.
Comparison of IRDye 800CW and Cy 5.5 EGF probes1
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)
