IRDye^® 680RD Carboxylate

Assays that use IRDye^® 680RD conjugates (such as small animal imaging and cell binding assays) may require a "dye-only" control for potential effects or retention of the dye.

• Carboxylate (non-reactive) form of IRDye 680RD is an ideal control.
  Note: The carboxylate dye has no reactive group and cannot be used for labeling.

How is IRDye 680RD carboxylate used?

In vitro cell-based assays

As a control for cell-based assays that monitor binding of a dye-labeled agent.

• Validation of optical agents for in vivo administration

• Evaluation of binding specificity

Small animal in vivo imaging

For evaluation of behavior and clearance of the dye itself

• Timing of dye clearance from the animal's body

• Retention of dye in certain organs or sites (e.g., liver or kidneys)

Labeling Reaction Reference

As a standard to determine the amount of unreacted ("free") dye after IRDye 680RD conjugation and purification.

Residual unreacted dye may cause:

• Artificially high values when dye/protein (D/P) ratio is calculated

• Increased background fluorescence in biological assays