RED 660™ Protein Assay is a single reagent colorimetric assay that outperforms commercial colorimetric assays, including Bradford and improved Coomassie/ Bradford assays. RED 660™ Protein Assay offers greater linearity, greater color stability, and greater compatibility with detergents, reducing agents and other interfering agents compared to the Coomassie assays. The single, ready-to-use reagent allows for rapid analysis of total protein concentration and generates highly reproducible results.
This assay is suitable for the simple and rapid estimation of protein concentration and detects proteins in the range of 50-2000µg/ml. This assay is based on a single proprietary dye-metal complex reagent. The binding of protein to the dye-metal complex under acidic conditions results in a change of color from reddish-brown to green and this change in color density is proportional to protein concentration. The color change is a result of deprotonation of the dye-metal complex at low pH, which is facilitated by interactions with positively charged amino acid groups. Protein estimation can be performed using as little as 0.5µg protein. The protein-dye complexes reach a stable end point in 5 minutes, remaining stable for several days.
The RED 660™ Protein Assay has sufficient reagents for 500 standard test tube assays or 2,500 standard microwell assays.
RED 660™ Protein Assay is compatible with most detergents and its compatibility can be furthered enhanced with Neutralizer™
(See figure 1 below).
INTERFERENCE TO PROTEIN ASSAY
The following table lists the agents compatible with the RED 660 Protein Assay. The table also shows the acceptable concentration of reagents for standard protocols. In most cases, using a correct blank will eliminate or minimize the error caused by interference. * Indicates acceptable concentration when RED 660 Protein Assay Reagent is supplemented with Neutralizer™