Measure Protein Pierce 660; Measure Total Protein Concentration - Thermo Scientific NanoDrop One User Manual

Measure Protein Pierce 660

Measure Total Protein Concentration

Theory of Protein Pierce 660 assay
Thermo Scientific
Measures total protein concentration of
unpurified protein samples using a
proprietary colorimetric detection
reagent.
Measure Total Protein
Reported Results
Settings
Detection Limits
The Protein Pierce 660 assay uses a proprietary protein binding material as a
colorimetric detection reagent to determine total protein concentration in unpurified
protein samples. This application is suitable for protein solutions that contain high
concentrations of detergents, reducing agents and other commonly used reagents.
The Pierce 660 application measures absorbance at 660 nm and uses a standard
curve to calculate protein concentration (see
information). A single-point baseline correction is applied.
The Protein Pierce 660 assay is based on the binding of a proprietary dye-metal
complex to protein in acidic conditions that causes a shift in the dye's absorption
maximum, which is measured at 660 nm. The dye-metal complex is reddish-brown
and changes to green upon protein binding. The color change is produced by
deprotonation of the dye at low pH facilitated by interactions with positively charged
amino acid groups in proteins. The dye interacts mainly with basic residues in
proteins such as histidine, arginine and lysine and to a lesser extent tyrosine,
tryptophan and phenylalanine. The reaction product is measured at 660 nm and
baseline-corrected using the absorbance value at 750 nm.
The color produced in the assay is stable and increases in proportion to a broad
range of increasing protein concentrations. An optional Ionic Detergent Compatibility
Reagent (IDCR) may be added to the assay reagent to increase compatibility with
high amounts of ionic detergents, including Laemmli SDS sample buffer with
bromophenol blue. The IDCR dissolves completely by thorough mixing and has no
effect on the assay. Pre-formulated kits of the protein binding material are available
from us or a local distributor. For information about IDCR, refer to the kit
manufacturer.
5
Protein Applications
Measure Protein Pierce 660
Working with Standard Curves
NanoDrop One User Guide
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