Accurately quantifying total protein concentration is a key to most experiments and is often necessary for isolation, separation, and analysis of proteins by biochemical methods. When it is necessary to determine the total protein concentration in a sample, one of the first factors to consider is the selection of a protein assay method. These choices are typically based upon the compatibility of the method with the samples to be assayed. Each method has its own advantages and disadvantages.
VWR®, Bradford protein assay, proteomics grade
Supplier: VWR Chemicals
The Bradford protein assay is the preferred colorimetric assay for quantifying total protein concentration. Based upon complex formation between basic and aromatic amino acid residues with Coomassie® Brilliant Blue G-250 dye, the Bradford method is easier, faster, and more sensitive than the Lowry method.
Expand 1 Items
VWR® Protein Precipitation Kit
Supplier: VWR Chemicals
The Protein Precipitation Kit utilises a simple trichloroacetic acid (TCA) based method to precipitate proteins in complex mixtures. Only protein in the sample is pelleted, while interfering salts and surfactants remain in the supernatant. A gentle acetone wash removes TCA and co-precipitants allowing the end-user to recover the protein in a small volume of buffer.
Expand 1 Items
Protein quantitation assay kits, Non-Interfering™ (NI™) Protein Assay
Supplier: G-Biosciences
A highly sensitive colorimetric protein assay that overcomes interference of common laboratory agents present in protein solutions and shows minimal protein-to-protein variation. The assay is unaffected by the presence of common laboratory agents such as reducing agents, chelating agents, detergents, amines, sugars, chaotropes, salts, drugs, antibiotics, cobalt, and others.
Expand 1 Items
Histone, from calf thymus, MP Biomedicals
Supplier: MP Biomedicals
Histones are soluble in water (10 mg/ml) or 0,5 N HCl (10 mg/ml), yielding a clear to hazy solution depending on the fraction. They are soluble in 6 M urea (4 to 10 mg/ml), but this will denature the histones.