ROTI®Quant universal, 500 assays (cuvettes), for biochemistry, plastic

Colorimetric test for detecting and quantifying soluble proteins. Universally applicable.

• Equals the well-known BCA assay
• Very easy to handle
• Highly sensitive measurement up to 0.5 µg protein
• Linear measuring range from 0.5 to 200 µg protein
• Can be used in 1-ml-scales and in microtiter plates (can be automated)
• Measurement with standard filters (492 nm wave length) or at 503 nm wave length
• Accelerated reaction and increased sensitivity in mild heat

The special reagent formula effects a high tolerance against interfering factors such as detergents, alcohol and buffer salts, thus making the kit a universal tool for measuring proteins in almost every solution.

Mechanism

The basic mechanism, a PCA enhanced Biuret reaction, is identical with the one used for the well known BCA protein assay. Its result, however, is a bright blue colour which may be measured with standard filters of approx. 500 nm wave length.

ROTI®Quant universal is based on a biuret reaction in combination with a highly specific colorimetric enhancer reaction. The Cu++ ions of reagent 2 are reduced to Cu+ ions in the alkaline reaction media of the test. The colour development of the copper-specific enhancer reaction is directly proportional to the concentration of the protein which is present.

The resulting purple-coloured copper complex exhibits a strong light absorption with a maximum of 503 nm, although the wide maximum of the absorption curve also permits highly sensitive and no-loss measurements at 492 nm. The reaction does not form a true end point measurement: the colour develops slowly at room temperature, this, however, can be accelerated in heat. High sensitivity, therefore, can be achieved even after a short time.