Biuret Reagent
Biuret
Biuret reagent
Ready-to-use concentrate
Cat. #: 6302-01
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Description
The Biuret assay is a reliable method to determine the concentration of soluble and insoluble proteins by complexation of peptide bonds with copper(II)ions. In principle, the assay is performed in an alkaline environment, provided by 3% NaOH (final concentration) in the protein solution. Thus, also the protein concentration of insoluble proteins can be determined, in contrast to e.g. Bradford type assays, who work in an acidic environment.
The assay is commonly used, when larger sample volumes are present, due to the relatively low sensitivity (~0.1-5mg/ml).
The protein concentration is determined by colorimetric measurement at 540-550nm.
Biuret complexContent
50ml Biuret solution (standardized solution)
This quantity is sufficient to make ~160 assays in half-micro cuvettes (630µl) or >800 assays using micro cuvettes or microtiter plates
Product use
For microplates mix 60µl of the protein solution (0.5mg/ml) with 66µl Biuret solution. When using Half-Microcuvettes mix 300µl of the protein solution (0.5mg/ml) with 330µl Biuret solution. After 20-30min the samples are measured at 540-550nm using Microcuvetts or Elisa reader.
Reference: sample buffer or H2O.
Sensitivity
> 0.1mg/ml
