Description
Key facts
Detection method:Colorimetric,
Sample types:Food samples, Serum, Other biological fluids,
Assay type:Quantitative,
Assay Platform:Microplate
Product details:
DPPH assay kit ab289847 is used to quantify the antioxidant capacity of samples including foods, beverages, biological fluids (e.g. human serum), etc. The DPPH assay is also referred to as the DPPH antioxidant assay and the DPPH radical scavenging assay.
DPPH assay principle
The DPPH assay is based on the stable free radical 2,2-diphenyl-1-picrylhydrazyl radical (DPPH). In the assay, DPPH, which is deep blue in color, is reduced by reaction with antioxidants to form 2,2-diphenyl-1-picrylhydrazine (DPPH-H), which is pale yellow in color. This color change is measured by a decrease in absorbance at 517 nm, corresponding to the blue color of DPPH. The decrease in absorbance is proportional to the antioxidant capacity of the sample.
The synthetic antioxidant, Trolox is included in this assay kit and is used to standardize the sample antioxidant capacity relative to Trolox (Trolox Equivalents Antioxidant Capacity, TEAC).
The Safety Datasheet for this product has been updated for certain countries. Please check the current version in the Support and downloads section.
Properties and Storage Information:
Shipped at conditions-Blue Ice, Appropriate short-term storage conditions-+4°C, Appropriate long-term storage conditions-+4°C, Storage information-Please refer to protocols
Supplementary Information:
This supplementary information is collated from multiple sources and compiled automatically.
DPPH also known as 11-diphenyl-2-picrylhydrazyl is a stable free radical. It has a molecular mass of 394.32 g/mol. Scientists often use it in its radical form which presents as a deep violet color. This color changes upon reduction making it an excellent marker for antioxidant activity. While DPPH is not a biological protein it is extensively used in vitro to evaluate the free radical scavenging activities of antioxidants.
Biological function summary
In vitro antioxidant assays such as the DPPH assay measure how substances can neutralize free radicals. These assays use the DPPH molecule as a tool to quantify antioxidant activity in different samples. The DPPH assay protocol involves observing the change in color from deep violet to a pale yellow as antioxidants in the sample reduce DPPH radicals to non-radical DPPH-H form. The degree of color change reflects the sample's antioxidant capacity.
Pathways
DPPH assays help in understanding oxidative stress pathways by measuring the antioxidants' ability to counteract free radicals. These assays relate to pathways involving the oxidative stress response such as the Nrf2 signaling pathway which modulates the expression of antioxidant proteins. Although the DPPH radical itself does not participate in biological pathways its use in assays helps track activities alongside key proteins like glutathione.
Oxidative stress plays a significant role in chronic inflammation and cardiovascular diseases. Antioxidant assessments using the DPPH test help evaluate how certain compounds might prevent or mitigate these conditions by neutralizing harmful free radicals. The assay indirectly links to disease mechanisms influenced by proteins like NADPH oxidase which generates oxidative stress associated with these diseases.
