High-throughput relative DPPH radical scavenging capacity assay

Area of Science:

• Analytical Chemistry
• Biochemistry
• Pharmacology

Background:

• Accurate measurement of antioxidant activity is crucial for natural product research.
• Existing methods for assessing 2,2-diphenyl-1-picryhydrazyl (DPPH) radical scavenging capacity can be time-consuming and lack standardization for comparing diverse antioxidant types.

Purpose of the Study:

• To develop and validate a high-throughput relative 2,2-diphenyl-1-picryhydrazyl (DPPH) radical scavenging capacity (RDSC) assay.
• To enable direct comparison of antioxidant capacities across different laboratories and solvent systems.

Main Methods:

• Development of a high-throughput assay for relative DPPH radical scavenging capacity (RDSC).
• Validation of the assay for accuracy (90-110% recovery), precision (3.9-7.0% pooled RSD), and reproducibility (2.2-3.5% interday/intraday RSD).
• Adaptation of the assay for both aqueous alcohol/acetone (hydrophilic antioxidants) and organic solvents (lipophilic antioxidants) without solubilizing agents.

Main Results:

• The developed high-throughput RDSC assay demonstrates acceptable accuracy, precision, and reproducibility.
• The assay allows for the reporting of RDSC values, facilitating inter-laboratory comparisons.
• The method permits direct comparison of hydrophilic and lipophilic antioxidant radical scavenging capacities.

Conclusions:

• The high-throughput RDSC assay is a reliable and efficient tool for evaluating antioxidant potential.
• This assay can be used for EC50 value estimation and screening of natural antioxidants.
• The method's versatility supports the direct comparison of diverse antioxidant compounds.