Curcumin Electroanalysis at a Disposable Graphite Electrode.

Area of Science:

• Electrochemistry
• Analytical Chemistry
• Phytochemistry

Background:

• Curcumin (CU), derived from turmeric, possesses significant health benefits and antioxidant properties.
• Increased interest in CU's therapeutic applications necessitates reliable analytical methods for its quantification.
• The guaiacol moieties in CU are key to its antioxidant activity and electrochemical behavior.

Purpose of the Study:

• To develop and validate a voltammetric method for the sensitive quantification of curcumin (CU).
• To investigate the electrochemical behavior of CU at a pencil graphite electrode (PGE).
• To assess the practical applicability of the developed method for CU analysis in dietary supplements.

Main Methods:

• Utilized cyclic and differential pulse voltammetry (DPV) at a single-use pencil graphite electrode (PGE).
• Conducted theoretical calculations to predict CU's geometry and electrochemical potential.
• Optimized conditions using 0.05 mol/L sulfuric acid and determined detection and quantification limits.

Main Results:

• Electrode processes for CU were found to be pH-dependent, involving protons and electrons.
• A linear relationship was observed between DPV cathodic peak intensity and CU concentration (5.00 × 10⁻⁸–5.00 × 10⁻⁶ mol/L).
• The method achieved low detection (2.12 × 10⁻⁸ mol/L) and quantification (6.42 × 10⁻⁸ mol/L) limits.

Conclusions:

• The developed voltammetric method offers a sensitive and accurate approach for CU determination.
• The method demonstrated high recovery rates (99.28 ± 2.04%) in real-world samples (dietary supplements).
• This provides a valuable tool for quality control and research involving curcumin.