Determination of flavonoids in plant material by HPLC with diode-array and electro-array detections

Area of Science:

• Analytical Chemistry
• Food Science
• Phytochemistry

Background:

• Flavonoids are vital plant compounds with significant health benefits.
• Accurate quantification of flavonoids in food is crucial for nutritional analysis and quality control.
• Existing methods may lack the sensitivity or specificity for comprehensive flavonoid profiling.

Purpose of the Study:

• To develop and validate a robust analytical method for identifying and quantifying multiple flavonoids in plant-derived foods.
• To establish a sensitive and reliable technique for routine analysis of catechins and other flavonoid classes.

Main Methods:

• A high-performance liquid chromatographic (HPLC) system coupled with diode-array detection (DAD) and electro-array (EC) detection was employed.
• Catechins were extracted using ethyl acetate and quantified via EC detection.
• Other flavonoids were quantified using DAD following acid hydrolysis.

Main Results:

• The developed HPLC-DAD-EC method successfully identified and quantified 17 flavonoids in plant-derived foods.
• Detection systems exhibited excellent linearity (R² > 0.999) within the evaluated ranges (20-200 ng/injection for DAD, 20-100 ng/injection for EC).
• Method validation demonstrated good precision (CV < 10.5%) and acceptable recoveries (70-124%), with peak purity confirmed by combined spectral and voltammetric data.

Conclusions:

• The combined HPLC-DAD-EC method provides an effective and reliable approach for the determination of catechins and other flavonoids in various plant-based food matrices.
• This validated method ensures accurate nutritional assessment and quality control of flavonoid content in food products.
• The technique's sensitivity, linearity, and peak purity confirmation make it suitable for comprehensive flavonoid analysis.