3.2. Authentic Standards
Eriodictyol (CAS No. 552-58-9), luteolin (CAS No. 491-70-3), luteolin-7-Stock solutions (1 mg/mL) for quantitative analysis were made by dissolving 2–5 mg of flavonoid in 2–5 mL of methanol. Working standard solutions in the range of 10–250 g/mL (6 measurement points for each pattern) were prepared by mixing with 50% aq. methanol (