Detection of Total Phenol in Green and Black Teas by Flow Injection System and Unmodified Screen Printed Electrode

Table 2

Parameters of regression for phenolic compounds.

Phenolic compounds	Linear range (μg/mL)	Equation	Correlation, 𝑅^2
Gallic acid	5.0–25.0	−0.016+0.007𝑥	0.9818
	50.0–100.0	−0.047+0.003𝑥	0.9948
EGCG	12.5–100.0	−0.005+0.021𝑥	0.9976
EC	12.5–100.0	−0.0002+0.023𝑥	0.9710
ECG	12.5–100.0	0.003+0.022𝑥	0.9982
EGC	12.5–100.0	0.008+0.022𝑥	0.9919

For the interval 5.0–25.0, the concentration of K₃Fe(CN)₆ was 1.0 mM; for the others, the concentration of K₃Fe(CN)₆ was 2.0 mM.