Table 4.

Validation parameters obtained in the optimized LC-MS method (n = 5).

Compound	LOD (ng/mL)	LOQ (ng/mL)	R2	Calibration Curve Equation	Linearity Range (µg/mL)
GA	0.52	1.56	0.9990	y = 2.4 × 107x − 1.2 × 106	0.030–30
EGCG	0.46	1.38	0.9988	y = 4.6 × 107x − 2.8 × 106	0.015–35
EGC	0.42	1.26	0.9987	y = 6.0 × 107x − 1.9 × 106	0.020–40
ECG	0.42	1.26	0.9992	y = 6.6 × 107x − 1.2 × 106	0.015–40
EC	0.42	1.26	0.9994	y = 7.8 × 108x + 3.3 × 105	0.010–40