Table 3. Validation parameters of the chromatographic method used for determining phenolic acids.

Phenolic acid	γ/(μg/mL) Detection limit Linearity		R2	k	α
Gallic	0.12	0.36–3.6	0.998	5.4
					1.35
Protocatechuic	0.27	0.81–8.1	0.999	7.3
					1.25
Chlorogenic	0.41	1.23–12.3	0.999	9.2
					1.17
Hydroxybenzoic	0.32	0.96–9.6	0.999	10.7
					1.18
Caffeic	0.24	0.72–7.2	0.999	12.6
					1.13
Syringic	0.25	0.75–7.5	0.999	14.2
					1.14
Vanillin	0.18	0.54–5.4	0.999	16.2
					1.32
Coumaric	0.19	0.57–5.7	0.999	21.4
					1.24
Ferulic	0.25	0.75–7.5	0.999	26.6

k=retention factor, α=separation factor