Table 2.

Validation parameters of the GC-FID method of determining harmane, norharmane and 4,4′-dihydroxybiphenyl based on silylation

Compounds	Linearity range (μg mL−1)	Reggresion equation	Correlation coefficient	Accuracy (%)	Intra-day precision RSD (%)	LOQinst (ng)	LODinst (ng)
Harmane	5–80	125427c–281899	0.992	86.7–112.4	<3.76	6	2
Norharmane	5–125	194739c–657395	0.997	89.15–109.12	<2.49	6	2
4,4′-Dihydroxybiphenyl	0.25–125	267004c–16993	0.996	86.84–113.97	<2.27	0.5	0.17