Table 2.

Validations among ELISA runs for the analysis of rhein.

Rhein (ng/mL)	RSD (%)
	Intra-assay	Interassay
0	3.41	6.84
1.00	0.38	0.64
0.50	1.31	0.70
0.25	0.65	0.86
0.16	2.73	3.59
0.06	1.92	3.87
0.03	4.30	4.20
0.02	2.13	3.53