Development of an Enzyme-Linked Immunosorbent Assay Method for the Detection of Rhein in Rheum officinale

Table 1

Cross reactivities of mAb1F8 against various compounds.

Compound	Structure	IC50 (μg L^−1)	CR (%)
Rhein		0.044	100
Aloe-emodin		0.162	27
Emodin		4.946	0.9
Chrysophanol		14.144	0.3
Physcion		50.710	0.1
Sennoside A		1393.901	0.005
Sennoside B		—^a	<0.001
Rhaponticin		—	<0.001

^aNo inhibition was observed at up to 20,000 μg L⁻¹ of the compound.