Table 2.

Validation data for cardiac glycosides in culinary herbs.

Analyte	Reporting Limit (ng/g)	Linear Range (ng/g)	R2	Concentration Level	Recovery ± SD1	Repeatability (RSDr) (%)	Reproducibility (RSDwR) (%)	Measurement Uncertainty
				(ng/g)	(%)			(%)
Oleandrin	2.5	2.5–200	0.9993	5	82 ± 7	7	8	17
				25	86 ± 6	6	7	14
				100	80 ± 6	6	7	15
					Mean: 83 ± 6	Mean: 6	Mean: 8
Digoxin	10	10–400	0.9995	10	121 ± 11	11	11	21
				50	114 ± 7	7	7	13
				200	111 ± 10	6	10	19
					Mean: 115 ± 10	Mean: 9	Mean: 9
Digitoxin	20	20–400	0.9995	20	86 ± 10	14	14	27
				100	96 ± 11	9	12	24
				400	95 ± 13	7	15	31
					Mean: 92 ± 12	Mean: 10	Mean: 14
Convallatoxin	10	10–400	0.9994	10	52 ± 7	7	14	28
				50	55 ± 9	12	17	34
				200	57 ± 7	10	12	25
					Mean: 55 ± 7	Mean: 9	Mean: 14

¹ SD: Standard deviation.