Table 5.

24 h storage at room temperature stability, three freeze-thaw cycles stability and long-term stability of eleven compounds (n = 6).

Compound	Concentration (ng mL−1)	Freeze-thaw cycles		At −20°C for 1 weeks		Autosampler for 24 h
		Remains (%)	RSD (%)	Remains (%)	RSD (%)	Remains (%)	RSD (%)
Paeoniflorin	7.5	93.7	14	101	8.8	95.8	15
	75	88.0	8.6	85.8	9.5	97.4	6.4
	750	106	5.0	96.5	13	89.9	11
Ecdysterone	15	97.1	11	102	11	94.2	8.4
	150	95.5	14	107	11	102	7.0
	1500	95.0	8.0	103	12	93.1	6.2
Amygdalin	30	87.0	10	93.0	7.2	98.1	9.0
	300	87.9	12	105	14	94.2	15
	3000	103	10	94.1	13	92.6	12
Mulberroside A	30	104	11	112	12	86.6	10
	300	94.4	14	106	5.7	87.7	9.9
	3000	96.5	9.9	97.2	13	95.3	9.3
Caffeic acid	30	106	8.5	95.8	13	103	8.9
	300	85.6	14	101	11	89.9	12
	3000	89.2	3.5	90.5	11	85.2	7.7
Ferulic acid	15	111	11	105	9.7	107	12
	150	108	11	111	11	93.2	8.7
	1500	99.6	4.1	106	7.5	95.0	7.7
Salvianolic acid B	30	97.1	11	113	13	91.7	6.4
	300	105	8.8	92.6	9.4	99.9	12
	3000	101	12	100	13	108	8.5
Astragaloside IV	30	111	4.7	113	6.7	86.3	10
	300	103	4.1	108	8.8	101	12
	3000	95.4	10	97.4	14	96.1	14
Formononetin	0.75	94.5	6.2	111	8.6	102	13
	7.5	89.9	12	88.9	6.6	111	12
	75	90.0	9.0	106	1.8	108	8.1
Cryptotanshinone	3	104	12	112	8.7	87.2	13
	30	106	10	93.2	8.5	85.2	12
	300	107	9.0	109	11	87.5	12
Tanshinone IIA	0.75	99.0	4.9	93.0	10	88.4	12
	7.5	114	9.1	105	14	94.9	9.0
	75	106	10	94.1	15	93.6	11