An LC-MS/MS Method for Simultaneous Determination of the Toxic and Active Components of Cortex Periplocae in Rat Plasma and Application to a Pharmacokinetic Study

Table 2

Stability of analytes.

Compounds	Concentration (ng/mL)	Working solution		Autosampler for 24 hours		Room temperature for 24 h		Freeze thaw cycles		-80°C for 1 month
		Accuracy (%)	RSD (%)	Accuracy (%)	RSD (%)	Accuracy (%)	RSD (%)	Accuracy (%)	RSD (%)	Accuracy (%)	RSD (%)
isovanillin	7.2	104	4.27	100	2.31	107	7.01	101	1.97	109	7.54
	120	96.1	4.79	112	1.88	106	2.57	98.6	1.80	100	5.58
	1200	85.0	3.77	114	3.19	103	2.13	107	2.32	99.4	7.46
scopoletin	1.44	103	1.29	104	4.19	96.8	6.45	104	2.36	108	8.17
	24	109	4.24	105	3.30	115	4.27	110	2.74	108	5.42
	240	97.3	4.90	97.1	1.74	103	1.01	100	2.72	96.4	5.79
periplocin	7.2	103	1.92	113	1.65	111	8.33	93.7	6.72	115	8.62
	120	98.9	4.58	109	4.02	116	1.80	114	9.17	115	9.91
	1200	94.4	4.41	113	1.60	96.4	4.23	113	2.53	92.9	6.10
periplogenin	1.44	111	1.80	108	3.12	92.6	4.17	116	4.69	109	7.47
	24	99.4	3.71	110	3.69	115	5.21	112	3.25	108	3.45
	240	81.5	2.68	104	4.19	101	2.04	92.8	2.68	98.7	5.48
periplocymarin	1.44	110	3.13	101	4.71	107	5.14	113	5.91	106	7.77
	24	95.1	4.41	108	5.38	102	5.85	113	1.74	102	3.27
	240	84.2	1.73	102	4.27	98.5	1.99	103	2.28	102	5.81