A Sensitive and Efficient Method for Determination of Capecitabine and Its Five Metabolites in Human Plasma Based on One-Step Liquid-Liquid Extraction

Table 5

Recovery, matrix effect, and stability of Cap and its five metabolites (%).

		Cap	5’-DFCR	5’-DFUR	2’-DFUR	5-FU	FUH2	5-ClU	Fdb
Frozen-thaw stability	Low	93.25	95.23	98.35	100.57	97.35	93.34	—	—
	High	95.12	93.13	96.56	86.87	87.23	99.31	—	—
24 h in autosampler	Low	99.52	101.91	113.92	110.25	109.94	100.33	—	—
	High	94.62	114.62	114.04	112.53	100.04	108.73	—	—
Long-term stability (3 months)	Low	95.23	96.32	106.15	102.53	106.78	101.45	—	—
	High	98.55	95.65	110.25	112.25	96.25	105.22	—	—
Recovery	Low	90.15	80.89	70.26	59.27	64.39	88.50	87.30	91.64
	High	85.26	80.89	70.26	59.86	76.82	82.12
	RSD	3.69	3.04	4.51	4.51	10.39	3.42	—	—
Matrix effect	Low	114.48	110.24	106.62	106.93	74.84	94.14	106.10	60.91
	High	108.94	109.08	106.31	105.63	83.55	93.00
	RSD	3.84	2.70	4.39	3.87	5.69	4.78	—	—

RSD was calculated using the IS-normalized matrix and recovery factors.