SPE-UHPLC-FLD Method for the Simultaneous Determination of Five Anthraquinones in Human Urine Using Mixed-Mode Bis(tetraoxacalix[2]arene[2]triazine) Modified Silica as Sorbent

Table 2

The interday and intraday precision and recoveries of the method.

Analytes	Spiked amount (ng/g)	Intraday ()		Interday ()
		Recovery (%)	RSD (%)	Recovery (%)	RSD (%)
Aloe-emodin	20	97.3	2.26	96.7	2.88
	100	96.8	2.58	97.5	3.15
	500	95.2	2.42	94.8	3.36
Rhein	20	104.3	2.03	102.8	3.28
	100	97.5	2.83	98.1	2.95
	500	96.3	2.78	97.4	3.45
Emodin	20	105.6	2.75	106.6	3.47
	100	96.7	2.63	95.8	4.58
	500	94.9	2.86	95.4	3.48
Chrysophanol	20	97.7	2.05	98.0	2.85
	100	98.3	2.83	97.7	3.15
	500	95.8	2.75	96.2	3.42
Physcion	20	104.6	2.46	105.6	4.03
	100	95.8	2.94	96.3	3.85
	500	96.8	2.81	96.4	3.07