Colon-specific drug delivery systems based on cyclodextrin prodrugs: In vivo evaluation of 5-aminosalicylic acid from its cyclodextrin conjugates

Table 2 Recovery (%) of β-CyD-5-ASA, 5-ASA, and Ac-5-ASA in GIT, plasma, urine, feces, and liver after oral administration of 9 9 β-CyD-5-ASA to rats (mean±SD)

Time	Stomach			Small intestine			Cecum			Colon
(h)	Prodrug	5-ASA	AC-5-ASA	Prodrug	5-ASA	AC-5-ASA	Prodrug	5-ASA	AC-5-ASA	Prodrug	5-ASA	AC-5-ASA
4	26.7±3.2	0.0±0.0	0.0±0.0	47.0±27.6	0.0±0.0	0.0±0.0	13.2±13.7	1.0±0.6	0.3±0.3	9.7±16.9	1.2±1.4	0.9±1.4
8	8.5±12.9	0.0±0.0	0.0±0.0	14.9±6.6	2.4±3.4	0.0±0.0	30.6±35.8	7.5±11.6	3.8±3.8	12.3±17.0	9.1±4.4	4.3±2.9
12	0.0±0.0	0.0±0.0	0.7±1.2	6.6±7.9	0.4±0.3	3.0±0.8	8.4±7.4	18.7±13.1	11.7±12.8	16.1±12.6	13.5±12.4	7.9±7.3
24	0.0±0.0	0.0±0.0	0.0±0.0	0.0±0.0	0.0±0.0	2.9±4.4	16.6±16.1	10.3±16.7	17.4±15.2	27.2±45.2	11.0±12.9	5.3±5.9
	Plasma			Urine			Feces			Liver			Total
	Prodrug	5-ASA	AC-5-ASA	Prodrug	5-ASA	AC-5-ASA	Prodrug	5-ASA	AC-5-ASA	Prodrug	5-ASA	AC-5-ASA	recovery
4	0.0±0.0	0.0±0.0	0.0±0.0	0.0±0.0	0.0±0.0	0.0±0.0	0.0±0.0	0.0±0.0	0.0±0.0	0.0±0.0	0.0±0.0	0.0±0.0	64.0±14.3
8	0.0±0.0	0.7±0.7	2.4±3.0	0.0±0.0	0.1±0.0	0.4±0.4	0.0±0.0	0.1±0.0	0.1±0.1	0.0±0.0	1.9±2.5	1.1±1.6	40.6±14.7
12	0.0±0.0	1.2±0.5	4.1±4.6	0.0±0.0	2.4±3.5	2.3±2.2	0.3±0.9	0.0±0.0	1.1±1.8	0.0±0.0	0.5±0.7	0.8±1.2	35.6±10.7
24	0.0±0.0	2.3±2.6	1.7±2.2	0.0±0.0	0.0±0.0	0.0±0.0	4.6±7.9	0.2±0.2	0.7±0.9	0.0±0.0	0.0±0.0	0.0±0.0	14.8±6.5

Total recovery=100×(amount of the intact prodrugs, 5-ASA, and Ac-5-ASA recovered from stomach, small intestine, cecum, colon, blood, urine, liver, and feces)/dose.