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

Table 1 Recovery (%) of α-CyD-5-ASA, 5-ASA and Ac-5-ASA in the GIT, plasma, urine, feces, and liver after oral administration of α-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	19.8±4.8	0.0±0.0	0.0±0.0	41.6±30.8	0.0±0.0	0.0±0.0	7.7±7.6	14.7±17.3	7.3±12.6	6.3±11.0	0.8±1.0	1.8±1.6
8	2.8±4.3	0.0±0.0	0.0±0.0	14.3±6.5	0.7±0.4	0.0±0.0	11.3±14.0	20.2±22.4	6.1±5.8	7.2±9.9	9.1±7.7	18.4±13.6
12	0.0±0.0	0.1±0.1	0.4±0.5	1.7±0.4	0.5±0.7	2.5±3.9	9.4±11.8	4.7±7.4	6.2±6.4	17.2±24.0	17.3±23.7	16.6±17.9
24	0.0±0.0	0.0±0.0	0.0±0.0	0.0±0.0	0.0±0.0	22.8±24.2	9.2±9.0	0.3±0.5	7.9±13.6	13.3±15.6	1.4±1.1	23.4±15.6
	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	69.3±29.0
8	0.0±0.0	0.5±0.3	4.0±2.6	0.0±0.0	0.2±0.1	2.0±1.3	0.0±0.0	0.0±0.0	0.0±0.0	0.0±0.0	0.3±0.1	3.0±2.2	65.0±11.9
12	0.0±0.0	0.4±0.5	4.7±4.0	0.0±0.0	0.3±0.4	2.8±2.4	0.3±0.5	7.1±8.2	7.1±8.0	0.0±0.0	0.2±0.3	0.4±0.8	50.5±20.0
24	0.0±0.0	1.4±1.2	1.9±1.9	0.0±0.0	0.0±0.0	0.0±0.0	4.3±7.4	1.3±1.3	9.3±11.8	0.0±0.0	1.4±1.3	2.1±2.5	12.6±7.6

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.