AIM: To evaluate, using isotope techniques, the in vivo effectiveness of a pH-dependent colonic delivery system. METHODS: In order to dispose of differently labelled substrates for measurement of orocaecal transit time, inulin-14C-carboxylic acid was evaluated as an alternative substrate to inulin and lactose-13C-ureide. Secondly, the time of release of 13C- and 15N-urea from the colonic delivery system was compared with the orocaecal transit time, measured using inulin and inulin-14C-carboxylic acid. This study was repeated after a 2-week lactulose intake period. RESULTS: The orocaecal transit time determined using inulin-14C-carboxylic acid (398 min) was not significantly different from the orocaecal transit time determined using inulin (420 min) or lactose-13C-ureide (396 min). Before lactulose intake, the 13CO2 excretion time was 358 min and the orocaecal transit times determined with the inulin-14C-carboxylic acid and inulin breath test were 376 and 375 min respectively. After lactulose, the 13CO2 excretion time was 383 min and orocaecal transit times were 354 min for inulin-14C-carboxylic acid and 392 min for inulin. A highly significant correlation was found. Good agreement was found between the urinary 15N excretion and the appearance of 13CO2 in breath. CONCLUSION: Isotope techniques provide an excellent non-invasive tool for the in vivo evaluation of a colonic delivery system.
AIM: To evaluate, using isotope techniques, the in vivo effectiveness of a pH-dependent colonic delivery system. METHODS: In order to dispose of differently labelled substrates for measurement of orocaecal transit time, inulin-14C-carboxylic acid was evaluated as an alternative substrate to inulin and lactose-13C-ureide. Secondly, the time of release of 13C- and 15N-urea from the colonic delivery system was compared with the orocaecal transit time, measured using inulin and inulin-14C-carboxylic acid. This study was repeated after a 2-week lactulose intake period. RESULTS: The orocaecal transit time determined using inulin-14C-carboxylic acid (398 min) was not significantly different from the orocaecal transit time determined using inulin (420 min) or lactose-13C-ureide (396 min). Before lactulose intake, the 13CO2 excretion time was 358 min and the orocaecal transit times determined with the inulin-14C-carboxylic acid and inulin breath test were 376 and 375 min respectively. After lactulose, the 13CO2 excretion time was 383 min and orocaecal transit times were 354 min for inulin-14C-carboxylic acid and 392 min for inulin. A highly significant correlation was found. Good agreement was found between the urinary 15N excretion and the appearance of 13CO2 in breath. CONCLUSION: Isotope techniques provide an excellent non-invasive tool for the in vivo evaluation of a colonic delivery system.
Authors: Reinout C A Schellekens; Frans Stellaard; Herman J Woerdenbag; Henderik W Frijlink; Jos G W Kosterink Journal: Br J Clin Pharmacol Date: 2011-12 Impact factor: 4.335
Authors: R C A Schellekens; G G Olsder; S M C H Langenberg; T Boer; H J Woerdenbag; H W Frijlink; J G W Kosterink; F Stellaard Journal: Br J Pharmacol Date: 2009-09 Impact factor: 8.739
Authors: Eef Boets; Sara V Gomand; Lise Deroover; Tom Preston; Karen Vermeulen; Vicky De Preter; Henrike M Hamer; Guy Van den Mooter; Luc De Vuyst; Christophe M Courtin; Pieter Annaert; Jan A Delcour; Kristin A Verbeke Journal: J Physiol Date: 2016-09-18 Impact factor: 5.182