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Visualization of delayed release of compounds from pH-sensitive capsulesin vitroandin vivoin a hamster model
- Source :
- Contrast Media & Molecular Imaging. 11:24-31
- Publication Year :
- 2015
- Publisher :
- Wiley, 2015.
-
Abstract
- Delayed controlled release is an innovative strategy to locally administer therapeutic compounds (e.g. chemotherapeutics, antibodies etc.). This would improve efficiency and reduce side effects compared with systemic administration. To enable the evaluation of the efficacy of controlled release strategies both in vitro and in vivo, we investigated the release of contrast agents (19 F-FDG and BaSO4) to the intestinal tract from capsules coated with pH-sensitive polymers (EUDRAGIT L-100) by using two complementary techniques, i.e. 19 F magnetic resonance imaging (MRI) and computed tomography (CT). Using in vitro 19 F-MRI, we were able to non-destructively and dynamically establish a time window of 2 h during which the capsules are resistant to low pH. With 19 F-MRI, we could establish the exact time point when the capsules became water permeable, before physical degradation of the capsule. This was complemented by CT imaging, which provided longitudinal information on physical degradation of the capsule at low pH that was only seen after 230 min. After oral administration to hamsters, 19 F-MRI visualized the early event whereby the capsule becomes water permeable after 2 h. Additionally, using CT, the integrity and location (stomach and small intestines) of the capsule after administration could be monitored. In conclusion, we propose combined 19 F-MRI and CT to non-invasively visualize the different temporal and spatial events regarding the release of compounds, both in an in vitro setting and in the gastrointestinal tract of small animal models. This multimodal imaging approach will enable the in vitro and in vivo evaluation of further technical improvements to controlled release strategies. Copyright © 2015 John Wiley & Sons, Ltd.
- Subjects :
- 0301 basic medicine
Gastrointestinal tract
Pathology
medicine.medical_specialty
medicine.diagnostic_test
business.industry
Capsule
Magnetic resonance imaging
Controlled release
In vitro
03 medical and health sciences
030104 developmental biology
In vivo
Oral administration
Systemic administration
Medicine
Radiology, Nuclear Medicine and imaging
business
Biomedical engineering
Subjects
Details
- ISSN :
- 15554309
- Volume :
- 11
- Database :
- OpenAIRE
- Journal :
- Contrast Media & Molecular Imaging
- Accession number :
- edsair.doi...........6edc869a405b7879b30d42f33bd089d2