Use of ultrasound imaging and fluoroscopic imaging to study gastric retention of enzyme-digestible hydrogels

摘要: Abstract Ultrasound and fluoroscopic imaging techniques were used to monitor the gastric retention of enzyme-digestible hydrogels in canine stomach. When water was present stomach, ultrasound very effective monitoring position hydrogel solvent penetration into gel, tissue-gel interactions during peristalsis. Rubbery or fully swollen appeared as sonolucent objects with imaging. Partially displayed a outer layer due centrally located bright echo resulting from acoustic impedance mismatch at glassy/ rubbery interface. The degree peristalsis inversely related extent lumenal distention water. effectiveness peristaltic contractions driving toward pyloric sphincter increased emptied In absence water, gel became difficult. For this reason, gels loaded diatrizoate meglumine/sodium visualize real-time using Fluoroscopic allowed only indirect assessment movement swelling. under fasted conditions influenced by deformation response contractions. Hydrogels low showed long times. utilization for dynamic events stomach provided information on properties which are important retention. use these development long-term oral drug delivery systems is described.