Steingoetter Andreas, Weishaupt Dominik, Kunz Patrick, Mäder Karsten, Lengsfeld Hans, Thumshirn Miriam, Boesiger Peter, Fried Michael, Schwizer Werner
Biophysics Group, Institute of Biomedical Engineering, University and ETH Zurich Gloriastrasse, 35 CH-8092 Zurich, Switzerland.
Pharm Res. 2003 Dec;20(12):2001-7. doi: 10.1023/b:pham.0000008049.40370.5a.
To develop a magnetic resonance imaging (MRI) technique for assessing in vivo properties of orally ingested gastric-retentive tablets under physiologic conditions.
Tablets with different floating characteristics (tablet A-C) were marked with superparamagnetic Fe3O4 particles to analyze intragastric tablet position and residence time in human volunteers. Optimal Fe3O4 concentration was determined in vitro. Intragastric release characteristic of one slow-release tablet (tablet D) was analyzed by embedding gadolinium chelates (Gd-DOTA) as a drug model into the tablet. All volunteers underwent MRI in the sitting position. Tablet performance was analyzed in terms of relative position of tablet to intragastric meal level (with 100% at meal surface), intragastric residence time (min) and Gd-DOTA distribution volume (% of meal volume).
Intragastric tablet floating performance and residence time of tablets (tablet A-D) as well as the intragastric Gd-DOTA distribution of tablet D could be monitored using MRI. Tablet floating performance was different between the tablets (A, 93%(95 - 9%); B, 80%(80 - 68%): C, 38%(63 - 32%); p < 0.05). The intragastric distribution volume of Gd-DOTA was 19.9% proximally and 35.5% distally.
The use of MRI allows the assessment of galenic properties of orally ingested tablets in humans in seated position.
开发一种磁共振成像（MRI）技术，用于评估生理条件下口服胃滞留片的体内特性。
用超顺磁性Fe3O4颗粒标记具有不同漂浮特性的片剂（片剂A - C），以分析人体志愿者胃内片剂位置和滞留时间。在体外确定最佳Fe3O4浓度。通过将钆螯合物（Gd - DOTA）作为药物模型包埋到一片缓释片中（片剂D），分析其胃内释放特性。所有志愿者均以坐姿接受MRI检查。根据片剂相对于胃内食物水平的相对位置（食物表面为100%）、胃内滞留时间（分钟）和Gd - DOTA分布体积（食物体积的百分比）来分析片剂性能。
使用MRI可以监测胃内片剂的漂浮性能和片剂（片剂A - D）的滞留时间以及片剂D的胃内Gd - DOTA分布。各片剂的漂浮性能不同（A，93%（95 - 9%）；B，80%（80 - 68%）；C，38%（63 - 32%）；p < 0.05）。Gd - DOTA在胃内的分布体积近端为19.9%，远端为35.5%。
使用MRI能够评估人体坐姿下口服片剂的药剂学性质。
