Visualising Tablet Dissolution: Measurement of Hydration and Drug Release

摘要

Magnetic Resonance Imaging (MRI) measures the hydration of tablets during dissolution by non-invasively mapping ~(1)H nuclei associated with "mobile" water. Images acquired on the PharmaSense Tablet Dissolution Imager with integrated US Pharmacopeia 4 apparatus, provide key data for the formulation chemist. Furthermore, simultaneous measurement of the drug concentration in the outflow by on-line UV analysis allows comparison of the drug release profile against the rate of water ingress. Most studies of tablet dissolution are characterised by a drug release profile which is determined by collecting aliquots of the outflow, usually analysed off-line for the active pharmaceutical ingredient (API). However, controlled release pharmaceuticals are being developed with an increasing degree of complexity and are difficult to characterise using API analyses alone. They are typically a composite and therefore the rate of drug release could be dependent on a number of different factors including the excipients and coatings used as well as the geometry of the tablet.