X-ray Microtomography of Solid Dosage Forms

X-ray microtomography has great potential for improving the understanding of the structural features of solid dosage forms and the changes in those features during manufacturing, handling, and storage. This article describes the basic principles of the technique and provides examples of its potential applications. harmaceutical scientists have long sought the ability to see inside the solid dosage forms they produce to determine their products’ structural features and to better understand their mode of action. Previous studies have used various techniques for visualizing the internal structure of solid dosage forms, including H NMR imaging (1), confocal microscopy (2), and conventional microscopy (optical and electron) combined with mechanical slicing of samples (i.e., microtoming) (3). One drawback of several current techniques is their invasive nature that can destroy the sample and prevent any further testing. Another is the techniques’ limited penetration and resolution. Thus, it is probably fair to say that the ideal experimental approach for the three-dimensional structural imaging of pharmaceutical dosage forms has not yet been realized. X-ray microtomography is a relatively new approach to imaging the internal structure of solid dosage forms. This technique has been widely used for the in vivo imaging of plants, insects, animals, and humans. X-ray microtomography is a nondestructive technique that has a high penetration ability and provides a reasonable level of resolution (~5–20 mm).