Impact of Drying on Solid State Modifications and Drug Distribution in Ibuprofen-Loaded Calcium Stearate Pellets

Abstract

Drying is a common pharmaceutical process, whose potential to alter the final drug properties-even at relatively low temperatures-is often neglected. The present study addresses the impact of drying at 20 and 50 °C on wet-extruded calcium stearate (CaSt) pellets. Drying at 20 °C caused the majority of ibuprofen to accumulate at the pellet surface due to a strong convective flow from the pellet's center to the surface. In contrast, pellets dried at 50 °C still contained ibuprofen in the pellet's interior due to the higher drying rate and the associated film breakage during drying. Moreover, the higher drying temperature caused CaSt to form a second lamellar phase and ibuprofen to convert (partly) into its amorphous state. Overall, the drying process affected the solid state and the spatial ibuprofen distribution within the pellet. Knowledge of these effects can aid in tailoring advanced multipellet formulations.

Crystallographic Textures and Morphologies of Solution Cast Ibuprofen Composite Films at Solid Surfaces

“…In addition, the samples show more elongated structures, which are typically for crystalline Ibu. 29 Using an equal amount of Ibu and PS results in a strong deviation of the morphology with now larger elongated structures being present. A small scratch in the sample is made to reveal the average layer thickness of the sample; a line scan in this area shows an average film height of 320 nm from the surface.…”

“…The 300 reflection is absent in accordance with the known crystal structure with the monoclinic unit cell, a = 1.439 nm, b = 0.78 nm, c = 1.05 nm and α = γ = 90° and β = 99.7° in the space group P 21/ c . 29 …”

Strategies for Drug Encapsulation and Controlled Delivery Based on Vapor‐Phase Deposited Thin Films

“…Ever since medications were used, excipients are employed . Especially, the usage of macromolecules or polymers as fillers, gliding agent, disintegration agent, or protective coatings allow the preparation of solid state formulations like tablets, pellets, or powders. Developments in nanomaterial chemistry have enabled the proliferation of different types of drug carriers, for example, polymer–drug conjugates, nanoparticles, nanoclusters, micelles, dendritic polymer carriers, nanocapsules, and nanoemulsions .…”

Wrinkle formation in a polymeric drug coating deposited via initiated chemical vapor deposition

“…This is generally achieved by biocompatible polymer/drug composite layers or by dispersing the drug itself within a soluble or insoluble polymer matrix, thus forming a solid-state dispersion or solution. 3 , 4 …”