Stabilization of the Amorphous Structure of Spray-Dried Drug Nanoparticles
Year: 2016
Type: article
Abstract: The bioavailability of hydrophobic drugs strongly increases if they are formulated as amorphous materials because the solubility of the amorphous phase is much higher than that of the crystal. Moreover, the stability of these particles against crystallization during storage increases with decreasing particle size. Hence, it is advantageous to formulate poorly water soluble drugs as amorphous nanoparticles. The formulation of an amorphous structure is often difficult because many of these drugs have a high propensity to crystallize. This difficulty can be overcome if drugs are spray-dried using a microfluidic nebulator we recently developed. However, these nanoparticles agglomerate when they come in contact with each other, and this compromises the stability of their amorphous structure through crystallization. To improve their stability, we coat the nanoparticles with a sterically stabilizing polymer layer; this can be accomplished by co-spraying them with an excipient. However, this excipient must meet strict solubility limits, which severely limit the choice of polymers. Alternatively, the nanoparticles can be sterically stabilized by spraying them directly into a polymeric matrix; this enables a much wider choice of stabilizing polymers.
Authors: Esther Amstad, Frans Spaepen, David A. Weitz
Institutions: École Polytechnique Fédérale de Lausanne, Harvard University
Language: English
Subfield: Pharmaceutical Science
Domain: Life Sciences
Open Access status: green
Funder: Division of Materials Research
Awards: G1020486556, G1637850186
OpenAlex ID: W2493365531