title: The Combined Use of Imaging Approaches to Assess Drug Release from Multicomponent Solid Dispersions.
abstract: Imaging methods were used as tools to provide an understanding of phenomena that occur during dissolution experiments, and ultimately to select the best ratio of two polymers in a matrix in terms of enhancement of the dissolution rate and prevention of crystallization during dissolution.
  
  
  
  Magnetic resonance imaging, ATR-FTIR spectroscopic imaging and Raman mapping have been used to study the release mechanism of a poorly water soluble drug, aprepitant, from multicomponent amorphous solid dispersions. Solid dispersions were prepared based on the combination of two selected polymers - Soluplus, as a solubilizer, and PVP, as a dissolution enhancer. Formulations were prepared in a ratio of Soluplus:PVP 1:10, 1:5, 1:3, and 1:1, in order to obtain favorable properties of the polymer carrier.
  
  
  
  The crystallization of aprepitant during dissolution has occurred to a varying degree in the polymer ratios 1:10, 1:5, and 1:3, but the increasing presence of Soluplus in the formulation delayed the onset of crystallization. The Soluplus:PVP 1:1 solid dispersion proved to be the best matrix studied, combining the abilities of both polymers in a synergistic manner.
  
  
  
  Aprepitant dissolution rate has been significantly enhanced. This study highlights the benefits of combining imaging methods in order to understand the release process.
authors: Department of Chemical Engineering, University of Chemistry and Technology Prague, Prague 6, Czech Republic.|Zentiva, k.s, U Kabelovny 130, Prague 10, Czech Republic.
authors: Kateřina
authors: K
authors: Punčochová
authors: Department of Chemical Engineering, Imperial College London, South Kensington Campus, London, SW7 2AZ, UK.
authors: Andrew V
authors: AV
authors: Ewing
authors: Department of Chemical Engineering, University of Chemistry and Technology Prague, Prague 6, Czech Republic.
authors: Michaela
authors: M
authors: Gajdošová
authors: Zentiva, k.s, U Kabelovny 130, Prague 10, Czech Republic.
authors: Tomáš
authors: T
authors: Pekárek
authors: Zentiva, k.s, U Kabelovny 130, Prague 10, Czech Republic.
authors: Josef
authors: J
authors: Beránek
authors: Department of Chemical Engineering, Imperial College London, South Kensington Campus, London, SW7 2AZ, UK. s.kazarian@imperial.ac.uk.
authors: Sergei G
authors: SG
authors: Kazarian
authors: Department of Chemical Engineering, University of Chemistry and Technology Prague, Prague 6, Czech Republic. Frantisek.Stepanek@vscht.cz.
authors: František
authors: F
authors: Štěpánek
mesh_terms: D000077608:Aprepitant; D002626:Chemistry, Pharmaceutical / Q000379:methods; D003460:Crystallization; D004337:Drug Carriers / Q000737:chemistry; D065546:Drug Liberation; D008279:Magnetic Resonance Imaging / Q000379:methods; D009025:Morpholines / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D011145:Polyvinyls / Q000737:chemistry*; D011759:Pyrrolidines / Q000737:chemistry*; D012995:Solubility; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods; D014867:Water / Q000737:chemistry
chemical_list: D004337:Drug Carriers; D009025:Morpholines; D011108:Polymers; D011145:Polyvinyls; D011759:Pyrrolidines; C505150:poly(N-vinylpyrrolidine); C572167:polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer; D014867:Water; D000077608:Aprepitant; D011092:Polyethylene Glycols
keywords: FT-IR spectroscopic imaging; amorphous solid dispersion; confocal Raman spectroscopy; crystallisation; magnetic resonance imaging