title: The effects of polymer carrier, hot melt extrusion process and downstream processing parameters on the moisture sorption properties of amorphous solid dispersions.
abstract: OBJECTIVE
  The aim of this study was to evaluate the effect of polymer carrier, hot melt extrusion and downstream processing parameters on the water uptake properties of amorphous solid dispersions.
  
  
  METHODS
  Three polymers and a model drug were used to prepare amorphous solid dispersions utilizing the hot melt extrusion technology. The sorption-desorption isotherms of solid dispersions and their physical mixtures were measured by the dynamic vapour sorption system, and the effects of polymer hydrophobicity, hygroscopicity, molecular weight and the hot melt extrusion process were investigated. Fourier transform infrared (FTIR) imaging was performed to understand the phase separation driven by the moisture.
  
  
  RESULTS
  Solid dispersions with polymeric carriers with lower hydrophilicity, hygroscopicity and higher molecular weight could sorb less moisture under the high relative humidity (RH) conditions. The water uptake ability of polymer-drug solid dispersion systems were decreased compared with the physical mixture after hot melt extrusion, which might be due to the decreased surface area and porosity. The FTIR imaging indicated that the homogeneity of the drug molecularly dispersed within the polymer matrix was changed after exposure to high RH.
  
  
  CONCLUSIONS
  Understanding the effect of formulation and processing on the moisture sorption properties of solid dispersions is essential for the development of drug products with desired physical and chemical stability.
authors.affiliation: Department of Pharmaceutics and Drug Delivery, School of Pharmacy, The University of Mississippi, University, MS, USA.
authors.forename: Xin
authors.initials: X
authors.lastname: Feng
authors.affiliation: Department of Pharmaceutics and Drug Delivery, School of Pharmacy, The University of Mississippi, University, MS, USA.
authors.forename: Anh
authors.initials: A
authors.lastname: Vo
authors.affiliation: Department of Pharmaceutics and Drug Delivery, School of Pharmacy, The University of Mississippi, University, MS, USA.
authors.forename: Hemlata
authors.initials: H
authors.lastname: Patil
authors.affiliation: Department of Pharmaceutics and Drug Delivery, School of Pharmacy, The University of Mississippi, University, MS, USA.
authors.forename: Roshan V
authors.initials: RV
authors.lastname: Tiwari
authors.affiliation: Department of Pharmaceutics and Drug Delivery, School of Pharmacy, The University of Mississippi, University, MS, USA.
authors.forename: Abdullah S
authors.initials: AS
authors.lastname: Alshetaili
authors.affiliation: Department of Pharmaceutics and Drug Delivery, School of Pharmacy, The University of Mississippi, University, MS, USA.
authors.forename: Manjeet B
authors.initials: MB
authors.lastname: Pimparade
authors.affiliation: Department of Pharmaceutics and Drug Delivery, School of Pharmacy, The University of Mississippi, University, MS, USA.|Pii Center for Pharmaceutical Technology, The University of Mississippi, University, MS, USA.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Repka
mesh_terms: D065966:Absorption, Physicochemical; D002482:Cellulose / Q000031:analogs & derivatives / Q000737:chemistry; D004339:Drug Compounding; D011345:Fenofibrate / Q000737:chemistry*; D006358:Hot Temperature; D057927:Hydrophobic and Hydrophilic Interactions; D008970:Molecular Weight; D011092:Polyethylene Glycols / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013678:Technology, Pharmaceutical / Q000379:methods*; D014867:Water / Q000737:chemistry*; D017155:Wettability
chemical_list: D011108:Polymers; D014867:Water; D011092:Polyethylene Glycols; C013517:ethyl cellulose; D002482:Cellulose; C008079:hydroxypropylcellulose; D011345:Fenofibrate
keywords: amorphous; hot melt extrusion; moisture; polymer carrier; solid dispersion