title: Dissolution-modulating mechanism of pH modifiers in solid dispersion containing weakly acidic or basic drugs with poor water solubility.
abstract: BACKGROUND
  Although the solid dispersion method has been known to increase the dissolution rate of poorly water-soluble drugs by dispersing them in hydrophilic carriers, one obstacle of the solid dispersion method is its limited solubilization capacity, especially for pH-dependent soluble drugs.
  
  
  METHODS
  pH-modified solid dispersion, in which pH modifiers are incorporated, may be a useful method for increasing the dissolution rate of weakly acidic or basic drugs. Sufficient research, including the most recent reports, was undertaken in this review.
  
  
  RESULTS
  How could the inclusion of the pH the pH modifiers in the solid dispersion system change drug structural behaviors, molecular interactions, microenvironmental pH, and/or release rate of pH modifiers, relating with the enhanced dissolution of weakly acidic or weakly basic drugs with poor water solubility? These questions have been investigated to determine the dissolution-modulating mechanism of pH modifiers in solid dispersion containing weakly acidic or basic drugs.
  
  
  CONCLUSIONS
  It is believed that step-by-step mechanistic approaches could provide the ultimate solution for solubilizing several poorly water-soluble drugs with pH-dependent solubility from a solid dispersion system, as well as provide ideas for developing future dosage systems.
authors.affiliation: Kangwon National University, College of Pharmacy, Bioavailability Control Laboratory, Chuncheon, Republic of Korea.
authors.forename: Phuong Ha-Lien
authors.initials: PH
authors.lastname: Tran
authors.forename: Thao Truong-Dinh
authors.initials: TT
authors.lastname: Tran
authors.forename: Kyoung-Ho
authors.initials: KH
authors.lastname: Lee
authors.forename: Dong-Jin
authors.initials: DJ
authors.lastname: Kim
authors.forename: Beom-Jin
authors.initials: BJ
authors.lastname: Lee
mesh_terms: D003692:Delayed-Action Preparations / Q000737:chemistry*; D005079:Excipients / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D004364:Pharmaceutical Preparations / Q000008:administration & dosage / Q000737:chemistry*; D012995:Solubility
chemical_list: D003692:Delayed-Action Preparations; D005079:Excipients; D004364:Pharmaceutical Preparations