title: Preparation and characterization of celecoxib dispersions in soluplus(®): comparison of spray drying and conventional methods.
abstract: The present study deals with characterization of dispersions of a poorly water-soluble drug, celecoxib (CLX) in polyvinyl caprolactame-polyvinyl acetate-polyethylene glycol graft copolymer (Soluplus(®) (SOL)) prepared by different techniques. Dispersions of CLX in SOL at different ratios (2:1, 1:1, 1:2, 1:4 and 1:6) were prepared by spray drying, conventional solvent evaporation and melting methods. The solid states of samples were characterized using particle size measurements, optical and scanning electron microscopy, XRPD, DSC and FT-IR. The Gordon-Taylor equation was used to predict the Tg of samples and the possibility of interaction between CLX and SOL. The solubility and dissolution rate of all samples were determined. Stability of samples was studied at ambient conditions for a period of 12 months. DSC and XRPD analyses confirmed amorphous state of drug in samples. Surprisingly dispersions of CLX:SOL with the ratio of 2:1 and 1:1 showed slower dissolution rate than CLX while other samples showed higher dissolution rate. At 1:2 ratio the spray dried samples exhibited higher dissolution rate than corresponding samples prepared by other methods. However at higher SOL content (1:4 and 1:6), samples prepared by different methods showed similar dissolution profiles. The stability studies showed that there were no remarkable changes in the dissolution profiles and solid state of the drug after 12 months storage at ambient conditions. It was concluded that SOL was a proper carrier to enhance the dissolution rate of CLX. At high SOL ratios the method of preparation of dispersed samples had no effect on dissolution rate, whilst at low SOL content spray drying was more efficient method.
authors.affiliation: Department of Pharmaceutics, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Alireza
authors.initials: A
authors.lastname: Homayouni
authors.affiliation: Targeted Drug Delivery Research Center, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran. ; Department of Pharmaceutics, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Sadeghi
authors.affiliation: Chemistry and Drug Delivery Group, Medway School of Pharmacy, University of Kent, ME4 4TB, Kent, United Kingdom. ; Drug Applied Research Center and Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Nokhodchi
authors.affiliation: Department of Pharmaceutics, Faculty of Pharmacy and Novel Drug Delivery System Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Jaleh
authors.initials: J
authors.lastname: Varshosaz
authors.affiliation: Pharmaceutical Research Center, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran. ; Department of Pharmaceutics, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Hadi
authors.initials: H
authors.lastname: Afrasiabi Garekani
keywords: Celecoxib; Dissolution rate; Solid dispersion; Solid states; Soluplus®