title: In vitro release of ketoprofen from hydrophilic matrix tablets containing cellulose polymer mixtures.
abstract: The effect of cellulose ether polymer mixtures, containing both hydroxypropylcellulose (HPC) and hydroxypropylmethylcellulose (HPMC K15M or K100M), on ketoprofen (KTP) release from matrix tablets was investigated. In order to evaluate the compatibility between the matrix components, Raman spectroscopy, scanning electron microscopy (SEM), and X-ray powder diffraction (XRPD) experiments were performed. The results evidence the absence of significant intermolecular interactions that could eventually lead to an incompatibility between the drug and the different excipients. Formulations containing mixtures of polymers with both low and high viscosity grades were prepared by a direct compression method, by varying the polymer/polymer (w/w) ratio while keeping the drug amount incorporated in the solid dispersion constant (200 mg). The hardness values of different matrices were found within the range 113.8 to 154.9 N. HPLC analysis showed a drug content recovery between 99.3 and 102.1%, indicating that no KTP degradation occurred during the preparation process. All formulations attained a high hydration degree after the first hour, which is essential to allow the gel layer formation prior to tablet dissolution. Independent-model dissolution parameters such as t(10%) and t(50%) dissolution times, dissolution efficiency (DE), mean dissolution time (MDT), and area under curve (AUC) were calculated for all formulations. Zero-order, first-order, Higuchi, and Korsmeyer-Peppas kinetic models were employed to interpret the dissolution profiles: a predominantly Fickian diffusion release mechanism was obtained - with Korsmeyer-Peppas exponent values ranging from 0.216 to 0.555. The incorporation of HPC was thus found to play an essential role as a release modifier from HPMC containing tablets.
authors.affiliation: Unidade de I&D "Química Física Molecular", Faculdade de Ciências e Tecnologia da Universidade de Coimbra , Coimbra , Portugal.
authors.forename: M L
authors.initials: ML
authors.lastname: Vueba
authors.forename: L A E
authors.initials: LA
authors.lastname: Batista de Carvalho
authors.forename: F
authors.initials: F
authors.lastname: Veiga
authors.forename: J J
authors.initials: JJ
authors.lastname: Sousa
authors.forename: M E
authors.initials: ME
authors.lastname: Pina
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000032:analysis / Q000737:chemistry*; D002482:Cellulose / Q000031:analogs & derivatives / Q000737:chemistry*; D003692:Delayed-Action Preparations / Q000032:analysis / Q000737:chemistry; D004058:Diffusion; D004339:Drug Compounding; D004355:Drug Stability; D005079:Excipients / Q000737:chemistry*; D006244:Hardness; D057927:Hydrophobic and Hydrophilic Interactions; D065347:Hypromellose Derivatives; D007660:Ketoprofen / Q000032:analysis / Q000737:chemistry*; D007700:Kinetics; D008747:Methylcellulose / Q000031:analogs & derivatives / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D011108:Polymers / Q000737:chemistry*; D016062:Porosity; D033362:Powder Diffraction; D012995:Solubility; D013059:Spectrum Analysis, Raman; D013607:Tablets; D013718:Tensile Strength; D014783:Viscosity
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D003692:Delayed-Action Preparations; D005079:Excipients; D011108:Polymers; D013607:Tablets; D065347:Hypromellose Derivatives; D002482:Cellulose; D008747:Methylcellulose; D007660:Ketoprofen; C008079:hydroxypropylcellulose