title: Understanding the impact of media viscosity on dissolution of a highly water soluble drug within a USP 2 mini vessel dissolution apparatus using an optical planar induced fluorescence (PLIF) method.
abstract: In this study, planar induced fluorescence (PLIF) was used for the first time to evaluate variability in drug dissolution data using Rhodamine-6G doped tablets within small volume USP 2 apparatus. The results were compared with tablets contained theophylline (THE) drug for conventional dissolution analysis. The impact of hydrodynamics, sampling point, dissolution media viscosity and pH were investigated to note effects on release of these two actives from the hydrophilic matrix tablets. As expected mixing performance was poor with complex and reduced velocities at the bottom of the vessel close to the tablet surface; this mixing became even worse as the viscosity of the fluid increased. The sampling point for dissolution can affect the results due to in-homogenous mixing within the vessel; this effect is exacerbated with higher viscosity dissolution fluids. The dissolution profiles of RH-6G measured via PLIF and THE measured using UV analysis were not statistically different demonstrating that RH-6G is an appropriate probe to mimic the release profile of a highly soluble drug. A linear correlation was accomplished between the release data of the drug and the dye (R(2)>0.9). The dissolution profile of the dye, obtained with the analysis of the PLIF images, can be used in order to evaluate how the viscosity and the mixing performance of USP 2 mini vessel affect the interpretation of the dissolution data of the targeted drug.
authors.affiliation: School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom.
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Stamatopoulos
authors.affiliation: Pharmacy and Therapeutics Section, School of Clinical and Experimental Medicine, College of Medical and Dental Sciences (CMDS), Medical School Building, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom.
authors.forename: Hannah K
authors.initials: HK
authors.lastname: Batchelor
authors.affiliation: School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom.
authors.forename: Federico
authors.initials: F
authors.lastname: Alberini
authors.affiliation: School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom.
authors.forename: John
authors.initials: J
authors.lastname: Ramsay
authors.affiliation: School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom. Electronic address: KXS231@student.bham.ac.uk.
authors.forename: Mark J H
authors.initials: MJH
authors.lastname: Simmons
mesh_terms: D002266:Carboxymethylcellulose Sodium / Q000737:chemistry; D002626:Chemistry, Pharmaceutical / Q000295:instrumentation*; D065546:Drug Liberation; D057446:Hydrodynamics; D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D012235:Rhodamines / Q000737:chemistry; D012995:Solubility; D013607:Tablets / Q000737:chemistry*; D013806:Theophylline / Q000737:chemistry; D014783:Viscosity
chemical_list: D012235:Rhodamines; D013607:Tablets; C026188:rhodamine 6G; D013806:Theophylline; D002266:Carboxymethylcellulose Sodium
keywords: Dissolution test; Planar laser-induced fluorescence; Rhodamine-6G; Texture analysis; Theophylline; USP 2 mini paddle