title: Assessment of disintegrant efficacy with fractal dimensions from real-time MRI.
abstract: An efficient disintegrant is capable of breaking up a tablet in the smallest possible particles in the shortest time. Until now, comparative data on the efficacy of different disintegrants is based on dissolution studies or the disintegration time. Extending these approaches, this study introduces a method, which defines the evolution of fractal dimensions of tablets as surrogate parameter for the available surface area. Fractal dimensions are a measure for the tortuosity of a line, in this case the upper surface of a disintegrating tablet. High-resolution real-time MRI was used to record videos of disintegrating tablets. The acquired video images were processed to depict the upper surface of the tablets and a box-counting algorithm was used to estimate the fractal dimensions. The influence of six different disintegrants, of different relative tablet density, and increasing disintegrant concentration was investigated to evaluate the performance of the novel method. Changing relative densities hardly affect the progression of fractal dimensions, whereas an increase in disintegrant concentration causes increasing fractal dimensions during disintegration, which are also reached quicker. Different disintegrants display only minor differences in the maximal fractal dimension, yet the kinetic in which the maximum is reached allows a differentiation and classification of disintegrants.
authors.affiliation: Institute of Pharmaceutics and Biopharmaceutics, Heinrich-Heine-University, Universitaetsstasse 1, Duesseldorf 40225, Germany.
authors.forename: Julian
authors.initials: J
authors.lastname: Quodbach
authors.affiliation: Biomedizinische NMR Forschungs GmbH am Max-Planck-Institut für Biophysikalische Chemie, Am Fassberg 11, Goettingen 37070, Germany.
authors.forename: Amir
authors.initials: A
authors.lastname: Moussavi
authors.affiliation: Biomedizinische NMR Forschungs GmbH am Max-Planck-Institut für Biophysikalische Chemie, Am Fassberg 11, Goettingen 37070, Germany; Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Goettingen 37070, Germany.
authors.forename: Roland
authors.initials: R
authors.lastname: Tammer
authors.affiliation: Biomedizinische NMR Forschungs GmbH am Max-Planck-Institut für Biophysikalische Chemie, Am Fassberg 11, Goettingen 37070, Germany; Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Goettingen 37070, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Frahm
authors.affiliation: Institute of Pharmaceutics and Biopharmaceutics, Heinrich-Heine-University, Universitaetsstasse 1, Duesseldorf 40225, Germany. Electronic address: kleinebudde@hhu.de.
authors.forename: Peter
authors.initials: P
authors.lastname: Kleinebudde
mesh_terms: D002266:Carboxymethylcellulose Sodium / Q000737:chemistry; D002626:Chemistry, Pharmaceutical / Q000379:methods*; D005079:Excipients / Q000737:chemistry*; D017709:Fractals; D008279:Magnetic Resonance Imaging; D011205:Povidone / Q000737:chemistry; D012117:Resins, Synthetic / Q000737:chemistry; D012995:Solubility; D013213:Starch / Q000031:analogs & derivatives / Q000737:chemistry; D013607:Tablets / Q000737:chemistry*
chemical_list: D005079:Excipients; D012117:Resins, Synthetic; D013607:Tablets; D013213:Starch; C048390:sodium starch glycolate; C046797:amberlite; D011205:Povidone; D002266:Carboxymethylcellulose Sodium
keywords: Formulation; Polymers; Superdisintegrants; Tablet disintegration; Visualization