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Kinetic Modelling of Drug Release from Pentoxifylline Matrix Tablets based on Hydrophilic, Lipophilic and Inert Polymers

Abstract

Pentoxifylline is a xanthine derivative used in the treatment of peripheral vascular disease, which because of its pharmacokinetic and pharmacologic profile is an ideal candidate for the development of extended release formulations. The aim of this study is to present a kinetic analysis of the pentoxifylline release from different extended release tablets formulations, using mechanistic and empirical kinetic models. A number of 28 formulations were prepared and analysed; the analysed formulations differed in the nature of the matrix forming polymers (hydrophilic, lipophilic, inert) and in their concentrations. Measurements were conducted in comparison with the reference product Trental 400 mg (Aventis Pharma). The conditions for the dissolution study were according to official regulations of USP 36: apparatus no. 2, dissolution medium water, volume of dissolution medium is 1,000 mL, rotation speed is 50 rpm, spectrophotometric assay at 274 nm. Six mathematical models, five mechanistic (0 orders, 1st-order release, Higuchi, Hopfenberg, Hixson-Crowell) and one empirical (Peppas), were fitted to pentoxifylline dissolution profile from each pharmaceutical formulation. The representative model describing the kinetics of pentoxifylline release was the 1st-order release, and its characteristic parameters were calculated and analysed.

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Famous hungarian chemists and pharmacists – modern chemistry founders. Part I. 1.2. Lajos Winkler

.Leito - Micro-Winkler titration method for dissolved oxygen concentration measurement . Analytica Chimica Acta, 2009, 648: 167-173. 16. Hodgson E.: Oxygen, that thing we all need to breathe. .. Monitoring, Oxygen, 2016, May 27. 17. Ulloa O., D.E. Canfield, E.F. DeLong, R.M.Letelier, F.J.Stewart - Microbial oceanography of anoxic oxygen minimum zones . PNAS, 2012,109(40):15996/16003. 18. Shriwastav A., Sudarsan G., Bose P., Tare V. - A modified Winkler,,s method for determination of dissolved oxygen concentration in water: Dependence of method accuracy on

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