Role of Cellulose Ether Polymers on Ibuprofen Release from Matrix Tablets

Abstract

Cellulose derivatives are the most frequently used polymers in formulations of pharmaceutical products for controlled drug delivery. The main aim of the present work was to evaluate the effect of different cellulose substitutions on the release rate of ibuprofen (IBP) from hydrophilic matrix tablets. Thus, the release mechanism of IBP with methylcellulose (MC25), hydroxypropylcellulose (HPC), and hydroxypropylmethylcellulose (HPMC K15M or K100M) was studied. In addition, the influence of the diluents lactose monohydrate (LAC) and beta-cyclodextrin (beta-CD) was evaluated. Distinct test formulations were prepared containing: 57.14% of IBP, 20.00% of polymer, 20.29% of diluent, 1.71% of talc lubricants, and 0.86% of magnesium stearate as lubricants. Although non-negligible drug-excipient interactions were detected from DSC studies, these were found not to constitute an incompatibility effect. Tablets were examined for their drug content, weight uniformity, hardness, thickness, tensile strength, friability, porosity, swelling, and dissolution performance. Polymers MC25 and HPC were found to be unsuitable for the preparation of this kind of solid dosage form, while HPMC K15M and K100M showed to be advantageous. Dissolution parameters such as the area under the dissolution curve (AUC), the dissolution efficiency (DE(20 h)), dissolution time (t 50%), and mean dissolution time (MDT) were calculated for all the formulations, and the highest MDT values were obtained with HPMC indicating that a higher value of MDT signifies a higher drug retarding ability of the polymer and vice-versa. The analysis of the drug release data was performed in the light of distinct kinetic mathematical models-Kosmeyer-Peppas, Higuchi, zero-, and first-order. The release process was also found to be slightly influenced by the kind of diluent used.

In vitro evaluation of sustained released matrix tablets containing ibuprofen: a model poorly water-soluble drug

“…Fickian diffusional release shows a rapid initial release, followed by a decrease in release owing to a chemical potential gradient (Bernard et al, 2004;Harris et al, 2006;Singh et al, 2012). These findings are in agreement with previous reports that have shown that poorly soluble drugs are released mainly by attrition mechanisms from hydrophilic and swellable polymeric matrices (Vueba et al, 2005). Table IV shows the values of r 2 and the rate constants obtained from the different kinetic models for the formulations investigated in this study.…”

New sustained release of Zidovudine Matrix tablets − cytotoxicity toward Caco-2 cells

“…This confirms that the drug:polymer ratio is an important factor affecting the drug release rates from HPMC matrices [64][65][66] . The gel layer that is formed delays further water uptake and the release of the dissolved drug.…”

Effects of Thermal Curing Conditions on Drug Release from Polyvinyl Acetate–Polyvinyl Pyrrolidone Matrices

“…Water insoluble filler excipients, such as DCP, tend to slow down drug release from HPMC matrices by getting entrapped within the matrix structure increasing the tortuosity of the matrix (32). Figure 6 shows the drug release from freshly prepared PVAc-PVP tablets prepared with different excipients.…”