Reciprocal powered time model for release kinetic analysis of ibuprofen solid dispersions in oleaster powder, microcrystalline cellulose and crospovidone.

Purpose: A physically sound derivation for reciprocal power time (RPT) model for kinetic of drug release is given. In order to enhance ibuprofen dissolution, its solid dispersions (SDs) prepared by cogrinding technique using crospovidone (CP), microcrystalline cellulose (MC) and oleaster powder (OP) as a novel carrier and the model applied to the drug release data.

Methods: The drug cogrounds with the carriers were prepared and subjected to the dissolution studies. For elucidation of observed in vitro differences, FT-IR spectroscopy, X-ray diffraction patterns, DSC thermograms and laser particle size measurement were conducted.

Results: All drug release data fitted very well to newly derived RPT model. The efficiency of the carriers for dissolution enhancement was in the order of: CP>OP>MC. The corresponding release kinetic parameter derived from the model, t50% (time required for 50% dissolution) for the carrier to drug ratio 2:1 were 2.7, 10.2 and 12.6 min, respectively. The efficiency of novel carrier, OP, was between CP and MC. FT-IR showed no interaction between the carriers and drug. The DSC thermograms and X-ray diffraction patterns revealed a slight reduced crystallinty in the SDs. Also grinding reduced mean particle size of drug from 150.7 to 44.4 microm.

Conclusions: An improved derivation for RPT model was provided which the parameter of the model, t50%, unlike to previous derivations was related to the most important property of the drug i.e. its solubility. The model described very well drug release kinetics from the solid dispersions. Cogrinding was an effective technique in enhancing dissolution rate of ibuprofen. Elaeagnus angostifolia fruit powder was suggested as a novel potential hydrophilic carrier in preparing solid dispersion of ibuprofen.