PREPARATION AND EVALUATION OF NAPROXEN ADSORBATE AS AN ATTEMPT TO IMPROVE DRUG DISSOLUTION CHARACTERISTICS

Naproxen is a nonsteroidal anti-inflammatory drug which shows variable absorption and bioavailability due to its poor solubility. In this study we aimed to improve the dissolution rate of the drug by solvent deposition onto certain adsorbents including porous silica, Avicel and Bentonite. Physical mixtures of naproxen with the investigated adsorbents were also prepared. The molecular behavior of naproxen in the investigated systems were studied using infrared absorption spectra, differential scanning calorimetry and X-ray diffraction analysis. The dissolution rate of the drug was also investigated. The obtained results indicated that naproxen was transformed to the amorphous state in case of mixtures loaded with porous silica. This transformation resulted in a significant enhancement of the dissolution rates of the drug. In addition, it was noticed that, the drug: adsorbents weight ratio of the prepared mixtures influenced the drug dissolution rate enhancement. Accordingly, it can be concluded that, by increasing the weight ratio of the used adsorbent in the mixture, the larger the enhancement in the dissolution rate of naproxen will be obtained.