Correlation and in vitro studies on radioactive and nonradioactive albendazole-ß-cyclodextrin complex tablets

The work aims to confirm the complexation of albendazole (ABZ) by β-cyclodextrin (β-CD), and to compare them with pure ABZ tablets using radioactive and nonradioactive dissolution studies. The complex tablets were prepared by kneading a binary mixture of ABZ and β-CD and a direct compression method. Nuclear magnetic resonance (NMR) spectroscopy, scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy were examined to prove the formation of complexes in the final products. The radiolabelled tablets were labelled with 99mTc-DTPA. Dissolution studies were performed with radiolabelled and nonradiolabelled tablets in two dissolution media (pH 1.2 and pH 7.4). The tablets were added to an acidic solution (pH = 1.2) to quantify the concentration of the drug inside the β-CD cavity. The other medium (pH = 7.4) was used to prove the existence of non-complexed drug in each powder, as the drug's solubility increases with pH. It was observed that complexation occurred in all tablets, and β-cyclodextrin (β-CD) could increase the aqueous solubility. Further, a correlation was shown between dissolution results for radiolabelled and nonradiolabelled tablets. This study shows that the characterization studies were a good indicator for the ABZ: β-CD complex. According to the phase solubility studies, the solubility of ABZ increased when the amount of β-CD increased, and drug release from tablets in pH 7.4 and pH 1.2 media was dramatically improved by the addition of β-CD compared with the pure ABZ tablet.