Improvement of water solubility and in vitro dissolution rate of gliclazide by complexation with β-cyclodextrin1

Inclusion complexes of gliclazide with β-cyclodextrin were prepared using different two methods: neutralization and recrysstalization. Host–guest interactions were studied in the solid state by X-ray diffractometry and infrared spectroscopy. The stability constant between gliclazide and β-cyclodextrin was calculated from the phase solubility diagram. It was found that the neutralization technique and a solid complex of gliclazide with β-cyclodextrin in a molar ratio of 1.5:1 could be used to prepare the amorphous state of drug inclusion complexes. The dissolution rates of gliclazide from the inclusion complex made by neutralization was much faster than the pure drug, physical mixture of drug and cyclodextrin, recyristalization system and also comparable to the data reported in literature. Results of this report indicate that β-cyclodextrin could be useful for the solid gliclazide formulations as it may results in a more rapid and uniform release of the drug.