Preparation and characterization of ketoprofen-layered double hydroxide compounds

Organo-mineral nanohibrid materials in which the organic moiety is intercalated inside the inorganic lamella were prepared by an ion exchange method. Ketoprofen (KET) anions were used as guest molecules, while ZnAl and MgAl layered double hydroxides (ZnAlLDH and MgAlLDH) were used as inorganic hosts. The intercalated compounds were examined by X-ray diffraction (XRD), FTIR spectroscopy, thermo gravimetric and scanning electron microscopy analysis techniques. The XRD patterns of the samples were found to be typical to those of well crystallized solids with the hydrotalcite structure. The basal spacing of the ZnAlLDH with nitrate as intergallery anion expanded from 8.74 angstrom to 22.36 angstrom upon drug intercalation. In the case of MgAlLDH the basal spacing expanded from 8.50 angstrom to 22.54 angstrom. The FTIR spectroscopy results prove the presence of the organic compound in the network structure of the synthesized hydrotalcites. The thermal stability of the intercalated KET was enhanced compared with the pure drug before intercalation. Elemental and chemical analysis of the intercalated compounds showed a good intercalation percentage, i.e. 45% for ZnAlLDH_KET and 50% for MgAlLDH_KET respectively (by weight).