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The aim of this study was to investigate the effect of hydroxypropyl-β-cyclodextrin (HPβCD) on the solubility and dissolution rate of Cefdinir (CEF). The methods that were employed to prepare CEF–HPβCD complexes were Kneading (KN), Co-evaporation (CE), Spray drying (SD) and a novel approach of Microwave irradiation (MWI). The formation of inclusion complexes with HPβCD in the solid state, were characterized by Differential Scanning Calorimetry (DSC), Fourier Transformation Infrared spectroscopy (FTIR), Proton Nuclear Magnetic Resonance Spectroscopy (NMR), X Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) studies, and comparative studies on the in vitro dissolution of CEF were carried out. Phase solubility profile with HPβCD was classified as AL type, indicating the formation of 1:1 stoichiometric inclusion complexes. Characterization of binary systems by DSC, FTIR, NMR, XRD and SEM indicated that SD and MWI method resulted in formation of true complexes. Binary systems showed significant increase in dissolution rate as compared to plain drug. Amongst the various binary systems, MWI products were prepared in least time with better yield and highest dissolution rate.

The inclusion behaviour of β-cyclodextrin (βCD) was studied toward Cefdinir (CEF) in order to enhance the solubility and dissolution rate, following cyclodextrin complexation. Drug cyclodextrin solid systems were prepared by conventional methods of kneading (KN), co-evaporation (CE), spray drying (SD) and with a novel approach of microwave irradiation (MWI). The formation of inclusion complexes with βCD in the solid state, were confirmed by Differential scanning calorimetry (DSC), Fourier Transform Infrared spectroscopy (FTIR) and Scanning Electron Microscopy (SEM) studies, and comparative studies on the in vitro dissolution of CEF were carried out. Characterization of binary system by DSC, FTIR and SEM indicated that SD and MWI method resulted in formation of true complexes. Binary systems showed significant increase in dissolution rate as compared to plain drug. Amongst the binary systems MWI products were prepared in least time with better yield and highest dissolution rate.

In this work, we illustrate the usefulness of cyclodextrins, namely, methyl-β-cyclodextrin (MβCD), an amorphous, methylated derivative of the natural β-cyclodextrin, as a tool to form an inclusion complex with Valsartan (VAL), a poorly water soluble drug. The phase solubility study showed AL type of curve with slope less than one indicating the formation of complexes in 1:1 molar ratio of drug and CD. The stability constant was found to be 538.14 ± 5.4 Mole−1. Solid binary systems between VAL and MβCD were prepared experimentally in a stoichiometry 1:1 by different techniques (physical mixing, kneading, co-evaporation). Afterward these products were characterized by Fourier transform infrared spectroscopy (FTIR), Differential scanning calorimetry (DSC), Scanning electron microscopy (SEM) and 1H Nuclear magnetic resonance study (1H NMR). The results obtained suggested that co-evaporation methods yield a higher degree of amorphous entities suggesting the formation of inclusion complex between VAL and MβCD. The dissolution of VAL from the binary systems was studied to select the most appropriate system for the formulation development. It was concluded that the preparation technique played an important role in the dissolution behavior of the drug and the inclusion complex between VAL and MβCD obtained by co-evaporation method allowed better performance.

The aim of the present investigation was to develop a modified release effervescent floating drug delivery system of famotidine for 12 h dosage regimen to improve its bioavailability. Effervescent floating tablets were prepared by direct compression method taking into account its advantages over wet granulation by using directly compressible excipients like Carbopol® 71G and Cellactose® 80. The incorporation of sodium bicarbonate aided in the buoyancy with effervescent approach. The prepared tablets were evaluated for floating lag time (FLT), total floating time (TFT), in vitro drug release along with general parameters. 23 factorial design was used for optimization. The tablets showed desired release of more than 98 % over the period of 12 h which may increase bioavailability of selected candidate. The release of famotidine was found to be influenced by the polymer concentration. Optimized formulation showed acceptable stability over three months at 40 ºC and 75 % RH., Colegio de Farmacéuticos de la Provincia de Buenos Aires