The objective of the present study is to prepare and characterize cyclodextrin inclusion complexes of quercetin and rutin to improve their aqueous solubility and dissolution properties. Inclusion complexes of quercetin and rutin with beta-cyclodextrin (beta-CD) and hydroxyl propyl-beta-cyclodextrin (HP-beta-CD) were prepared by kneading and coevaporation methods. Characterization of inclusion complexes was done by phase solubility analysis and was supported by X-ray powder diffractometry (XRD), differential scanning calorimetry (DSC), and Fourier-transform infra red spectroscopy (FT-IR) analysis. Inclusion complexes exhibited higher rates of dissolution than the corresponding physical mixtures and pure drug. Higher dissolution rates were observed with HP-beta-CD kneaded complexes in comparison to the products with beta-CD.

Metal induced decrease of crystallization temperature of sol-gel derived titanium dioxide (TiO 2 ) thin films is reported. It is shown that the Au induced onset of crystallization occurs at a temperature of 250 C as compared to 400 C when it is deposited directly on the same substrate. The crystallization process is probed using X-ray diffraction and confirmed by Raman spectroscopy. The onset of crystallization is evidenced by the appearance of the diffraction peak from the (101) plane of anatase TiO 2 and the peak due to A 1g + B 1g Raman mode at 515 cm À1 . Polarized optical microscopy and Raman imaging indicated that the spatial spread of crystallization across the surface of the film increases with the increase in temperature. Unipolar resistive switching is demonstrated by fabricating an Au/TiO 2 /Au stack, which shows formation at 9 V, set voltage of 0.5 V and reset voltage of 3.3 V. The maximum set-reset resistance ratio achieved was 10 5 . The mechanism of resistive switching is established by a correlation with photoluminescence spectra which indicates the presence of defects that aid in the switching process.

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