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ABSTRACT The current study focuses on the alteration of properties of the gelatin hydrogels using polysaccharides (e.g., maltodextrin, dextran, and sodium carboxymethyl cellulose) for probable use in vaginal delivery of antimicrobials. The hydrogels were prepared by varying the proportions of gelatin and polysaccharides and were characterized by microscopy, mechanical testing, and impedance spectroscopy. Metronidazole (MZ), drug of choice for the treatment of bacterial vaginosis, was incorporated within the hydrogels. In vitro release studies of MZ from the hydrogels was studied in-depth using modified Franz's diffusion cell. Antimicrobial efficiency of the MZ-loaded hydrogels was tested against E. coli and B. subtilis. The results suggested that the incorporation of polysaccharides resulted in the phase-separated hydrogels. The properties of the hydrogels was found be suitable for vaginal delivery. The drug release and antimicrobial efficiency from the hydrogels suggested that the developed hydrogels may be used for the delivery of antimicrobials in the vaginal lumen. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40445. [ABSTRACT FROM AUTHOR]

A series of lead-free perovskite solid solutions of (1 − x) Na0.5 Bi0.5 TiO3( NBT)- x BaSnO3( BSN), for 0.0 ≤ x ≤ 0.15 have been synthesized using a high-temperature solid-state reaction route. The phase transition behaviors are studied using dielectric and Raman spectroscopic techniques. The ferroelectric to relaxor phase transition temperature ( TFR) and the temperature corresponding to maximum dielectric permittivity ( Tm) are estimated from the temperature-dependent dielectric data. Dielectric studies show diffuse phase transition around ~335°C in pure NBT and this transition temperature decreases with increase in x. The disappearance of x-dependence of A1 mode frequency at ~134 cm−1 for x ≥ 0.1 is consistent with rhombohedral-orthorhombic transition. In situ temperature dependence Raman spectroscopic studies show disappearance and discontinuous changes in the phonon mode frequencies across rhombohedral ( x < 0.1)/orthorhombic ( x ≥ 0.1) to tetragonal transition. [ABSTRACT FROM AUTHOR]