In the present investigation, GO was prepared by exfoliation of graphite using modified Hummer's method and then reduced using hydrazine hydrate (reducing agent) to produce rGO. XRD, FESEM, Raman, FTIR spectrophotometer and TGA were used for characterization of GO and rGO. XRD images reveal crystalline structure for both GO and rGO. The d‐spacing is observed to be reduced for rGO as compared to that for GO because of removal of oxygen containing functional groups. Raman excitation peaks were obtained for two laser wavelengths 532 and 785 nm. Ratio of intensities of D and G bands (ID/IG) increase for rGO due to increase in order by reduction, implying restoration of the p‐conjugation. The bands are narrower for rGO.TGA thermograms show a higher overall loss of weight for GO in the temperature range 0–1000 °C under N2 flow. Intensity of FTIR peaks of oxide, hydroxyl and alkoxy groups decreases significantly on reduction. FESEM image shows more corrugated surface of rGO as compared to GO. It is expected that this investigation would be useful to develop GO/rGO based gas sensors to detect minute concentration of gases.

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Polymer nanocomposites exhibiting superparamagnetic behavior have been recognized as a promising tool to achieve targeted drug delivery using external magnetic field for treating complex diseases like cancers and tumors. The present investigation attempts to design a superparamagnetic nanocomposite which could desirably deliver ciprofloxacin drug by application of varying magnetic field. In order to achieve the proposed objectives, a polymer matrix of polyvinyl alcohol-g-polymethyl methacrylate was prepared by free radical polymerization and iron oxide particles were impregnated by in situ precipitation method. The prepared nanocomposites were characterized by techniques like FTIR, electron microscopy (SEM and TEM) and XRD and magnetization studies were performed to ensure superparamagnetic behavior. The antibiotic drug ciprofloxacin was loaded onto the magnetic nanocomposites and the influence of various factors such as percent loading, chemical composition of the nanocomposite, applied magnetic field, pH of the release medium were investigated on the release profiles of the drug. The chemical integrity of the drug and its antibacterial potential were also studied. The dynamics of the release process was also examined mechanistically.