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In the current study, kappa carrageenan (κ-carr) and gelatin (gel) based hemostatic sponges were fabricated for dental applications. The K-carr and gel based dental sponges were characterized by attenuated total reflection-Fourier transform infrared spectroscopy. The morphological properties of the dental sponges were observed by Scanning Electron Microscope analysis. Thermal properties of sponges were evaluated by Thermogravimetric Analysis. The swelling and hydrolytic degradation percentages of the dental sponges were investigated in pH 6.8 to mimic oral saliva. The mechanical properties of the dental sponges were determined and were found to be higher in comparison with the commercial sponge. The sponges reached approximately 95% blood absorption at the end of 45 min. κ-carr and gel based dental sponges did not show cytotoxic effects on the L929 fibroblast cell line in thiazolyl blue tetrazolium bromide cell viability assay. All results suggested that the developed κ-carr and gel based dental sponges demonstrate great potential for dental applications for the future health care materials.

The aim of this research was to investigate the potential of ampicillin-loaded hydrogels based on polyvinyl alcohol (PVA), hyaluronic acid (HA) and kappa-carrageenan (K-Carr) as an antibiotic-releasing wound dressing. Firstly, the novel polymers (HA-g-K-Carr) were synthesized by grafting of HA onto K-Carr using 4-dimethylaminopyridine/1-(3-dimethylaminopyl)-3-ethyl-carbodiimide hydrochloride as catalyst system via esterification reaction. The characterization of the polymer structure was performed by Fourier transform infrared spectrum (FTIR), proton nuclear magnetic resonance and thermogravimetric analysis. Secondly, PVA/(HA-g-K-Carr) hydrogel with/without loading of ampicillin molecules was formed via freeze–thawing method since PVA/K-Carr and PVA/HA hydrogels were also fabricated as control groups. The hydrogels were subjected to characterizations with FTIR and X-ray diffractometer. PVA/(HA-g-K-Carr) hydrogel demonstrated the highest swelling amount and highest ampicillin release amount reaching an equilibrium value after 480 min rather than the other hydrogels. Also, PVA/(HA-g-K-Carr) hydrogel exhibited inhibition zone against Escherichia coliand Staphylococcus aureusand no cytotoxic effect for L929 cells. All the results showed that PVA/(HA-g-K-Carr) hydrogels are good candidates for wound dressing applications.

Graphene-Tin Oxide (G-SnO2) nanocomposites in different morphology were synthesized using tin (II) chloride (SnCl2) and graphene Oxide (GO) via hydrothermal process in the presence of hydrazine and ammonia by adding surfactant for 12 hours in a teflon autoclave at 100oC reaction temperature. Poly (vinyl prolidon) (PVP) and poly (ethylene glycol) (PEG) were used as nonionic surfactants while hexadecyl trimethyl ammonium bromide (CTAB) and sodium dodecyl sulfonate (SDS) were utilized as cationic and anionic surfactants, respectively. The synthesized nanocomposites were characterized by XRD, FESEM, C-TEM and FT-IR. The gas sensing properties of the obtained samples to the vapors of various Volatile Organic Compounds (VOC), such as Ethanol, Methanol, Chloroform, Toluene and Acetone were also investigated at room temperature. The prepared G-SnO2 nanocomposites exhibited high detection performances for ethanol, chloroform and methanol. The nanocomposites could be used as sensor material for VOC gases.

In this study, copper oxide (CuO) nanostructures were successfully prepared by adding EG (ethylene glycol) and PEG (4000, 8000) (polyethylene glycol) via an in-situ chemical precipitation method. EG and PEG (4000, 8000) were effective for changing the particular size of CuO and we examined the effects of drying type such as freeze drying, muffle and horizontal furnace on the size of CuO nanostructure. The structure, morphology and elemental analysis of CuO nanostructure were analyzed by field-emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDS). Also, the CuO nanostructures showed excellent electrical conductivity by the changing of PEG’s molecular weight and drying processes.

In this work, firstly we described the effect of freeze drying on modification of raw diatomite. And then, modified diatomite-leaf-like copper oxide (CuO) nanosheet composite was successfully prepared by surfactant-free in-situ chemical precipitation method. The structure, morphology and elemental analysis of CuO nanosheets and its composite were analyzed by field-emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), fourier transform infrared (FTIR) spectroscopy and energy dispersive X-ray spectroscopy (EDAX). Dimensions of leaf-like CuO nanosheets were approximately determined as 160 nm in width, 320 nm in length and 20 nm in thickness. According to the EDAX spectrum, leaf-like CuO nanosheets composed of Cu and O atoms without any impurity and also uniformly covered the entire surface of modified diatomite.