A New Photocatalyst Bismuth Oxo Citrate: Synthesis, Characterization, and Photocatalytic Performance.

  A new photocatalyst bismuth oxo citrate was synthesized by facile precipitation process with calcination at 200 °C. The photocatalyst was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, N2 sorptometry, and elemental analysis. Morphologically, it is composed of polyhedral particles with different, irregular shapes and sizes.

Bone Healing Following Different Types of Osteotomy: Scanning Electron Microscopy (SEM) and Three-Dimensional SEM Analyses.

The aim of the present study was to compare dynamics of the bone healing process after different types of osteotomies. In total, 24 Wistar rats were subjected to different types of osteotomy performed with standard steel bur, piezosurgery, contact, and non-contact Erbium:yttrium-aluminum-garnet (Er:YAG) laser ablation. The animals were randomly divided into four groups, to be euthanized immediately after the procedure, or at 1, 2, or 3 weeks after surgery.

Enamel alteration following tooth bleaching and remineralization.

The purpose of this study was to compare the effects of professional tooth whitening agents containing highly concentrated hydrogen peroxide (with and without laser activation), on the enamel surface; and the potential of four different toothpastes to remineralize any alterations. The study was performed on 50 human molars, divided in two groups: treated with Opalescence(®) Boost and Mirawhite(®) Laser Bleaching. Furthermore, each group was divided into five subgroups, a control one and 4 subgroups remineralized with: Mirasensitive(®) hap+, Mirawhite(®) Gelleѐ, GC Tooth Mousse™ and Mirafluor(®) C.

Development and optimization of ketoconazole oral strips by means of continuous hot-melt extrusion processing.

Objectives: The aim of this study was to develop mucoadhesive oral strips using hot-melt extrusion as a continuous manufacturing process.

Methods: Powder blends of ketoconazole, a water-insoluble drug - either hydroxypropyl methylcellulose (HPMC) or soluplus (SOL), sorbitol (SRB) and magnesium aluminometasilicate (MAS) were extruded to manufacture thin strips with 0.5-mm thickness.

Delivery of retinoic acid to LNCap human prostate cancer cells using solid lipid nanoparticles.

In this study retinoic acid (RTA) loaded solid lipid nanoparticles (SLNs) were optimized by tuning the process parameters (pressure/temperature) and using different lipids to develop nanodispersions with enhanced anticancer activity. The RTA-SLN dispersions were produced by high-pressure homogenization and characterized in terms of particle size, zeta potential, drug entrapment efficiency, stability, transmission electron microscopy (TEM), atomic force microscopy (AFM), X-ray diffraction (XRD) and in vitro drug release. Thermal and X-ray analysis showed the RTA to be in the amorphous state, whilst microscopic images revealed a spherical shape and uniform particle size distribution of the nanoparticles.

The incorporation of nanoparticles into conventional glass-ionomer dental restorative cements.

Conventional glass-ionomer cements (GICs) are popular restorative materials, but their use is limited by their relatively low mechanical strength. This paper reports an attempt to improve these materials by incorporation of 10 wt% of three different types of nanoparticles, aluminum oxide, zirconium oxide, and titanium dioxide, into two commercial GICs (ChemFil® Rock and EQUIA™ Fil). The results indicate that the nanoparticles readily dispersed into the cement matrix by hand mixing and reduced the porosity of set cements by filling the empty spaces between the glass particles.

SEM/EDX and confocal Raman microscopy as complementary tools for the characterization of pharmaceutical tablets.

The drug distribution on the surface of hot-melt extruded, pre-mixed hot-melt extruded and direct compressed tablet formulations was characterized by using scanning electron microscopy, energy dispersive X-ray spectroscopy (EDX) and confocal Raman spectroscopy. Formulations of paracetamol (PMOL) and Compritol(®) (C-888) were extruded using hot-melt extrusion at different processing temperatures and formulation compositions before being compressed into tablets. EDX and confocal Raman spectroscopy were employed to map the drug and excipient distribution, both qualitatively and quantitatively, on the surface of the tablets.

Prediction of polymorphic transformations of paracetamol in solid dispersions.

A novel approach employing variable-temperature X-ray powder diffraction (VTXRPD) was used to exploit its suitability as an off-line predictive tool to study the polymorphic transformations of paracetamol (PMOL) in melt-extruded hydrophilic polymer matrices. Physical mixtures (PMs) and extruded formulations of PMOL with either polyvinyl caprolactam graft copolymer (Soluplus®) or vinylpyrrolidone-vinyl acetate copolymer (Kollidon®) in the solid state were characterized by using differential scanning calorimetry, hot-stage microscopy, and scanning electron microscopy. The experimental findings from VTXRPD showed that the stable Form I (monoclinic) of PMOL transformed to the metastable polymorph Form II (orthorhombic) at temperatures varying from 112°C to 120°C, in both the PMs and extrudates suggesting an effect of both temperature and identity of the polymers.

Interfacial properties of three different bioactive dentine substitutes.

Three different bioactive materials suitable as dentine substitutes in tooth repair have been studied: glass-ionomer cement, particulate bioglass, and calcium-silicate cement. On 15 permanent human molars, Class V cavities were prepared and the bottom of each cavity was de-mineralized by an artificial caries gel. After the de-mineralization, the teeth were restored with: (1) Bioglass®45S5 and ChemFil® Superior; (2) Biodentine™ and ChemFil® Superior; and (3) ChemFil® Superior for a complete repair.

Remineralization of demineralized enamel by toothpastes: a scanning electron microscopy, energy dispersive X-ray analysis, and three-dimensional stereo-micrographic study.

Remineralization of hard dental tissues is thought to be a tool that could close the gap between prevention and surgical procedures in clinical dentistry. The purpose of this study was to examine the remineralizing potential of different toothpaste formulations: toothpastes containing bioactive glass, hydroxyapatite, or strontium acetate with fluoride, when applied to demineralized enamel. Results obtained by scanning electron microscopy (SEM) and SEM/energy dispersive X-ray analyses proved that the hydroxyapatite and bioactive glass-containing toothpastes were highly efficient in promoting enamel remineralization by formation of deposits and a protective layer on the surface of the demineralized enamel, whereas the toothpaste containing 8% strontium acetate and 1040 ppm fluoride as NaF had little, if any, remineralization potential.

A facile synthesis route of size tunable CdS quantum dots with high photoluminescence yield.

Water soluble CdS nanoparticles were synthesized by reacting CdCl2 with sodium thiosulphate solutions as sulphur precursor. The facile one-pot synthetic route produced tunable (2-10 nm) high quality QDs with narrow particle size distribution and enhanced quantum yields (QY).

The application of electrostatic dry powder deposition technology to coat drug-eluting stents.

Purpose: A novel methodology has been introduced to effectively coat intravascular stents with sirolimus-loaded polymeric microparticles.

Methods: Dry powders of the microparticulate formulation, consisting of non-erodible polymers, were produced by a supercritical, aerosol, solvent extraction system (ASES). A design of experiment (DOE) approach was conducted on the independent variables, such as organic/CO(2) phase volume ratio, polymer weight and stirring-rate, while regression analysis was utilized to interpret the influence of all operational parameters on the dependent variable of particle size.

Marginal adaptation and performance of bioactive dental restorative materials in deciduous and young permanent teeth.

Objective: The aim of this study was to investigate the adaptation of different types of restorations towards deciduous and young permanent teeth.

Material And Methods: Class V cavities were prepared in deciduous and young permanent teeth and filled with different materials (a conventional glass-ionomer, a resin-modified glass-ionomer, a poly-acid-modified composite resin and a conventional composite resin). Specimens were aged in artificial saliva for 1, 6, 12 and 18 months, then examined by SEM.

Interactions of aqueous Cu2+, Zn2+ and Pb2+ ions with crushed concrete fines.

The crushing of reclaimed concrete-based demolition waste to produce recycled aggregate gives rise to a large volume of cement-rich fine material for which market development would be beneficial. It was envisaged that this fine fraction may prove to be an effective sorbent for aqueous heavy metal species by virtue of its ion exchangeable phases and high pH. A batch sorption study confirmed that crushed concrete, in the particle size range 1-2 mm, successfully excluded Cu2+ (35 mg g(-1)), Zn2+ (33 mg g(-1)) and Pb2+ (37 mg g(-1)) from aqueous media.