perlite and titanium-dioxide

In this study, the photocatalytic decolorization of remazol red dye (RR) was evaluated using TiO

Topics: Aluminum Oxide; Catalysis; Research Design; Silicon Dioxide; Titanium

Photocatalytic degradation of an antibiotic, sulfamethoxazole (SMX), in aqueous solution using a novel floating TiO2-expanded perlite photocatalyst (EP-TiO2-773) and radiation from the near UV spectral range was studied. The process is important considering that SMX is known to be a widespread and highly persistent pollutant of water resources. SMX degradation was described using a pseudo-first-order kinetic equation according to the Langmuir-Hinshelwood model. The products of the SMX photocatalytic degradation were identified. The effect of pH on the kinetics and mechanism of SMX photocatalytic degradation was explained.

Topics: Aluminum Oxide; Anti-Bacterial Agents; Catalysis; Hydrogen-Ion Concentration; Kinetics; Photochemistry; Silicon Dioxide; Solutions; Spectrophotometry, Ultraviolet; Sulfamethoxazole; Titanium; Water

In this study, we introduce a porous composite material, termed "Ecopore", and describe in vitro investigation of the material and its modification with fibronectin. The material is a sintered compound of rutile TiO2 and the volcanic silicate perlite with a macrostructure of interconnecting pores. It is both inexpensive and easy to manufacture. We first investigated Ecopore for corrosion and leaching of elements in physiological saline. The corrosion supernatants did not contain critical concentrations of toxic trace elements. In an in vitro model, human primary osteoblasts (HOB) were cultured directly on Ecopore. HOB grew on the composite as well as on samples of its single constituents, TiO2 and perlite glass, and remained vital, but cellular spreading was less than on tissue culture plastic. The pro-inflammatory cytokines IL-1 and TNF-alpha were below detection limits in HOB culture supernatants, whereas IL-6 was detectable on a low level. To enhance cellular attachment and growth, the surface of the composite was modified by etching, functionalization with aminosilane and coupling of fibronectin. This modification greatly enhanced the spreading of HOB, indicated by vital staining and Sodium 3'-[1-(phenylaminocarbonyl)-3,4-tetrazolium]-bis (4-methoxy-6-nitro) benzene sulfonic acid hydrate (XTT) metabolism assays. HOB grew on the entire visible surface of porous fibronectin-modified composite, expressing alkaline phosphatase, a mature osteoblast marker. We conclude that Ecopore is non-toxic and sustains HOB growth, cellular spreading being improvable by coating with fibronectin. The composite may be usable in the field of bone substitution.

Topics: Alkaline Phosphatase; Aluminum Oxide; Biocompatible Materials; Bone and Bones; Bone Substitutes; Cell Culture Techniques; Cell Survival; Ceramics; Cytokines; Fibronectins; Humans; Indicators and Reagents; Inflammation; Interleukin-1; Microscopy, Electron, Scanning; Microscopy, Fluorescence; Osteoblasts; Silicates; Silicon Dioxide; Sodium Chloride; Surface Properties; Tetrazolium Salts; Titanium; Tumor Necrosis Factor-alpha