Our data support the hypothesis that the biological activity of quartz dust is not due to crystallinity but to crystal fragmentation, when conchoidal fractures are formed. Fracturing imparted a higher heterogeneity of silanol acidic sites and radical species at the quartz surface. When fractured, synthetic quartz (μ-Qz-syn-f) attained particle morphology and size close to the mineral quartz dust (Qz-f, positive control) and similarly induced cellular toxicity and membranolysis. Independently from size as-grown quartz crystals with regular intact faces did not elicit cellular toxicity and lysosomal stress on RAW 264.7 macrophages, and were non-membranolytic on liposome and red blood cells. Quartz crystals were grown in the submicron (n-Qz-syn) or micron (μ-Qz-syn) range by modulating the synthetic procedure. Endpoints of cellular stress were evaluated on RAW 264.7 murine macrophages by High Content Analysis after ascertaining cellular uptake by bio-TEM imaging of quartz-exposed cells. Membranolysis was assessed on biological and artificial membranes. The key physico-chemical features relevant to particle toxicity - particle size distribution, micromorphology, crystallinity, surface charge, cell-free oxidative potential - were evaluated. Quartz crystals were grown and compared with a fractured specimen obtained by grinding the largest synthetic crystals and a mineral quartz (positive control). To clarify the role of crystallinity in quartz pathogenicity we have grown intact quartz crystals in respirable size. Quartz dusts used so far in particle toxicology have been obtained by grinding rocks containing natural quartz, a process which affects crystallinity and yields dusts with variable surface states. Crystallinity and various surface features are implied in toxicity. What imparts pathogenicity to any single quartz source is however still unclear. The price shown is per single drum (including VAT). For larger quantities please contact us to request a quote.Exposure to some - but not all - quartz particles is associated to silicosis, lung cancer and autoimmune diseases. The silica gel meets all the requirements of non-toxicity and the absence of contaminant DMF according to EC standards This large packaging is specially conceived to meet the demand for industrial and pharmaceutical supplies on large scale. Silica gel will remove moisture at temperatures as high as 65 C°, but it is best used at room temperature (20-35 C°) and high relative humidity (60‐90% RH) Silica gel’s interconnected pores form a vast surface area that will attract and hold water by adsorption and capillary condensation, enabling silica gel to adsorb about 40% of its weight in water vapor at 100% humidity. Many of the items stored by these institutions are prone to moisture damage due to their great age. Silica gel is also commonly used as a preservation tool in libraries and museums. It's possible to prevent system breakdowns due to the build up of moisture. Silica gel are used to absorb moisture in industrial installations, railway locomotives, air treatment plants, compressed air systems, etc. Its outer surfaces stay dry and it remains free-flowing, even when it is saturated with water. Silica gel is non-deliquescent, and its shape and size never change. Silica gel is the naturally occurring mineral silicon dioxide that has been purified and processed into a beaded or granular form, and is also non-corrosive and chemically inert. It is a highly activated adsorbent tasteless, odorless, non-toxic, non-corrosive, and chemically inert substance. During adsorption, there is no chemical reaction in the silica gel, and no byproducts are created. White silica gel, amorphous crystals, grain size 3-6 mm.
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