Search results for "Polyphosphate"
showing 10 items of 95 documents
A bio-imitating approach to fabricate an artificial matrix for cartilage tissue engineering using magnesium-polyphosphate and hyaluronic acid
2016
Here we describe an artificial cartilage-like material based on a hyaluronic acid-Mg/Ca-polyphosphate paste (HA-aMg/Ca-polyP-p) that is fabricated from a water-soluble Na-salt of energy-rich inorganic polyphosphate (polyP) and soluble hyaluronic acid in the presence of water-insoluble CaCO3. The resulting material, after conversion of Na-polyP into the less soluble Mg/Ca-salt consisting of amorphous Mg/Ca-polyP microparticles, was found to mimic the physiological cartilage tissue and to bind Ca2+ ions present in the synovial fluid. After the Mg2+/Ca2+ exchange and water extrusion, the polyP becomes more stable, but is still susceptible to hydrolytic cleavage by the alkaline phosphatase (ALP…
The metabolic versatility of PAOs as an opportunity to obtain a highly P-enriched stream for further P-recovery
2015
The effects of two sequencing batch reactor operation strategies for phosphorus stream enrichment over the biological phosphorus removal performance have been studied. The objective of both strategies is of performing an extraction cycle in order to obtain a new stream highly enriched with phosphorus. In the 1st strategy the amount of influent volatile fatty acids (VFAs) is the same in each cycle; while in the 2nd strategy the influent VFAs concentration is increased during phosphorus extraction experiments. Despite the strong decrease of the stored poly-P inside the cells in both strategies after the recovery cycles, the ability of the systems to remove phosphorus was not affected. The P-r…
Inorganic Polyphosphate in Human Osteoblast-like Cells
1998
Significant amounts of inorganic polyphosphates and of polyphosphate-degrading exopolyphosphatase activity were detected in human mandibular-derived osteoblast-like cells. The amount of both soluble and insoluble long-chain polyphosphate in unstimulated osteoblast-like cells was higher than in human gingival cells, erythrocytes, peripheral blood mononuclear cells, and human blood plasma. The cellular content of polyphosphate in osteoblast-like cells strongly decreased after a combined treatment of the cells with the stimulators of osteoblast proliferation and differentiation, dexamethasone, beta-glycerophosphate, epidermal growth factor, and ascorbic acid. The amount of soluble long-chain p…
Biomimetic routes to micro/nanofabrication
2020
Abstract The discovery of inorganic polyphosphate (polyP), an evolutionarily ancient biopolymer, and of its function in energy storage/supply and induction of cell differentiation through specific gene expression (“morphogenetic activity”) has opened new opportunities in regenerative medicine, including therapy of bone, cartilage, and vascular diseases. Inspired by nature, various procedures have been developed for the preparation of amorphous nano and microparticles of polyP with different counterions, which mimic the physiological polyP found in blood platelets/acidocalcisomes, as well as for the preparation of morphogenetically active polyP coacervate complexes. This chapter summarizes t…
A physiologically active interpenetrating collagen network that supports growth and migration of epidermal keratinocytes: zinc-polyP nanoparticles in…
2020
The distinguished property of the physiological polymer, inorganic polyphosphate (polyP), is to act as a bio-intelligent material which releases stimulus-dependent metabolic energy to accelerate wound healing. This characteristic is based on the bio-imitating feature of polyP to be converted, upon exposure to peptide-containing body fluids, from stable amorphous nanoparticles to a physiologically active and energy-delivering coacervate phase. This property of polyP has been utilized to fabricate a wound mat consisting of compressed collagen supplemented with amorphous polyP particles, formed from the inorganic polyanion with an over-stoichiometric ratio of zinc ions. The proliferation and t…
Biomimetic Alginate/Gelatin Cross-Linked Hydrogels Supplemented with Polyphosphate for Wound Healing Applications
2020
In the present study, the fabrication of a biomimetic wound dressing that mimics the extracellular matrix, consisting of a hydrogel matrix composed of non-oxidized and periodate-oxidized marine alginate, was prepared to which gelatin was bound via Schiff base formation. Into this alginate/oxidized-alginate-gelatin hydrogel, polyP was stably but reversibly integrated by ionic cross-linking with Zn2+ ions. Thereby, a soft hybrid material is obtained, consisting of a more rigid alginate scaffold and porous structures formed by the oxidized-alginate-gelatin hydrogel with ionically cross-linked polyP. Two forms of the Zn-polyP-containing matrices were obtained based on the property of polyP to f…
Exploring the biological, catalytic, and magnetic properties of transition metal coordination complexes incorporating pyrophosphate
2019
Abstract Polyphosphate anions are ubiquitous in nature, none more so than the diphosphate tetra-anion P2O74−, commonly referred to as pyrophosphate (PPi). The past decade has seen a rise in the number of pyrophosphate coordination complexes synthesized and characterized, and the areas of research interest expanded to include magnetic, medicinal, nutraceutical, catalytic and bioinorganic. The aim of the present review is to collect and organize the multidisciplinary information of the inorganic pyrophosphate system paying special attention to the following points: (i) the structural diversity of the PPi-containing metal complexes from discrete species to coordination polymers, which is due t…
Inorganic polymeric phosphate/polyphosphate as an inducer of alkaline phosphatase and a modulator of intracellular Ca2+ level in osteoblasts (SaOS-2 …
2011
Inorganic polymeric phosphate is a physiological polymer that accumulates in bone cells. In the present study osteoblast-like SaOS-2 cells were exposed to this polymer, complexed in a 2:1 stoichiometric ratio with Ca(2+), polyP (Ca(2+) salt). At a concentration of 100 μM, polyP (Ca(2+) salt) caused a strong increase in the activity of the alkaline phosphatase and also an induction of the steady-state expression of the gene encoding this enzyme. Comparative experiments showed that polyP (Ca(2+) salt) can efficiently replace β-glycerophosphate in the in vitro hydroxyapatite (HA) biomineralization assay. In the presence of polyP (Ca(2+) salt) the cells extensively form HA crystallites, which r…
Self-Healing Properties of Bioinspired Amorphous CaCO3/Polyphosphate-Supplemented Cement
2020
There is a strong interest in cement additives that are able to prevent or mitigate the adverse effects of cracks in concrete that cause corrosion of the reinforcement. Inorganic polyphosphate (polyP), a natural polymer that is synthesized by bacteria, even those on cement/concrete, can increase the resistance of concrete to progressive damage from micro-cracking. Here we use a novel bioinspired strategy based on polyP-stabilized amorphous calcium carbonate (ACC) to give this material self-healing properties. Portland cement was supplemented with ACC nanoparticles which were stabilized with 10% (w/w) Na&ndash
A biomimetic approach to ameliorate dental hypersensitivity by amorphous polyphosphate microparticles.
2016
Abstract Objective Dental hypersensitivity has become one of the most common and most costly diseases in the world, even though those maladies are very rarely life threatening. Using amorphous microparticles, fabricated from the natural polymer (polyphosphate), we intend to reseal the dentinal tubules exposed and reduce by that the hypersensitivity. Methods Amorphous microparticles (termed aCa-polyP-MP) were prepared from Na-polyphosphate (polyP) and CaCl 2 , then incubated with human teeth. The potential of the microparticles to plug the dentinal tubules was determined by microscopic and spectroscopic techniques. Results We demonstrate that, in contrast to polyP, the aCa-polyP-MP efficient…