Calcium phosphate materials such as hydroxyapatite (HA) or tricalcium phosphate (β-TCP) are highly attractive due to their multitude of applications in bone replacement as well as their environmental and ecological credentials. In this research, quail, hen, duck, and pigeon eggshells were used as a calcium source to obtain calcium phosphate materials via the environmentally friendly wet synthesis. Using the eggshells with the organic membrane, the biphasic calcium phosphate materials composed mainly of HA were obtained. The second mineral phase was β-TCP in the case of using quail, hen, and pigeon eggshells and octacalcium phosphate (OCP) in the case of duck eggshells. The HA content in the obtained materials depended on the amount of membrane in the eggshells and decreased in the order of pigeon, duck, hen, and quail eggshells. The eggshell membrane removal from the eggshells caused the reduced content of HA and the presence of the more soluble β-TCP or OCP phase in the obtained materials. The calcium ions release profile in the PBS buffer indicates the potential biomedical application of these materials.
Using the hen eggshells (biowaste) as a source of calcium and an environmentally friendly approach, the nanopowder composed of 74% of hydroxyapatite (HA) and 26% of β-tricalcium phosphate (β-TCP) was obtained. Due to the maximum reduction of the stages associated with the use of chemicals and energy, this method can be considered as economically and environmentally friendly. A well-developed surface area and the negative zeta potential at pH above 3.5 indicate good adsorption properties of this material. The obtained material shows high adsorption capacity towards Cu 2+ ions, i.e. 105.4 mg/g at pH 5. Good fit of the Langmuir adsorption model and the pseudo-second-order kinetic model may indicate chemical adsorption probably due to the electrostatic interactions between the Cu 2+ cations and the negatively charged phosphate and hydroxyl groups on the material surface.
In this study, calcium phosphate materials were obtained via a simple, eco-friendly wet synthesis method using hen eggshells as a calcium source. It was shown that Zn ions were successfully incorporated into hydroxyapatite (HA). The obtained ceramic composition depends on the zinc content. When doped with 10 mol % of Zn, in addition to HA and Zn-doped HA, DCPD (dicalcium phosphate dihydrate) appeared and its content increased with the increase in Zn concentration. All doped HA materials exhibited antimicrobial activity against S. aureus and E. coli. Nevertheless, fabricated samples significantly decreased preosteoblast (MC3T3-E1 Subclone 4) viability in vitro, exerting a cytotoxic effect which probably resulted from their high ionic reactivity.
In this study raw hen's eggshells were used as a calcium source for calcium phosphate mineral synthesis. The materials composed of brushite and different amounts of HA (hydroxyapatite) and β-TCP (β-tricalcium phosphate) with the needle-like, sheet-like and hexagonal structures were synthesized in the presence of the microwave. It was found that the time of microwave action, temperature and initial pH are parameters affecting the morphology and composition of the obtained materials, i.e. the increasing duration of MW exposure increases the amount of HA increases, whereas the temperature increase causes an increase in the contents of brushite and β-TCP. The lowering of initial pH leads to an increase in the brushite content.
A sufficient amount of ionic surfactants may induce a zeta potential of silica particles dispersed in water–glycol mixtures of about 100 mV in absolute value. Nanoparticles of silica were dispersed in 50-50 ethylene glycol (EG)–water and 50-50 propylene glycol (PG)–water mixtures, and the zeta potential was studied as a function of acid, base, and surfactant concentrations. The addition of HCl had a limited effect on the zeta potential. The addition of NaOH in excess of 10−5 M induced a zeta potential of about −80 mV in 50% EG, but in 50% PG the effect of NaOH was less significant. The addition of CTMABr in excess of 10−3 M induced a zeta potential of about +100 mV in 50% EG and in 50% PG. The addition of SDS in excess of 10−3 M induced a zeta potential of about −80 mV in 50% EG and in 50% PG. Long-chained analogs of SDS were even more efficient than SDS, but their application is limited by their low solubility in aqueous glycols.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.