Block-copolymer-assisted synthesis of hydroxyapatite nanoparticles with high surface area and uniform size

Abstract

We report the synthesis of hydroxyapatite nanoparticles (HANPs) by the coprecipitation method using calcium D-gluconate and potassium hydrogen phosphate as the sources of calcium and phosphate ions, respectively, and the triblock copolymer F127 as a stabilizer. The HANPs were characterized using scanning electron microscopy, x-ray diffraction, and nitrogen adsorption/desorption isotherms. Removal of F127 by solvent extraction or calcination alters the structure of HANPs. The solvent-extracted HANPs were single crystals with their 001 axis oriented along the rod axis of the HANP, whereas the calcined HANPs contained two crystal phases that resulted in a spherical morphology. The calcined HANPs had much higher surface area (127 m 2 g −1 ) than the solvent-extracted HANPs (44 m 2 g −1 ).

Synthesis of rod-like hydroxyapatite with high surface area and pore volume from eggshells for effective adsorption of aqueous Pb(II)

“…However, by controlling addition of phosphorous precursor with a syringe pump, pH control during RHNP synthesis may not be necessary. The addition rate of the acid precursor was controlled with the pump such that the pH of the reaction solution was within basic conditions favorable for RHNP formation and maturation [20]. We implemented several addition rates (25,50,100,200, and 400 ml/h) to test the assumption.…”

“…Then again, the pH value increased slightly to about 11.50 after 30 min reaction (Table 1). These are typical pH values for reaction solutions that favor production of stoichiometric [20] and rod-like particles [21].…”

Hydroxyapatite Nanoparticle Coating on Polymer for Constructing Effective Biointeractive Interfaces

“…Journal of Nanomaterials and (ii) organic molecules such as amino acids [53], polymers [54,55], and surfactants like cetyltrimethylammonium bromide (CTAB) [56]. For example, CTAB has been used as a rod-like micelle template (see Figures 2(a) and 2(b)).…”

Biodegradable and Biocompatible Systems Based on Hydroxyapatite Nanoparticles

“…Porous HAp particles can be prepared according to a great diversity of methods [11] such as self-assembly [12][13][14][15], spray drying [16], double emulsion [17], solvothermal [18], sol-gel [19] and hydrothermal [20][21][22][23].…”