Preparation of calcium phosphate coatings on titanium implant materials by simple chemistry

Abstract

A two-step chemical treatment has been developed in our group to prepare commercially pure titanium (cpTi) surfaces that will allow calcium phosphate (Ca-P) precipitation during immersion in a supersaturated calcification solution (SCS) with ion concentrations of [Ca2+] = 3.10 mM and [HPO4(2-)] = 1.86 mM. It was observed that a precalcification (Pre-Ca) procedure prior to immersion could significantly accelerate the Ca-P deposition process. In this work, the bioactivity of chemically treated cpTi and Ti6Al4V was further verified by applying commercially available Hanks' balanced salt solution (HBSS), an SCS with very low ion concentrations of [Ca2+] = 1.26 mM and [HPO4(2-)] = 0.779 mM, as the immersion solution. It was found that a uniform and very dense apatite coating magnesium impurities was formed if the Pre-Ca procedure was performed before immersion, as compared with the loose Ca-P layer obtained from the abovementioned high concentration of SCS. The formation of a microporous titanium dioxide thin surface layer on cpTi or Ti6Al4V by the two-step chemical treatment could be the main reason for the induction of apatite nucleation and growth from HBSS. Variations of pH values, Ca and P concentrations, and immersion time in HBSS were investigated to reveal the detailed process of Ca-P deposition. The described treatments provide a simple chemical method to prepare Ca-P coatings on both cpTi and Ti6Al4V.

Physicochemical Properties and Applications of Poly(lactic-co-glycolic acid) for Use in Bone Regeneration

“…[99][100][101] Moreover, PLGA spheres have been combined with apatitic nanoparticles 102,85 to reduce fibrous encapsulation of PLGA, promoting new bone ingrowth while enhancing direct bone contact. [103][104][105][106][107][108][109][110][111] Porosity can be created in tissue-engineered scaffolds by the incorporation of PLGA spheres, as a porous scaffold is gradually formed on degradation of PLGA spheres. Degradation of injectable calcium phosphate cements has been accelerated considerably by the incorporation of PLGA microspheres into the injectable paste.…”

Strontium and Silicon Co-Doped Apatite Coating: Preparation and Function as Vehicles for Ion Delivery

“…ICP-OES analysis also indicated that the Sr content in the coating was lower than that of silicon which could explain why the coating in this study was similar to pure HA. The soaking method used in this study has previously been shown to give an apatite coating that is calcium deficient and with poor crystallinity [24][25][26]. The Ca/P ratios for all coatings prepared with different soaking temperatures and with different ion concentrations of Sr and Si ions in the solution were below that for stochiometric hydroxyapatite, i.e.…”

Bioactivity of a Ni-Free Ti-Based Metallic Glass

“…Ti-OH groups are also presented on the porous TiO 2 surface. 24) Negative-charged and micro-porous surfaces are the main reason for the good bioactivity. 25) Step two of pre-calcification treatment stimulates the adsorption of HPO 4 2À and Ca 2þ , which are necessary for the nucleation of apatite.…”