Adsorption of Inositol Phosphate on Hydroxyapatite Powder with High Specific Surface Area

Abstract

Chelate-setting calcium-phosphate cements (CPCs) have been developed using inositol phosphate (IP6) as a chelating agent. However, the compressive strength of the CPC fabricated from a commercially available Hydroxyapatite (HAp) powder was approximately 10 MPa. In this study, we miniaturized HAp particles as a starting powder to improve the compressive strength of chelate-setting CPCs and examined the adsorption properties of IP6 onto HAp powders. An HAp powder with a specific surface area (SSA) higher than 200 m2/g (HApHS) was obtained by ultrasonic irradiation for 1 min in a wet synthesis process, greatly improving the SSA (214 m2/g) of the commercial powder without ultrasonic irradiation. The HApHS powder was found to be a B-type carbonate-containing HAp in which the phosphate groups in apatite were replaced by carbonate groups. Owing to the high SSA, the HApHS powder also showed high IP6 adsorption capacity. The adsorption phenomena of IP6 to our HApHS and commercially available Hap powders were found to follow the Freundlich and Langmuir models, respectively. We found that IP6 adsorbs on the HApHS powder by both physisorption and chemisorption. The fine HapHS powder with a high SSA is a novel raw powder material, expected to improve the compressive strength of chelate-setting CPCs.

Phosphorus Interactions with Iron in Undisturbed and Disturbed Arctic Tundra Ecosystems

“… As both chronic and episodic disturbances are becoming increasingly common across the Alaskan Arctic, we contend that this could limit potential P retention at wet sedge redox interfaces by inhibiting microbial Fe cycling and inducing a shift from primarily redox-controlled P interactions to those that are more susceptible to changes in pH. For example, Fe­(II) clays and Ca minerals are effective sorbents for phosphate and organic P ,− but are susceptible to dissolution and P release under acidic conditions (pH < ∼5). , Moreover, gravel mining may increase soil alkalinity and either enhance or inhibit P retention by promoting the coprecipitation of Ca phosphate species or raising the pH above the point of zero charge of soil minerals, respectively. − A further compounding factor is that gravel mining in our study area occurred approximately 50 years ago, yet biogenic Fe mats have never reestablished. This observation provides a striking example of the long-term impacts of mining disturbance on microbial Fe cycling, and in turn, the ability of wet sedge redox interfaces to recover and mediate P bioavailability in postmining landscapes.…”

“… 61 As both chronic and episodic disturbances are becoming increasingly common across the Alaskan Arctic, we contend that this could limit potential P retention at wet sedge redox interfaces by inhibiting microbial Fe cycling and inducing a shift from primarily redox-controlled P interactions to those that are more susceptible to changes in pH. For example, Fe(II) clays and Ca minerals are effective sorbents for phosphate and organic P 17 , 63 − 65 but are susceptible to dissolution and P release under acidic conditions (pH < ∼5). 22 , 23 Moreover, gravel mining may increase soil alkalinity and either enhance or inhibit P retention by promoting the coprecipitation of Ca phosphate species or raising the pH above the point of zero charge of soil minerals, respectively.…”

Phytic Acid Demonstrates Rapid Antibiofilm Activity and Inhibits Biofilm Formation When Used as a Surface Conditioning Agent

“…This might contradict previous research where “rougher” surfaces typically were thought to increase surface area and offer protection from shear forces for bacterial adhesion and biofilm formation ( 47 ). A recent study reported the high adsorption of IP6 into HA, where it was absorbed as monolayer ( 48 ). It could be that IP6 affects HA surface wettability and resulting charge, possibly due to IP6’s negatively charged phosphate group.…”

Deciphering competitive interactions: Phosphate and organic matter binding on goethite through experimental and theoretical insights

“…These aspects are significantly influenced by the diverse interactions of P with soil constituents involving free metal ions (Gros et al, 2019;Urrutia et al, 2013), soil minerals (Ahmed et al, 2019;Ganta et al, 2021;Kruse et al, 2015;Kubicki et al, 2012;Liu et al, 2022), and soil organic matter (Ahmed et al, 2018a;Debicka et al, 2023;Gros et al, 2017). Among these constituents, mineral surfaces such as Fe-and Al-(oxyhydr)oxides, calcium phosphates, silicates, and carbonates exhibit a strong affinity for binding phosphates (Bellier et al, 2006;Liu et al, 2012;Minamisawa et al, 2022;Okano et al, 2013;Tunesi et al, 1999). Notably, Fe-and Al-(oxyhydr)oxides play a pivotal role as the principal adsorbents of phosphates in soils (Borggaard, 2001;Borggaard et al, 2004;Elzinga and Sparks, 2007;Zhong et al, 2007).…”