In 1967, Mayaharaet al. reported the localization of Alkaline phosphatase in the enamel organs. Sapir-Koren and Livshits explained about Pi/PPiratio, regulation of linked bone mineralization and phosphate homeostasis by inorganic forms of phosphate itself. Pyrophosphate (PPi) consisted of two molecules of inorganic phosphate (Pi) joined by a hydrolyzablehighenergyester bond.
High-polymeric inorganic polyphosphates were found in living organisms by L. Liberman in 1888. These compounds are linear polymers containing a few to several hundred residues of orthophosphate linked same as PPi. And, polyphosphate is food addictive for unfavorable metal ion chelater.
These findings can be concluded.
1. Phosphatase is localized at the place that calcifying.
2. Polyphosphate could be hydrolyzed to phosphate by the enzyme.
3. Polyphosphate can hold calcium ions by their chelate ability.
Therefore, Polyphosphate seems tobe a key substance of calcification. In spite of abundunt reports about preparation of Hydroxyapatite sinceMoreno et al. in 1968, we could not find the explanation about polyphosphate except for calcification inhibitor.
Preparation of Calcium OxideCalcium Oxide (Tateho Chemical Co.) were sintered 800ﾟ Cin electron furnace, Confirmed by X-Ray Diffraction Pattern.
Preparation of Polyphosphate 85% Ortho Phosphate (TOSOH NIKKEMI Co.） was placed in Silicon Carbide pot, stored in 200ﾟ C for few days, then 300ﾟ Cfor a week.
2g of Polyphosphate and 1.5 to 3.5g of Calcium oxide were placed in a pressure vessel(Fig.3), mixed and added 10ml of water, then stored in 200ﾟ C in electro furnace for 24 hours.
The chamber was cooled by current water, PH ware measured by indicator (PH Indecator Strip 109535, Merk) The slurry was washed until the PH goes neutralized, and dried.
Hydrothermal hydoxyapatite growth from Calcium oxide and Polyphosphate
Biomaterials and Technology Department of Conservative Dentistry, Showa University School of Dentistry
NARUSAWA Hideaki, OWADA Hiroyuki, TAKIGUCHI Yuichi, MIYAZAKI Takashi
Hypothesis and Objectives
MayaharaH, Hirano H, Saito T, Ogawa K. The new lead citrate method for the ultracytochemical demonstration of activity of non-specific alkaline phosphatase (orthophosphoric monoester phosphohydrolase). Histochemie. [Internet]. 1967 Jan;11(1):88–96. Available from: http://www.ncbi.nlm.nih.gov/pubmed/5589645
Sapir-koren R, Livshits G. Bone Mineralization and Regulation of Phosphate Homeostasis. 2011;8(6):286–300.
Lieberman, L.: Uber das Nuclein der Here und KunstlicheDarstellungeines Nucleus Eiweiss und Metaphosphatsaure. Bet. Chem.-Ges., 21 (1888), 598-607.
Moreno EC, Gregory TM, Brown WE. Preparation and Solubility of Hydroxyapatite. J. Res. Natl. Bur. Stand. - A. Phys. Chem. 1968;72(6):773–82.
ArendsJ, Schuthof J, Van der Linden WH. Bennema P. Van den Berg PJ (1979) reparation of pure hydroxyapatite single crystals by hydrothermal recrystallization. J Crystal Growth 46:213-220
Roy DM (1971)Ctystal growth of hydroxyapatile. Mat Res Bull 6:1337-1340
MengeotM. Hlarvill ML (1973) Gilliain OR. hydrothermal growth of calcium hydroxyapatite single crystals. I Crystal Growth 19:199-203
Results and Discussions
Materials and Method
As preliminary experiment, we mixed calcium oxide and polyphosphate, after exothermic reaction, it becomes the dry clot. The clots were moved to beaker and added a half-cup of water, then the water came to a boil again. After a few minutes, upper clear water indicates PH 3. By XRD analysis, precipitated powder assigned as Monetite and Calcium hydroxide mixture. No significant change was found at PH and chemical after a week.Calcium hydroxide should be reacted with water as usual; it seemed poly phosphate kept calcium hydroxide stable in acidic water by chelation.
I would like to thank RyojiTanaka, Sagami Chemical Research Institute in Kanagawa, Japan. He took beautiful crystal picture by Nikon digital SLR cameras with macro and ultra macro lenses.
Chemical reaction from polyphosphate and calcium oxide and hydroxide to apatite is shown in fig. 1. According to preliminary experiment, hydrolysis of polyphosphate doesn’t occurred at room temperature.
Nikon ECLIPSE ME600