Síntesis de hidroxiapatita dopada con silicio por el método de precipitación química convencional por vía húmeda

Abstract

In this work, the synthesis of hydroxyapatite and hydroxyapatite doped with silicon obtained from calcium nitrate tetrahydrate (Ca(NO3)2•4H2O) and egg shell (Ca(OH)2) were developed as sources of calcium; Phosphorus Pentaxide (P2O5), Potassium Phosphate Monobasic (KH2PO4) and Phosphoric Acid (H3PO4) as sources of phosphorus and Tetraethyl Ortosilicate (TEOS) as source of silicon; By the method of Conventional Chemical Precipitation by wet way. The powders hydroxyapatite and silicon-doped hydroxyapatite obtained were characterized by UV-Vis Molecular Absorption Spectrometry, Fourier Transform Infrared Spectroscopy (FITR) and RAMAN Spectroscopy. The compositional characterization given by UV-Vis molecular absorption spectrometry in the samples of hydroxyapatite evidences a Ca/P ratio between 1.69 -1.97 characteristic of hydroxyapatite and calcium-rich hydroxyapatite; In the silica-doped hydroxyapatite shows a Ca/P ratio 2.51 -3.78. A single and combined analysis of the spectra obtained from FTIR and RAMAN spectroscopy is performed, finding that hydroxyapatite is obtained for the method carried out with calcium nitrate tetrahydrate (Ca(NO3)2•4H2O) Monobasic Potassium Phosphate (KH2PO4). With the other precursors mentioned also hydroxyapatite and hydroxyapatite are obtained with possible substitution of silicon, but this only happens after the samples are submitted to the sintering process.