Application of Statistical Experimental Design and Surface Plot Technique to Optimize Oxygenated Apatite Synthesis

Soumia Belouafa,Khalid Digua,Hassan Chaair

doi:10.1155/2020/1034959

Abstract

This work deals with oxygenated apatite synthesis from calcium chloride and phosphoric acid using a wet precipitation method. An experimental design is applied to precise the influence of the synthesis parameters (pH of the reaction medium, atomic ratio Ca/P of the reagents, concentration of the calcium solution (Ca2+), temperature of the reaction medium (T), and duration of the reaction (D)) on the chemical composition (Ca/P molar ratio, % O2, and % O22−). An empirical model was developed and validated by applying the ANOVA analysis incorporating the interaction effects of all parameters and optimized using the response surface methodology. A reproducible synthesis of more oxygenated apatite with speed of dissolution adaptable to that of the osseous neoformation and allowing a progressive diffusion of oxygenated species (Ca/P = 1.575) is attained.

Highlights

Oxygenated apatites based on calcium phosphate have a wide range of potential applications for bone and dental substitutes because of their antibacterial properties, which make them able to limit the proliferation of microorganisms at the site of implantation [1,2,3]. ese properties are due to the oxygenated species contained in the channels of the apatite structure [1,2,3]. ese species are liberated in the living environment either by progressive dissolution of the material or by chemical exchange with the living environment [1]
Our work is concerned to modelize and optimize this synthesis process by applying the experimental design and response surface methodologies. ese methodologies are essential in engineering to improve the performance of a manufacturing process. ey are widely employed in the development of new processes. e application of experimental design and response surface techniques during the initial phase of process development can lead to improved process performance, less variability, shorter development time, and reduced overall cost [7]
Powder Synthesis. e preparation of phosphocalcic oxygenated apatite was performed by the precipitation reaction with calcium and phosphate solutions. e calcium solution was prepared by adding calcium chloride (CaCl2) in 250 mL of oxygenated water (30%). e phosphate solution was prepared by adding phosphoric acid (84%) in 250 mL of oxygenated water (30%). e method of synthesis consists in putting the calcium solution into a reactor maintained at the temperature of synthesis. e pH was adjusted by manual

Summary

Research Article

Received 5 March 2020; Revised 7 May 2020; Accepted 2 June 2020; Published 24 June 2020. Is work deals with oxygenated apatite synthesis from calcium chloride and phosphoric acid using a wet precipitation method. An experimental design is applied to precise the influence of the synthesis parameters (pH of the reaction medium, atomic ratio Ca/P of the reagents, concentration of the calcium solution (Ca2+), temperature of the reaction medium (T), and duration of the reaction (D)) on the chemical composition (Ca/P molar ratio, % O2, and % O2 2−). An empirical model was developed and validated by applying the ANOVA analysis incorporating the interaction effects of all parameters and optimized using the response surface methodology. A reproducible synthesis of more oxygenated apatite with speed of dissolution adaptable to that of the osseous neoformation and allowing a progressive diffusion of oxygenated species (Ca/P 1.575) is attained

Introduction

Materials and Methods

Responses pH

DF SS