DEVELOPMENT OF NOVEL BIOACTIVE PHOSPHATE GLASSES BY THE SOL-GEL METHOD: FROM MOLECULE TO MATERIAL

CHEMISTRY & GREEN CHEMISTRY

Lab: CIRIMAT

Duration: NanoX master Internship (8 months part-time in-lab immersion)

Latest starting date: 05/10/2026

Localisation: CIRIMAT and LCC at Toulouse INP - ENSIACET
4, allée E. Monso – CS 44362
31030 TOULOUSE - FRANC

Supervisors:
Jérémy SOULIÉ jeremy.soulie@toulouse-inp.fr
Jérôme VOLKMAN jerome.volkman@toulouse-inp.fr

This research master's degree project could be followed by a PhD

Work package:
This interdisciplinary research project,1-3 combining molecular synthesis and materials chemistry, aims to design and synthesize novel molecular precursors for the preparation of bioactive phosphate glasses via the sol–gel method, an approach that remains largely unexplored.4 In contrast to silicate-based bioactive glasses, which have been extensively investigated for their ability to promote bone regeneration through the controlled release of therapeutic ions and the subsequent formation of an apatite layer, sol-gel-derived phosphate glasses remain poorly studied despite their considerable potential for the regeneration of both hard and soft tissues.5 This project therefore seeks to develop a new generation of bioactive biomaterials with innovative and enhanced regenerative properties. Mesoporous bioactive phosphate glasses are generally synthesized using a common sol-gel approach based on trialkyl phosphates as the inorganic phosphate source under mild reaction conditions.6-8 The precursors are typically dissolved in a basic or acidic hydroalcoholic solution at room temperature, yielding either a sol or a gel depending on the nature of the precursors. However, these results are in contradiction with the extensive knowledge on trialkylphosphate hydrolysis. Work Package 1: The candidate will first investigate the hydrolysis products generated during reported6-8 sol–gel synthesis routes and establish correlations between these products, the structural characteristics, and the properties of phosphate glass materials during calcination. Work Package 2: The candidate will then characterize the products obtained from a novel sol-gel synthesis route, not yet reported in the literature, developed within our respective teams. The candidates will also establish correlations between these products, the structural evolution, and the properties of phosphate glass materials during calcination.

References:
1. Vecchio, G.; Darcos, V.; Grill, S. L.; Brouillet, F.; Coppel, Y.; Duttine, M.; Pugliara, A.; Combes, C.; Soulié, J. Spray-Dried Ternary Bioactive Glass Microspheres: Direct and Indirect Structural Effects of Copper-Doping on Acellular Degradation Behavior, Acta Biomater. 2024, 181, 453–468. 2. Lagarrigue, P.; Darcos, V.; Tenailleau, C.; Duployer, B.; Dupret-Bories, A.; Cazalbou, S.; Poquillon, D.; Grossin, D.; Combes, C.; Soulié, J. Poly(D,Llactide)-Grafted Bioactive Glass Nanoparticles: From Nanobricks to Freeze-Cast Scaffolds for Bone Substitution, ACS Appl. Nano Mater. 2022, 5 (4), 5278–5291. 3. Soulié, J.; Gras, P.; Marsan, O.; Laurencin, D.; Rey, C.; Combes, C. Development of a New Family of Monolithic Calcium (Pyro)Phosphate Glasses by Soft Chemistry. Acta Biomater, 2016, 41, 320–327. 4. Lepry, W. C. A Review of Phosphate and Borate Sol–Gel Glasses for Biomedical Applications, 2021. 5. Kargozar, S.; Singh, R. K.; Kim, H.- W.; Baino, F. “Hard” Ceramics for “Soft” Tissue Engineering: Paradox or Opportunity? Acta Biomater. 2020, 115, 1–28. 6. Bueno, O. M. V. M.; Herrera, C. L.; Bertran, C. A.; San-Miguel, M. A.; Lopes, J. H. An Experimental and Theoretical Approach on Stability towards Hydrolysis of Triethyl Phosphate and Its Effects on the Microstructure of Sol-Gel-Derived Bioactive Silicate Glass, Mater. Sci. Eng. C 2021, 120, 111759. 7. Carta, D.; Pickup, D. M.; Knowles, J. C.; Smith, M. E.; Newport, R. J. Sol–Gel Synthesis of the P2O5–CaO–Na2O– SiO2 System as a Novel Bioresorbable Glass, 2005. 8. Pickup, D. M.; Guerry, P.; Moss, R. M.; Knowles, J. C.; Smith, M. E.; Newport, R. J. New Sol-Gel Synthesis of a (CaO)0.3(Na2O)0.2(P2O5)0.5 Bioresorbable Glass and Its Structural Characterisation, J. Mater. Chem. 2007, 17 (45), 4777–4784.

Areas of expertise:
Molecular synthesis, Sol-Gel, Materials, Phosphate Glasses

Required skills for the internship:
The candidate should have a strong background in molecular synthesis under anhydrous and inert atmosphere conditions. They should also be motivated to develop expertise in materials characterization techniques, including SAXS, BET surface area analysis, microscopy (MET, MEB FEG), and solid-state NMR spectroscopy.