Evaluating in vitro calcium phosphate formation on the surfaces of synthesized silanated polymethylmethacrylate microspheres

Mohammadi, Fatemeh; Hesaraki, Saeed; Naghizadeh, Rahim; Nezafati, Nader; Beygzadeh, Mojtaba

doi:10.30501/acp.2025.538730.1182

Evaluating in vitro calcium phosphate formation on the surfaces of synthesized silanated polymethylmethacrylate microspheres

Document Type : Original Research Article

Authors

Fatemeh Mohammadi ¹

Saeed Hesaraki ²

Rahim Naghizadeh ³

Nader Nezafati ⁴

Mojtaba Beygzadeh ⁵

¹ Nanotechnology and Advanced Materials department, Materials and Energy Research Center

² Department of Nanotechnology & Advanced Materials, Materials and Energy Research Center, Meshkindasht, Alborz, Iran

³ School of Materials and Metallurgical Engineering Iran University of Science and Technology, Tehran, Iran

⁴ Department of Nanotechnology and Advanced Materials, Materials and Energy Research Center, Karaj, Iran

⁵ Department of Energy, Materials and Energy Research Center, Karaj, Iran

10.30501/acp.2025.538730.1182

Abstract

Polymethyl methacrylate (PMMA) bone cement is widely used in orthopedics due to its suitable mechanical properties; however, its limited bioactivity remains a major challenge for effective bonding with bone. In this study, a chemical surface modification strategy was investigated to enhance the bioactivity of PMMA microspheres. The microspheres were synthesized using a solvent evaporation method, resulting in particle sizes ranging from 4 to 21 μm. Acid hydrolysis with 30 wt% sulfuric acid was performed to introduce carboxylic groups, which were further functionalized through silanization with (3-glycidyloxypropyl) trimethoxysilane (GPTMS) and tetraethoxysilane (TEOS) at different ratios (GPTMS:TEOS = 3:2, 2.5:1.5, and 2:1). FTIR and SEM analyses confirmed successful surface modification without altering the spherical morphology. In vitro bioactivity assessment in simulated body fluid (SBF) revealed the progressive deposition of hydroxyapatite on the surface after 7 and 14 days, as verified by SEM, FTIR, and XRD. These findings indicate that silane-based surface modification can effectively improve the bioactivity of PMMA microspheres.

Keywords

Polymethylmethscrylate

Y-Glycidoxypropyltrimethoxysilane

Tetraethylorthosilicate

Surface modification

Silanization

Subjects