One-pot sol–gel synthesis of Sr/Ca-doped silica nanoparticles for osteogenic therapy in osteoporosis
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
Osteoporosis affects more than 200 million people worldwide, with an osteoporotic fracture occurring approximately every 3 seconds; with ageing populations, its prevalence continues to rise, yet it remains under-diagnosed and under-treated. Strontium- and calcium-doped mesoporous bioactive glass nanoparticles (BGNPs) are promising due to their ability to combine bioactive bone-regenerative function with controlled therapeutic ion release. We optimized a one-step sol–gel (modified Stöber) synthesis by varying the solvent system (pure water vs. 1:1 ethanol/water) to control BGNP size and morphology and assessed their effects on pre-osteoblasts (MC3T3-E1). Characterization by electron microscopy, X-ray photoelectron spectroscopy, and ^29Si MAS NMR showed that ethanol inclusion yielded smaller, uniform spherical particles (74 ± 5 nm), whereas water alone produced significantly larger particles (224 ± 42 nm). Both Sr2+ and Ca2+ were incorporated as network modifiers within an amorphous silicate framework, with no crystalline phases. Cytocompatibility assays revealed a size-dependent response: larger particles reduced cell viability at 1 μg/mL, while both sizes were biocompatible at 0.1 μg/mL. At the non-toxic concentration of 0.1 μg/mL, BGNPs enhanced alkaline phosphatase activity, promoted osteogenic differentiation, and exhibited antioxidant activity by scavenging tert-butyl hydroperoxide-induced free radicals. These results indicate that solvent-controlled synthesis effectively tunes BGNP size without disrupting silicate network integrity, and that properly sized Sr/Ca-doped BGNPs support both osteogenic and antioxidant responses, making them strong candidates for advanced therapeutic approaches in osteoporosis treatment.
Date Issued
2025-09-19
Date Acceptance
2025-08-29
Citation
Frontiers in Nanotechnology, 2025, 7
ISSN
2673-3013
Publisher
Frontiers Media S.A.
Journal / Book Title
Frontiers in Nanotechnology
Volume
7
Copyright Statement
© 2025 Palomeque Chávez, Mohammed, Aghajanpour, Li, Enzo, Kelly, Bradley, Kerherve, Porter, Hanna, Jones and Pinna. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
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Publication Status
Published
Article Number
1634210
Date Publish Online
2025-09-19