Assembly Mechanism of Highly Crystalline Selenium-Doped Hydroxyapatite Nanorods via Particle Attachment and Their Effect on the Fate of Stem Cells

Abstract

Hydroxyapatite is the main inorganic component of human bone. Synthetic hydroxyapatite and its different modified forms, which have been shown to be biocompatible and osteoconductive, have been widely used in bone tissue engineering. It is still challenging to controllably synthesize hydroxyapatite with a targeted morphology. In this work, we synthesized highly crystalline selenium-doped hydroxyapatite nanorods (SeHAN) via a two-step alcohol thermal method and provided a complete explanation of the synthesis mechanism. Tracing the crystals obtained from the solvated phase to the crystal phase with high-resolution microscopy, the nanorod formation route can be briefly described as follows: as a basic unit, ∼30 nm amorphous apatite initially formed in the first step and partly crystallized in early part of the second step; after a period of alcohol thermal reaction, immature nanorods appeared, which were composed of nanocrystals; finally, immature nanorods transformed into single-crystal nanorods through crystallization by particle attachment. Since few works have focused on the osteogenesis ability of SeHAN, whose antitumor effect has been widely studied, we investigated the influences of SeHAN on rat-bone-marrow-resident mesenchymal stem cells (MSCs). Surprisingly, SeHAN exhibited excellent biocompatibility for MSCs, enhanced their osteogenic differentiation, and inhibited their adipogenic differentiation. This work provides not only a general method to controllably synthesize hydroxyapatite nanorods/SeHAN but also an insight into understanding the hydroxyapatite formation mechanism. The current study also highlights the effects of SeHAN on MSCs that could furnish a significative strategy for manufacturing functional biomaterials for biomedical applications and tissue engineering by enhanced ossification and reduced marrow adiposity.

Layered Antimicrobial Selenium Nanoparticle–Calcium Phosphate Coating on 3D Printed Scaffolds Enhanced Bone Formation in Critical Size Defects

“…The enhanced bone formation in vivo is also supported by the in vitro results that suggested higher osteogenesis of MSCs when grown on the Se-CaP coating. The osteogenic properties of Se have been reported by other groups, − which showed the increased expression of osteogenesis genes (e.g., alkaline phosphatase, osteocalcin, and collagen-I) and osteogenesis activity with Se treatment.…”

Fucoidan-Mediated Anisotropic Calcium Carbonate Nanorods of pH-Responsive Drug Release for Antitumor Therapy

“…In addition, the biodegradable organic nanoparticles with anisotropy are usually difficult to synthesize ( Yang et al, 2018 ). Hence, the biocompatible nanoparticles such as mesoporous silica nanoparticles ( Kankala et al, 2020 ), hydroxyapatite nanoparticles ( Li et al, 2019 ; Tan et al, 2020 ), and calcium carbonate (CaCO 3 ) nanoparticles ( Chaudhary and Maiti, 2019 ) were considered for application in biomedicine.…”

3D-printed tri-element-doped hydroxyapatite/ polycaprolactone composite scaffolds with antibacterial potential for osteosarcoma therapy and bone regeneration

“…Combined with the results of the Se-HA, Sr-HA, Zn-HA, and HA, the Ca 2+ , PO 4 3− , and CO 3 2− dissolved from HA also promoted the osteogenic differentiation of BMSCs as well, whereas SeO 3 2− or Sr 2+ enhanced the proliferation and differentiation of BMSCs. It has been proved that both Se-HA and Sr-HA could promote the proliferation and differentiation of MSCs [ 78 , 79 ]. Se/Sr/Zn-HA contained the above ions, which can promote the proliferation and differentiation of BMSCs (Zn 2+ had no obvious effect), therefore, it presented a good potential for promoting bone differentiation.…”