Strontium-doped Hydroxyapatite Research Articles

Preparation and Characterization of Carboxymethyl Chitosan/Sodium Alginate Composite Hydrogel Scaffolds Carrying Chlorhexidine and Strontium-Doped Hydroxyapatite

Preparation and Characterization of Carboxymethyl Chitosan/Sodium Alginate Composite Hydrogel Scaffolds Carrying Chlorhexidine and Strontium-Doped Hydroxyapatite

Study on the performance and mechanism of cobaltous ion removal from water by a high-efficiency strontium-doped hydroxyapatite adsorbent.

In this study, a high-efficiency strontium-doped hydroxyapatite (Sr-HAP) adsorbent was synthesized by a sol-gel method for removing cobaltous ions (Co(II)) from water. The effects of adsorbent dose, initial solution pH, initial Co(II) concentration and temperature on the removal performance of Co(II) were investigated. Experimental results indicated that the optimum Sr-HAP dose was 0.30g/50mL solution, the Sr-HAP adsorbent could effectively remove Co(II) in a wide pH range of 3-8. Increasing temperature was conducive to the adsorption, and the maximum Co(II) adsorption capacity by Sr-HAP reached 48.467mg/g at 45°C. The adsorption of Co(II) followed the pseudo-second-order kinetic model, indicating that the Co(II) adsorption by Sr-HAP was attributed mainly to chemisorption. The isothermal adsorption results showed that at lower Co(II) equilibrium concentration, the Langmuir model fitted the data better than the Freundlich model but opposite at higher Co(II) equilibrium concentration. Therefore, the adsorption of Co(II) was a process from monolayer adsorption to multilayer adsorption with the increase of the Co(II) equilibrium concentration. The diffusion analysis of Co(II) to Sr-HAP indicated that the internal diffusion and surface adsorption were the rate-controlled steps of Co(II) adsorption. Thermodynamic study demonstrated that the Co(II) adsorption process was spontaneous and endothermic. The mechanism study revealed that in addition to chemisorption, Sr-HAP also removed Co(II) ions from water via ion exchange and surface complexation.

Comparison between Two Different Synthesis Methods of Strontium-Doped Hydroxyapatite Designed for Osteoporotic Bone Restoration.

Development of efficient controlled local release of drugs that prevent systemic side effects is a challenge for anti-osteoporotic treatments. Research for new bone-regeneration materials is of high importance. Strontium (Sr) is known as an anti-resorptive and anabolic agent useful in treating osteoporosis. In this study, we compared two different types of synthesis used for obtaining nano hydroxyapatite (HA) and Sr-containing nano hydroxyapatite (SrHA) for bone tissue engineering. Synthesis of HA and SrHA was performed using co-precipitation and hydrothermal methods. Regardless of the synthesis route for the SrHA, the intended content of Sr was 1, 5, 10, 20, and 30 molar %. The chemical, morphological, and biocompatibility properties of HA and SrHA were investigated. Based on our results, it was shown that HA and SrHA exhibited low cytotoxicity and demonstrated toxic behavior only at higher Sr concentrations.

Strontium-Doped Hydroxyapatite Coating Improves Osteo/Angiogenesis for Ameliorative Graft-Bone Integration via the Macrophage-Derived Cytokines-Mediated Integrin Signal Pathway.

Polyethylene terephthalate (PET) artificial ligaments, renowned for their superior mechanical properties, have been extensively adopted in anterior cruciate ligament (ACL) reconstruction surgeries. However, the inherent bio-inertness of PET introduces formidable barriers to graft-bone integration, a critical aspect of rehabilitation. Previous interventions, ranging from surface roughening to chemical modifications, have aimed to address this challenge; however, consistently effective techniques for inducing graft-bone integration remain scarce. Our study employed advanced surface-coating methodologies to introduce strontium-doped hydroxyapatite (SrHA) onto PET ligaments. Detailed scanning electron microscopy (SEM) examinations revealed a uniform and integrative coating of SrHA on PET fibers. Furthermore, spectroscopic analysis confirmed the steady release of strontium ions from the coated surface under physiological conditions. In-depth cellular studies proved that extracellular strontium emanating from SrHA-coated PET (PET@SrHA) ligaments actively steers the M2 macrophage polarization. Additionally, macrophages (Mφs) manifested a heightened secretion of prohealing cytokines when exposed to PET@SrHA. Subsequent investigations showed that these cytokines acted as mediators, activating integrin signaling pathways among macrophages, vascular endothelial cells, and osteoblasts. As a direct consequence, an increased rate of angiogenesis and osteogenic differentiation was observed, vital for graft-bone integration following ACL reconstruction with PET@SrHA ligaments. From a biochemical standpoint, our results pinpoint strontium ions as influential immunomodulators, sculpting the graft-bone interface's immune environment. This insight presents the SrHA-coating technique as a viable therapeutic strategy, holding sound promise for improving angiogenesis and osseointegration outcomes during ACL reconstruction using PET-based grafts.

Biomimetic hydroxyapatite and strontium-doped derivatives from crab shells and their ingenious scaffold fabrication for bone tissue engineering

The success of the most commonly used bio-ceramics in current medicine, hydroxyapatite (HAp), is due to its similar chemical and structural properties with the human bone tissue. The current research aims to calcine crab shells, a bio-waste source, to synthesize HAp, and dope it with strontium (Sr) to use it as a sustainable and economical source for bone tissue engineering. Different temperatures (900°, 1000°, and 1100 °C) were used for the calcination process. FE-SEM analysis showed the importance of temperature for morphology. The variance in the Ca/P ratio was revealed by EDX analysis. The higher the calcination temperature, the more pronounced were the peaks of HAp and (β-Tricalcium Phosphate) β-TCP were revealed by X-Ray Diffraction (XRD) analysis. Moreover, as the concentration of Sr2+ increased, both the crystallite size and crystallinity index (CI) of HAp decreased, as confirmed by XRD analysis. ATR-FTIR analysis showed the best-defined bond types (O-H, P-O, etc.). TGA and DSC analysis revealed the loss of adsorbed water and the appearance of endothermic peaks, respectively. To create a possible bone transplant substitute, scaffolds from HAp and strontium-doped HAp (Sr-HAp) were prepared utilising the foam replica method. At a Sr2+ doping of 1% (w/w) and a calcination temperature of 1100 °C, the highest percent cell viability was obtained, as determined by the MTT test. These results indicate that the concentration of the dopant (Sr2+) have a significant influence on the properties of the final material suitable for bone regeneration in situ.

Probing the influence of strontium doping and annealing temperature on the structure and biocompatibility of hydroxyapatite nanorods.

Among numerous biologically important metal cations, strontium (Sr2+) has received much attention in bone tissue regeneration because of its osteoinductive properties combined with its ability to inhibit osteoclast activity. In this study, strontium-doped hydroxyapatite (Sr-HAp) nanorods with varying molar ratios of Ca : Sr (10 : 0, 9 : 1, 5 : 5, 3 : 7 and 0 : 10) were synthesized using the chemical precipitation technique. The synthesized Sr-HAp nanostructures were characterized using powder X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy, energy dispersive X-ray spectroscopy, and Raman and Fourier transform infrared (FTIR) spectroscopies to understand their structural and morphological features, and composition. XRD results revealed the formation of HAp nanostructures, whose unit cell volume increased as a function of the dopant level. The reaction process investigation showed the formation of hydroxyapatite (HAp), strontium apatite (SAp) and various Sr-HAp phases. FESEM micrographs displayed the morphological transformation of Sr-HAp from nanorods to nanosheets upon increasing the dopant level. In the FTIR spectra, the bands of the PO43- group shifted towards a lower wavenumber upon increasing the dopant concentration in Sr-HAp that signifies the structural distortion due to the presence of a large amount of strontium ions. The peaks of PO43- and OH- vibrations in the Raman spectra were further analysed to corroborate the structural distortion of Sr-HAp. Selected area electron diffraction patterns obtained using TEM reveal the reduced crystallinity of Sr-HAp due to Sr-doping, which is in line with the XRD results. Finally, the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay showed that the synthesized Sr-HAp has no toxic effect on the survival and growth of mesenchymal stem cells. In summary, the synthesized novel Sr-HAp nanorods exhibit great promise for bone tissue engineering applications.

Evaluation of osteogenic properties of a novel injectable bone-repair material containing strontium in vitro and in vivo.

Objective: This study aims to develop and evaluate the biocompatibility and osteogenic potential of a novel injectable strontium-doped hydroxyapatite bone-repair material. Methods: The properties of strontium-doped hydroxyapatite/chitosan (Sr-HA/CS), hydroxyapatite/chitosan (HA/CS) and calcium phosphate/chitosan (CAP/CS) were assessed following their preparation via physical cross-linking and a one-step simplified method. Petri dishes containing Escherichia coli and Staphylococcus epidermidis were inoculated with the material for in vitro investigations. The material was also co-cultured with stem cells derived from human exfoliated deciduous teeth (SHEDs), to assess the morphology and proliferation capability of the SHEDs, Calcein-AM staining and the Cell Counting Kit-8 assay were employed. Osteogenic differentiation of SHEDs was determined using alkaline phosphatase (ALP) staining and Alizarin Red staining. For in vivo studies, Sr-HA/CS was implanted into the muscle pouch of mice and in a rat model of ovariectomy-induced femoral defects. Hematoxylin-eosin (HE) staining was performed to determine the extent of bone formation and defect healing. The formation of new bone was determined using Masson's trichrome staining. The osteogenic mechanism of the material was investigated using Tartrate-resistant acid phosphatase (TRAP) staining and immunohistochemical studies. Results: X-ray diffraction (XRD) and energy-dispersive spectroscopy (EDS) showed that strontium was successfully doped into HA. The Sr-HA/CS material can be uniformly squeezed using a syringe with a 13% swelling rate. Sr-HA/CS had a significant antibacterial effect against both E. coli and S. epidermidis (p < 0.05), with a stronger effect observed against E. coli. The Sr-HA/CS significantly improved cell proliferation and cell viability in vitro studies (p < 0.05). Compared to CAP/CS and CS, Sr-HA/CS generated a substantially greater new bone area during osteoinduction experiments (p < 0.05, p < 0.001). The Sr-HA/CS material demonstrated a significantly higher rate of bone repair in the bone defeat studies compared to the CAP/CS and CS materials (p < 0.01). The OCN-positive area and TRAP-positive cells in Sr-HA/CS were greater than those in control groups (p < 0.05). Conclusion: A novel injectable strontium-doped HA bone-repair material with good antibacterial properties, biocompatibility, and osteoinductivity was successfully prepared.

Gelatin-mediated gallium-doped SrHA composite coatings with sequential antimicrobial and osteogenic functions for infected bone defect repair

In this study, gallium- and gelatin-modified strontium-doped hydroxyapatite (SrHA-Gel-Ga) bilayer coatings were prepared on titanium substrates by electrodeposition and spin-coating techniques. The results showed that gallium and gelatin were uniformly doped into the SrHA coatings, which exhibited good hydrophilicity and bioactivity. Furthermore, SrHA-Gel-Ga demonstrated good antimicrobial properties against E. coli and S. aureus, especially S. aureus. The co-doping of Sr and gelatin in the coatings was effective in mitigating the cytotoxicity of Ga. SrHA-Gel-Ga was better able to promote the adhesion, proliferation and early differentiation of MC3T3-E1 cells. This study provides a new strategy for the development of anti-infective bone repair coatings.

Bone Regeneration in Small and Large Segmental Bone Defect Models after Radiotherapy Using Injectable Polymer-Based Biodegradable Materials Containing Strontium-Doped Hydroxyapatite Particles

The reconstruction of bones following tumor excision and radiotherapy remains a challenge. Our previous study, performed using polysaccharide-based microbeads that contain hydroxyapatite, found that these have osteoconductivity and osteoinductive properties. New formulations of composite microbeads containing HA particles doped with strontium (Sr) at 8 or 50% were developed to improve their biological performance and were evaluated in ectopic sites. In the current research, we characterized the materials by phase-contrast microscopy, laser dynamic scattering particle size-measurements and phosphorus content, before their implantation into two different preclinical bone defect models in rats: the femoral condyle and the segmental bone. Eight weeks after the implantation in the femoral condyle, the histology and immunohistochemistry analyses showed that Sr-doped matrices at both 8% and 50% stimulate bone formation and vascularization. A more complex preclinical model of the irradiation procedure was then developed in rats within a critical-size bone segmental defect. In the non-irradiated sites, no significant differences between the non-doped and Sr-doped microbeads were observed in the bone regeneration. Interestingly, the Sr-doped microbeads at the 8% level of substitution outperformed the vascularization process by increasing new vessel formation in the irradiated sites. These results showed that the inclusion of strontium in the matrix-stimulated vascularization in a critical-size model of bone tissue regeneration after irradiation.

Biomimetic Mineralization of Fibrillar Collagen with Strontium-doped Hydroxyapatite

Fibrillar collagen structures mineralized with hydroxyapatite using the polymer-induced liquid precursor (PILP) process have been explored as synthetic models for studying biomineralization of human hard tissues and have also been applied in the fabrication of scaffolds for hard tissue regeneration. Strontium has important biological functions in bone and has been used as a therapeutic agent for treating diseases that result in bone defects, such as osteoporosis. Here, we developed a strategy to mineralize collagen with Sr-doped hydroxyapatite (HA) using the PILP process. Doping with Sr altered the crystal lattice of HA and inhibited the degree of mineralization in a concentration-dependent manner, but did not affect the unique formation of intrafibrillar minerals using the PILP. The Sr-doped HA nanocrystals were aligned in the [001] direction but did not recapitulate the parallel alignment of the c-axis of pure Ca HA in relation to the collagen fiber long axis. The mimicry of doping Sr in PILP-mineralized collagen can help understand the doping of Sr in natural hard tissues and during treatment. The fibrillary mineralized collagen with Sr-doped HA will be explored in future work as biomimetic and bioactive scaffolds for regeneration of bone and tooth dentin.

Sr2+-dependent microstructure regulation of biodegradable Sr-doped hydroxyapatite microspheres with interconnected porosity for sustained drug delivery

The microstructure and compositional tunability of hydroxyapatite (HA) microspheres, as well as their limited biodegradability, have been challenges for their use as carriers in drug delivery systems. In this study, strontium-doped HA (Sr-HA) microspheres with interconnected porosity and pore channels were successfully prepared under the regulation of Sr2+ via a hydrothermal method. The morphologies, scales, constituents, and pore geometries of Sr-HA microspheres were modulated by the concentration of Sr2+. SEM and TEM observations revealed that diverging, dense flower-like, hierarchical porous, and trumpet-shaped macroporous microspheres were obtained as Sr/(Sr + Ca) ratio increased. Correspondingly, the size of the microspheres decreased from approximately 120 μm–15 μm. The introduction of Sr2+ significantly enhanced the biodegradability of the microspheres. Furthermore, the porous Sr-HA microspheres showed superior vancomycin loading capacity (167.5 mg/g) and sustained release properties. This possible microstructure regulation mechanism was discussed based on the experimental results. This study provides a new perspective on material design for various potential applications.

Dual-functional coatings on magnesium alloys: Enhancing corrosion behavior under stress and osteogenic effect in osteoporotic rats

Magnesium-based implants are subjected to complicated stresses during implantation in the human body. In this case, they undergo stress-induced corrosion and usually lead to early breakage or disintegration of implants. Calcium phosphate compounds have been used as coatings, bone cement and drug carrier in orthopedic application. Their success has been expanded to Mg alloys. Calcium phosphate-based coatings succeeded in corrosion control and osteointegration of Mg alloys in a big extent. However, their protective effect under stress condition is questionable considering the brittle nature. With the assistance of high pH microenvironment near Mg alloy surface, calcium phosphate coatings have the self-repair potential via the dissolution-precipitation mechanism. Inspired by this phenomenon, strontium doped hydroxyapatite (Sr-HA) coatings with higher solubility have been prepared on the surface of Mg alloys. Sr-HA coatings served as not only a physical barrier effect to postpone pitting formation, but also provide ion supplement to seal the cracks initiated during tensile deformation. The results obtained in slow strain rate tensile test (SSRT) demonstrated improved corrosion and mechanical behaviors of Sr-HA coated Mg alloys. Specifically, the elongation of Sr-HA coated alloy increased by 56.7 and 35.2% as compared to the bare and HA coated one in DMEM. In ovariectomized rats, the implants exhibited only 2.7–5.6% reduction of implant volume after 12 weeks implantation. Sr-HA coating further increased early new bone formation than HA coated implants. 12 weeks post-implantation, a large amount of bony tissue with higher trabecular thickness and hardness was formed adjacent to the Sr-HA coated implants. This study demonstrated the efficiency of a rapid dissolved Sr-HA coating on the corrosion behavior of Mg alloys under mechanical loading and the osteogenesis in ovariectomized rats. It therefore holds a promising practical significance for the future coating design strategy for Mg alloys when trying to expand their application range to locations with higher loading conditions.

Strontium-Doped Hydroxyapatite Nanowires with a Hierarchical Interface: Enhancing Osteoinduction and Cellular Attachment

Strontium-doped hydroxyapatite nanowires with hierarchical interfaces were prepared in this study by a one-step hydrothermal method using Pluronic123 as a structural guide. The cytotoxicity and biocompatibility of the materials were detected by the MTT assay. The adhesion and growth of MG63 (osteosarcoma cells) on materials with different doping ratios were observed by scanning electron microscopy and fluorescence microscopy. Real-time polymerase chain reaction (RT-PCR) was used to detect the transcription levels of alkaline phosphatase (ALP), Runt-associated transcription factor 2 (Runx2), osteopontin (OPN), type I collagen (Coll-I) and osteocalcin (OCN). The protein expression levels of ALP, Runx2, OPN, Col-I and OCN were detected by western blotting (WB). The results showed that strontium-doped hydroxyapatite nanowires had good biocompatibility and osteogenic induction ability, and the strontium-doped hydroxyapatite nanowires with a 1% strontium content exhibited a better osteogenic induction performance. Therefore, it is expected to become a new, promising bone induction scaffold material.

Strontium-doped hydroxyapatite as an efficient adsorbent for Cd(II) removal from wastewater: Performance, kinetics, and mechanism

A strontium-doped hydroxyapatite (Sr-HAP) adsorbent was synthesized by a sol–gel method and used to remove Cd(II) from wastewater. The adsorption performance of the as-prepared Sr-HAP and the kinetics and mechanism of Cd(II) removal were investigated. The experimental results showed that the Sr-HAP adsorbent achieved the maximum Cd(II) adsorption capacity (158.30 mg/g) at a temperature of 298 K, an adsorbent dosage of 0.08 g/50 mL, and an initial solution pH of 6. The adsorption of Cd(II) onto the Sr-HAP adsorbent was well described by the Langmuir isothermal adsorption model and pseudo-second-order kinetic model, and was found to follow a monolayer chemisorption process. In addition, the internal diffusion model was also used to fit the experimental data. The results indicated that the Cd(II) adsorption process was controlled by both internal diffusion and surface adsorption. Thermodynamic analysis revealed that the Cd(II) adsorption process was a spontaneous endothermic process. Moreover, acidic reagents favored the desorption of Cd(II) from the Sr-HAP adsorbent, and the recycled Sr-HAP adsorbent still maintained a high adsorption capacity for Cd(II). Mechanism analysis revealed that the removal process of Cd(II) ions by the Sr-HAP adsorbent possibly involved ion exchange, co-precipitation, and surface complexation. Overall, the synthesized Sr-HAP exhibited an excellent adsorption capacity and good stability, thus acting as a promising candidate for removing Cd(II) from wastewater. • An efficient strontium-doped hydroxyapatite was synthesized for Cd(II) removal. • The Sr-HAP adsorbent had a high Cd(II) adsorption capacity. • The adsorption of Cd(II) by Sr-HAP was proved to be a monolayer chemiadsorption process. • The Sr-HAP adsorbent could maintain its high adsorption ability after regeneration. • The mechanism of Cd(II) uptake by Sr-HAP was comprehensively elucidated.

Strontium‐Doped Hydroxyapatite Promotes Osteogenic Differentiation of Bone Marrow Mesenchymal Stem Cells in Osteoporotic Rats through the CaSR‐JAK2/STAT3 Signaling Pathway

Self‐repair of critical bone defects from periodontitis, tumor resection, and trauma is difficult. Osteoporosis is an abnormal bone metabolism disease characterized by increased bone resorption, decreased bone formation, and decreased activity of bone marrow mesenchymal stem cells (BMSCs), which further inhibits the repair of bone defects. Improving the osteogenic ability of BMSCs after osteoporosis is an important step in treating osteoporotic bone defects. Hydroxyapatite (HA) with good biocompatibility is widely used in bone material research. HA and strontium‐doped hydroxyapatite (Sr‐HA) microspheres are synthesized following a hydrothermal method, and the characteristics and the ability of these microspheres are explored to promote osteogenesis. Further, the role of the calcium‐sensing receptor (CaSR) and Janus kinase 2 gene/signal transducers and activators of transcription 3 (JAK2/STAT3) signaling pathway in this process are investigated. The results show that Sr‐HA, rather than HA alone, significantly promote the osteogenic differentiation of BMSCs in vitro and bone formation in vivo. Further, the effect of promoting osteogenic differentiation is realized by activating the CaSR‐JAK2/STAT3 signaling pathway. Therefore, the study demonstrates that Sr‐HA is the better choice for restoring critical bone defects.

Strontium-doped hydroxyapatite as adsorbent effectively to remove lead ions from water.

In this study, a strontium-doped hydroxyapatite (Sr-HAP) was synthesized by the solgel method, which was used as adsorbent to remove lead ions (Pb2+) from water. The results showed that the adsorption capacities of the Sr-HAP were obviously higher than those of the HAP, the adsorption capacities of which for Pb2+ reached 651.175mg/g. The proper increasement in the dosage of adsorbent was beneficial to the removal of Pb2+ by Sr-HAP. Meanwhile Sr-HAP had a wide applicable pH range for Pb2+. And the increasement in temperature could increase the adsorption capacity of Sr-HAP for Pb2+ to a certain extent. The Langmuir model was used to fit the isotherm adsorption process of Sr-HAP to Pb2+ in water. Compared with HAP, the specific surface area of Sr-HAP has increased by 11.1%, and the pore size distribution of Sr-HAP tended to be smaller and more uniform. Hence, Sr-HAP could be used as an ideal adsorbent to remove Pb2+ in wastewater.

Strontium-Doped Hydroxyapatite as Adsorbent Effectively to Remove Lead Ions from Water

Strontium-Doped Hydroxyapatite as Adsorbent Effectively to Remove Lead Ions from Water

Strontium-Doped Hydroxyapatite as Adsorbent Effectively to Remove Lead Ions from Water

Strontium-Doped Hydroxyapatite as Adsorbent Effectively to Remove Lead Ions from Water

Facile synthesis of mesoporous strontium doped hydroxyapatite microspheres for drug-delivery applications

Spherical particles with hierarchically mesoporous structure have attracted considerable attention due to their potential applications for drug/cell delivery systems. In this study, strontium-doped hydroxyapatite (Sr-HA) microspheres with mesoporous structures were successfully fabricated by a facile solid-state reaction and subsequent hydrothermal treatment. The prepared Sr-HA microspheres possessed good drug-carrying capacity and slow-release performance. Moreover, in vitro cytocompatibility was evaluated using HUVEC cells via CCK-8 assay and Live/Dead staining, revealing good cytocompatibility of the microspheres. Therefore, the prepared Sr-HA microspheres might provide an effective way to deliver a steady supply of therapeutic ions and drugs for promoting bone repair and regeneration.

3D-bulk to nanoforms of modified hydroxyapatite: Characterization and osteogenic potency in an in vitro 3D bone model system.

Synthetic bioceramics are replacing conventional methods of treating bone defects with autografts owing to the high demand of bone substitutes, with their Surface topography and size contributing to favor cytocompatibility in tissue regeneration. This experimental study deals with the comparative evaluation of the physical characterizations of four different in-house synthesized bioceramics from 3D-bulk to nanoforms of hydroxyapatite (HA), Biphasic calcium phosphate (BCP), Strontium doped hydroxyapatite (SrHA) and Silica coated hydroxyapatite (HASi) and also simultaneously evaluates adhesion, proliferation and osteogenic differentiation of rabbit adipose derived mesenchymal stem cells (RADMSCs) on these biomimetic ceramic niches. The osteogenic induced cells grown on 3D scaffolds for a period of 7, 14, 21, and 28 days were analyzed for their viability (MTT, LDH, live-dead assays), morphology (SEM), proliferation (Cytox-Red) and osteogenic differentiation (ALP, osteocalcin expression). Cellular activities and differentiation of RADMSCs were significantly higher on SrHA indicating the role of strontium in the differentiation of mesenchymal stem cells on this ceramic platform to the bone lineage. In order to reinforce the materials for hard tissue implantation and drug delivery, nano-SrHA (nSrHA) became the nanoparticle of choice based on its non-toxicity, cytocompatibility and osteogenic properties (nSrHA > nHASi > nBCP > nHA).