•MBG nanospheres were synthesized by a facile sol-gel method with CTAB.•MBG nanospheres demonstrate excellent hydroxyapatite formation ability.•MBG nanospheres possess a controlled release of anti-cancer drug (DOX).•MBG nanospheres have a pH-sensitive drug release capability.•MBG nanospheres can be used as an injectable drug carrier for bone cancer.Mesoporous bioactive glass (MBG) nanospheres have been synthesized by a facile method of sacrificing template using cetyl trimethyl ammonium bromide (CTAB) as surfactant. The prepared MBG nanospheres possess high specific surface area (632 m2 g−1) as well as uniform size (∼100 nm). In addition, MBG nanospheres exhibited a quick in vitro bioactive response in simulated body fluids (SBF) and excellent bioactivity of inducing hydroxyapatite (HA) forming on the surface of MBG nanospheres. Furthermore, MBG nanospheres can sustain release of doxorubicin (DOX) with a higher encapsulation efficiency (63.6%) and show distinct degradation in PBS by releasing Si and Ca ions. The encapsulation efficiency and DOX release of MBG nanospheres could be controlled by mesoporous structure and local pH environment. The greater surface area and pore volumes of prepared MBG nanospheres are conducive to bioactive response and drug release in vitro. The amino groups in DOX can be easily protonated at acidic medium to become positively charged NH+3, which allow these drug molecules to be desorbed from the surface of MBG nanospheres via electrostatic effect. Therefore, the synthesized MBG nanospheres have a pH-sensitive drug release capability. In addition, the cytotoxicity of MBG nanospheres was assessed using a cell counting kit-8 (CCK-8), and results showed that the synthesized MBG nanospheres had no significant cytotoxicity to MC3T3 cells. These all indicated that as-prepared MBG nanospheres are promising candidates for bone tissue engineering.Schematic illustration of formation processes and potential application of MBG nanospheres.Download high-res image (164KB)Download full-size image

•Tb/MBG nanospheres were synthesized by a facile sol-gel method.•Tb/MBG nanospheres demonstrate excellent hydroxyapatite mineralization ability.•Tb/MBG nanospheres possess a sustained release of anti-cancer drug (DOX).•Tb/MBG nanospheres have positive potential for the therapy of bone cancer.Terbium (Tb) doped mesoporous bioactive glasses (Tb/MBG) nanospheres were successfully synthesized by a facile sol-gel method using cetyl trimethyl ammonium bromide (CTAB) as the template. Results indicated that Tb/MBG had spherical morphology (100–200 nm), higher specific surface area (250–350 m2/g) and narrow mesopore size distribution (2–3 nm). In order to investigate the effects of Tb on the in vitro bioactivity, prepared Tb/MBG nanospheres were soaking in simulated body fluid (SBF) for 3 days, and results indicated incorporation Tb ions in the MBG nanospheres could improve the hydroxyapatite formation ability. In addition, Tb/MBG nanospheres showed controlled release property of anti-cancer drugs (DOX) and distinct degradation in PBS with different pH values. Their release mechanism can be explained by Fickian diffusion according the Higuchi model, and the delivery of DOX from Tb/MBG nanospheres can be dominated by changing the doping concentration of Tb and the values of pH. In addition, the cytotoxicity of Tb/MBG nanospheres was assessed using a cell counting kit-8 (CCK-8), and results showed that the synthesized Tb/MBG nanospheres at low concentration had no significant cytotoxicity in MC3T3 cells. These all note that this material is a promising candidate for the therapy of bone tissue regeneration.Download high-res image (160KB)Download full-size image

Selenium (Se) incorporated mesoporous bioactive glasses (MBG) have been prepared using the traditional sol–gel method. The Se/MBG particles retain typical characteristics of mesoporous structures (SBET=230–250 m2/g and DP=4.0–4.1 nm) and excellent hydroxyapatite formation ability when soaked in simulated body fluids for 3 days. To investigate their delivery properties further, doxorubicin (DOX) was selected as a model drug. The results indicate that the Se/MBG particles exhibit sustained DOX delivery, and controlled release mechanism by Fickian diffusion according the Higuchi model. Based on a favorable in vitro bioactive response and controllable DOX delivery, this material is a promising candidate for application in malignant bone tumor therapy.

•Sm/MBG/alginate microspheres were synthesized by alginate cross-linking with Ca2 +.•Sm/MBG/alginate microspheres demonstrate apatite formation ability.•Sm/MBG/alginate microspheres possess a sustained release of anti-cancer drug (DOX).•Sm/MBG/alginate microspheres have positive potential for the therapy of bone cancer.Samarium (Sm) incorporated mesoporous bioactive glasses (MBG) microspheres have been prepared using the method of alginate cross-linking with Ca2 + ions. The in vitro bioactivities of Sm/MBG/alginate microspheres were studied by immersing in simulated body fluid (SBF) for various periods. The results indicated that the Sm/MBG/alginate microspheres have a faster apatite formation rate on the surface. To investigate their delivery properties further, doxorubicin (DOX) was selected as a model drug. The results showed that the Sm/MBG/alginate microspheres exhibit sustained DOX delivery, and their release mechanism is controlled by Fickian diffusion according the Higuchi model. In addition, the delivery of DOX from Sm/MBG/alginate microspheres can be dominated by changing the doping concentration of Sm and the values of pH microenvironment. These all revealed that this material is a promising candidate for the therapy of bone cancer.The schematic illustration of controlled DOX release from the Sm/MBG alginate microspheres.