Fe3O4/bioactive glass nanostructure: a promising therapeutic platform for osteosarcoma treatment.

An effective strategy of hyperthermia-chemotherapy-regeneration for bone-related cancer treatment is presented. For this purpose, a new approach of magnetic particles (MPs) encapsulated in bioactive glass (BG) structure, with anti-cancer activity, is evaluated. MPs are initially synthesized using a co-precipitation method and then embedded into BG structure through a sol-gel synthesis process. Results confirmed the formation of a crystalline and pure MP structure. MP-BG particles were found to be bioactive by forming a hydroxyapatite layer on their surface. The hyperthermia application of a MP-BG system was also studied. It was found that the particles reach a temperature of 42 °C in an alternating magnetic field. Doxorubicin (DOX), a widely used anticancer drug, was loaded in MP-BG. To enhance the loading efficiency, the BG was surface modified to create NH2groups on the surface. The encapsulation and release of DOX was studied over 48 h.In vitrotests were performed using human osteosarcoma cell line (MG63). The results demonstrated the non-cytotoxic nature of MP and MP-BG tested at various concentrations. DOX release from MP-BG resulted in decreased MG63 viability. Also, fluorescence microscopy visualization confirmed the intracellular uptake of MP-BG particles and the release of DOX. These results indicate that our suggested strategy of combined hyperthermia-chemotherapy-regeneration using MP-BG structure represents a powerful approach in cancer treatment and tissue regeneration.

The role of graphene oxide interlayer on corrosion barrier and bioactive properties of electrophoretically deposited ZrO2-10 at. % SiO2 composite coating on 316 L stainless steel.

In order to overcome the poor adhesion of zirconia-silica coating electrophoretically deposited on 316 L stainless steel, graphene oxide (GO) was used as an interlayer. The effect of this interlayer on morphological, microstructural, corrosion performance and bioactivity behavior of ZrO2-10 at. % SiO2 coating was studied. The zirconia-silica coating with the GO interlayer revealed a higher barrier performance as a more compact and a greater adhesive layer to the substrate was created. Indeed, the GO interlayer led to an improvement in apatite formation on zirconia-silica coating surface probably due to create higher roughness. Briefly, the GO interlayer was effective on enhancement of electrochemical performance and biological property of zirconia-silica composite coating, making it a suitable candidate for biomaterials applications.

Mesoporous bioactive glasses for the combined application of osteosarcoma treatment and bone regeneration.

In this study, mesoporous bioactive glass (MBG) sub-micro particles were prepared through sol-gel synthesis and possessed a uniform and spherical structure with particle size of 302 ±â€¯43 nm, a pore size of 4 nm and a high surface area of 354 m2 g-1. Alendronate (AL) is often used for the treatment of bone associated diseases, in particular osteosarcoma. However, due to the low bioavailability and high toxicity at increased doses, local and sustained release would be an ideal approach to AL delivery. Here, MBGs and aminated MBGs (AMBG) were applied as carriers for AL loading. High encapsulation efficiency of 75% and 85% and loading efficiency of 60% and 63%, for MBG and AMBG, respectively, was achieved. The release profile of AL from AMBG showed a better sustained and controlled release mechanism compared to MBG. In vitro results demonstrated the non-cytotoxic nature of both MBG and AMBG following exposure to MG63 osteoblast like cell line. AL release from MBG and AMBG, even at lower concentration, provoked decreased MG63 proliferation. The osteogenic potential of MBG and AMBG following exposure to dental pulp stem cells was evaluated using alizarin red assay.

Mesoporous and hollow hydroxyapatite nanostructured particles as a drug delivery vehicle for the local release of ibuprofen.

The high risk of infection caused by implantation of orthopedic bio-metals is still a daunting challenge for surgeons as it can lead to implant failure. One approach to overcome this issue is the local release of antibacterial drug through coating on the surface of a metallic implant. One ideal carrier for this purpose is hydroxyapatite (HA) particles which are bioactive, biodegradable, biocompatible and have the potential to bond to bone. In the current study, highly crystalline mesoporous HA nanostructure particles were successfully synthesized in a low-temperature solvent process with the aid of an inorganic CaCO3 template and then fully characterized. The specific surface area and the average size of the cavities of the nanostructured mesoporous HA particles were 85 m2/g and 20 nm, respectively. The feasibility of the prepared HA mesoporous nanostructures for drug delivery, using ibuprofen as a model drug, was also investigated. The as-prepared HA mesoporous nanostructures showed a high drug-loading capacity, as well as sustained drug release in a phosphate buffered saline (PBS) at a pH of 7.4. Overall, results show that HA mesoporous nanostructures gave great potential in bone regeneration and local delivery of either drugs or biomolecules.