Nanoceramics for orthopedic applications

In the past two decades, iron oxide or superparamagnetic iron oxide nanoparticles (SPION, e.g., y-Fe Oj, FejO and associated compounds) have been actively studied for medical image, drug dehvery, and hyperthermia treatment purposes. SPION has 

Other material properties of SPION also set up new and promising scenarios for treating bone-related cancer and infection without using anticancer drugs and antibi- 

Calcium phosphate nanoparticles are also novel nonviral vectors for gene delivery [58]. Many studies have demonstrated that nanometer calcium phosphates possess higher penetration rates into cell membrane and their transfection efficiency can be up to 25-fold higher than that of conventional particles. Recently, dye-loaded calcium phosphate nanoparticles have been developed for photodynamic therapy against bacteria and cells. The strategy of photodynamic therapy utilizes biocompatible light-sensitive substances (i.e., photosensitizers) that become toxic when exposed to 

Specific lights to target and destroy malignant or diseased cells. Calcium phosphate nanoparticles have been studied as efficient carriers for the incorporation and delivery of photosensitizers (such as 5,10,15,20-tetrakis(3-hydroxyphenyl)-porphyrin) against cells (e.g synoviocyte, macrophage) and bacteria (e.g., S. aureus) [59,60]. 

However, there is both research and clinical evidence showing nanometer particles released from calcium phosphates may largely impair the abihty of BMSCs to proliferate and mature into a functional osteoblast phenotype [64]. This opposite evidence indicates that more and thorough research on utilizing stem cell and calcium phosphate nanoparticle for bone repair and regeneration is required before possible clinical applications. 

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