A new multifunctional nanoparticle to perform a near-infrared (NIR)-responsive remote control drug release behavior was designed for applications in the biomedical field. Different from the previous studies in formation of Fe3O4-Au core-shell nanoparticles resulting in a spherical morphology, the heterostructure with polyhedral core and shell was presented with the truncated octahedral Fe3O4 nanoparticle as the core over a layer of trisoctahedral Au shell. The strategy of Fe3O4@polymer@Au was adopted using poly-l-lysine as the mediate layer, followed by the subsequent seeded growth of Au nanoparticles to form a Au trisoctahedral shell. Fe3O4@Au trisoctahedra possess high-index facets of {441}. To combine photothermal and chemotherapy in a remote-control manner, the trisoctahedral core-shell Fe3O4@Au nanoparticles were further covered with a mesoporous silica shell, yielding Fe3O4@Au@mSiO2. The bondable oligonucleotides (referred as dsDNA) were used as pore blockers of the mesoporous silica shell that allowed the controlled release, resulting in a NIR-responsive DNA-gated Fe3O4@Au@mSiO2 nanocarrier. Taking advantage of the magnetism, remotely triggered drug release was facilitated by magnetic attraction accompanied by the introduction of NIR radiation. DNA-gated Fe3O4@Au@mSiO2 serves as a drug control and release carrier that features functions of magnetic target, MRI diagnosis, and combination therapy through the manipulation of a magnet and a NIR laser. The results verified the significant therapeutic effects on tumors with the assistance of combination therapy consisting of magnetic guidance and remote NIR control.

Taking advantage of the character of Au nanorods (NRs) to absorb NIR light, a NIR-responsive oligonucleotide-gated ensemble is developed to perform intracellular drug delivery. Using an oligonucleotide bio-gate enables siRNA release into cells for translational regulation as well as cytotoxicity in anti-cancer drug delivery.

This study investigated the effect of fixation screw number of intramedullary nail on the postoperative stability of the femoral construct in treatment of periprosthetic fractures after total knee arthroplasty. With use of a material testing machine, both compressive and torsion tests were conducted to evaluate the biomechanical behavior of intact, and femora with periprosthetic fractures treated with retrograde intramedullary nail with 5-screw and 9-screw fixations. The results indicated the followings: 1) the average compressive stiffness for intact, 5-screw and 9-screw groups were 1,159±61.7, 950.6±18.6 and 958.2±26.1 N/mm, respectively. No statistical difference was found between 5-screw and 9-screw groups (p>0.05). However, significant difference was found between intact/5-screw and intact/9-screw groups (p<0.05). 2). the average torsion stiffness for intact, 5-screw group and 9-screw group were 5,527±71.2, 2,652±35.4 and 2,858±81.7 N*mm/Degree, respectively. Statistical difference was found between each other groups (p<0.05).