No abstract

An electrically conductive scaffold was prepared by assembling PEDOT on a chitosan/gelatin porous scaffold via in situ interfacial polymerization.

No abstract

No abstract

No abstract

No abstract

Engineering scaffolds with excellent electro-activity is increasingly important in tissue engineering and regenerative medicine. Herein, conductive poly(3,4-ethylenedioxythiophene) doped with hyaluronic acid (PEDOT-HA) nanoparticles were firstly synthesized via chemical oxidant polymerization. A three-dimensional (3D) PEDOT-HA/Cs/Gel scaffold was then developed by introducing PEDOT-HA nanoparticles into a chitosan/gelatin (Cs/Gel) matrix. HA, as a bridge, not only was used as a dopant, but also combined PEDOT into the Cs/Gel via chemical crosslinking. The PEDOT-HA/Cs/Gel scaffold was used as a conductive substrate for neural stem cell (NSC) culture in vitro. The results demonstrated that the PEDOT-HA/Cs/Gel scaffold had excellent biocompatibility for NSC proliferation and differentiation. 3D confocal fluorescence images showed cells attached on the channel surface of Cs/Gel and PEDOT-HA/Cs/Gel scaffolds with a normal neuronal morphology. Compared to the Cs/Gel scaffold, the PEDOT-HA/Cs/Gel scaffold not only promoted NSC proliferation with up-regulated expression of Ki67, but also enhanced NSC differentiation into neurons and astrocytes with up-regulated expression of β tubulin-III and GFAP, respectively. It is expected that this electro-active and bio-active PEDOT-HA/Cs/Gel scaffold will be used as a conductive platform to regulate NSC behavior for neural tissue engineering.

For hyperthermia to be used under clinical conditions for cancer therapeutics the temperature regulation needs to be precise and accurately controllable. In the case of the metal nanoparticles used for such activities, a high coercivity is a prerequisite in order to couple more energy in a single heating cycle for efficient and faster differential heating. The chemically stable Co-Zn ferrite nanoparticles have typically not been used in such self-regulating hyperthermia temperature applications to date due to their low Curie temperature usually accompanied by a poor coercivity. The latter physical property limitation under clinically applied magnetic field conditions (frequency: 100 kHz, intensity: 200 Oe) restricts the transfer of a reasonable heat energy, and thus limits the hyperthermia efficiency. Here, we report a novel Cr substituted Co-Zn ferrite (ZnCoCrFeO), whose Curie temperature and coercivity values are 45.7 °C and 174 Oe, respectively. Under clinically acceptable magnetic field conditions, the temperature of these nanoparticle suspensions can be self-regulated to 44.0 °C and, most importantly with a specific absorption rate (SAR) of 774 W kg, which is two-fold higher than the SAR standard for magnetic nanoparticles used in hyperthermia (300 W kg). The evaluation of the in vitro cytotoxicity of the nanoparticles reports a low toxicity, which points to a novel set of magnetic nanoparticles for use in self-regulating hyperthermia.