| Popis: |
Compared with traditional electronic materials (metals and semiconductors), electrically conductive biopolymers have improved compatibility with biological cells and human biological tissues. This allows creating new bioelectronic devices, for example, biosensors, drug delivery devices, 3D tissue-engineering matrix et al. A new laser method has been developed for the 3D manufacturing of electrically conductive nanocomposites with a given architecture. The architecture may be similar to the microelectronic component base (for example, the creation of microchannels between nanocomposite regions for designing transistors). A pulsed ytterbium fiber laser connected to a galvanometric scanner (laser wavelength - 1064 nm, pulse duration - 100 ns, frequency - 100 kHz, irradiation power up to 10 W) was used to form nanocomposites. By the galvanometric scanner, the focused laser beam moved along the trajectory (XYZ) specified in the software. As a result, the samples had the desired geometric 3D shape. Homogeneous dispersions of carbon nanotubes and biopolymers (albumin, collagen and chitosan amino sugar) were used as raw materials on a flexible substrate. The phase transition of the liquid dispersion of nanotubes into a solid was the main mechanism for the nanocomposites formation process. With focused laser irradiation, the temperature in the region of defects in carbon nanotubes increased, in contrast to other regions of nanotubes. As a result, the nanotubes were connected in an electrically conductive scaffold. Nanocomposites had high conductivity values of ~10 S/m, as well as high hardness of 300-500 MPa. The biocompatibility of nanocomposites has been proven in vitro и in vivo. |
