Repository logo

Browsing by Author "Wei, Huang"

Now showing 1 - 1 of 1
  • Piezoelectric electrospun nanomaterials as a plataform for biological applications
    Publication . Wei, Huang; Pires, Pedro Filipe Duarte Louzeiro
    Piezoelectric materials as new smart biomaterials show great potential for biological applications. Specifically, piezoelectric polyvinylidene fluoride (PVDF) electrospun nanofibers, possess outstanding properties, which provide many advantages in various healthcare applications. We followed a systematic fabrication approach to create a new device for mechanical stimulation of cells, based upon the inverse piezoelectric effect from functionalized PVDF nanofibers, and tested it with different cell lines. The major contents in this thesis are presented as follows: (1) Fibers fabrication and characterization Multi-walled carbon nanotubes (MWCNTs) were blended with PVDF to fabricate highly aligned PVDF/MWCNTs piezoelectric nanofibers. In this part we investigated the PVDF/MWCNTs nanofibers’ properties, such as, morphology, alignment, crystal structure, mechanical properties, piezoelectric output voltage and cytotoxicity. (2) Biological applications of inverse piezoelectric stimulation To explore the effect of mechanical stimulation on cellular behavior, specifically, morphology, proliferation, migration and differentiation, we selected three cell line models: NIH3T3 cells as fibroblasts; PC12 cells as neuroblastic cells; mesenchymal stem cells. All cells were submitted to an inverse piezoelectric stimulation over 30 minutes per day, with 10 V amplitude at 5 Hz frequency driving signal. It was found that inverse piezoelectric stimulation with PVDF/MWCNTs nanofibers, not just improved the proliferation of NIH3T3 cells, but also efficiently guided the cells migration. In the part of neuroblastic cells investigation, the adhesion, proliferation and differentiation results of PC12 cells submitted to the inverse piezoelectric stimulation shown a great improvement. In the study of mesenchymal stem cells (MSCs), the inverse piezoelectric PVDF/MWCNTs nanofibers could not improve the adhesion and proliferation of MSCs in early stage, but it improved the osteogenic differentiation. Therefore, according to our results, we believe that inverse piezoelectric stimulation with aligned PVDF/MWCNTs nanofibers holds a great potential on wound healing, nerves regeneration and bone tissue engineering applications.
    2021-03-24Doctoral thesis Open access Show more