The project was divided into three work packages.
WP 1. Electroactive porous scaffold development. The first step has therefore been the establishment of the 3D matrices. The 3D substrates mimicking bone tissue were developed using the conjugated conducting polymer poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) and a matrix polymer, determining the mechanical properties of the scaffold. The polymer used to tune the mechanical properties of the scaffolds was collagen Type 1. This polymer was selected because it represents the biological component of bones. Collagen Type 1, indeed, represents the master used by cells to deposit Hydroxyapatite, the mineral counterpart. Blends of the two polymers were prepared and characterized for their mechanical and electrical properties.
Human adipose derived stem cells and Neural crest derived stem cells were used to assess both scaffolds cytocompatibility and their ability to influence stem cells differentiation.
WP 2. OECT fabrication and 3D scaffolds integration. Organic electrochemical transistors were developed targeting BMP-2, an earlier marker of differentiation. A protocol was established to functionalize the electrodes and a thorough characterization was performed to assess each functionalization step. Electrical characterization of the devices was performed to assess devices response to the specific analyte.
WP 3. Monitoring stem cells differentiation upon electrical stimulation with the developed OECT.
In collaboration with Prof Sarah Cartmell, from the University of Manchester capactive coupling experiments were performed in order to evaluate the effect on stem cells differentiation. A protocol was defined involving a bioreactor, previously developed in Prof Cartmell laboratories, the electroactive scaffolds and human adipose derived stem cells. The developed OECTs were tested to evaluate their ability to detect BMP-2 from a real sample.
As a result of the research activities of the fellow a number of publications are in preparation or have already been accepted for publication, as reported t=in the list below.
Publications:
1. Iandolo, D., Pitsalidis, C, Santoro, F., Cui, B., Widera, D., Owens, R. M., Collagen-enriched 3D electroactive scaffolds for human stem cells growth and osteogenic differentiation. Manuscript in preparation.
2. Pitsalidis, C., Pappa, A.M. Moysidou, C.M. Iandolo, D. and Owens, R. M. “Conducting and Conjugated Polymers for Biosensing Applications” book chapter in the Fourth Edition of the Handbook of Conducting Polymers, publisher CRC Press/Taylor & Francis (accepted for publication).
3. Iandolo, D., Pennacchio, F. A., Mollo, V., Rossi, D., Dannhauser, D., Cui, B., Owens, M. R., Santoro, F.. Electron microscopy for 3D scaffolds-cell biointerface characterization. Adv. Biosys. 2018, 1800103.
4. Pitsalidis, C., Ferro M., Iandolo, D., Tzounis, L., Inal, S., Owens, R. M. Transistor in a tube: a route to three-dimensional bioelectronics. Science Advances, 2018.
5. Owens, M.R. Iandolo, D., Wittmann, K., A (bio) materials approach to three-dimensional cell biology. MRS Communications, 2017, 7, 287–288.
