3D Printing and the characterization of an electrically conductive, alginate di-aldehyde-gelatin and polystyrene sulfonate doped polypyrrole (ADA-GEL-PPy:PSS) composite hydrogel for tissue engineering applicationsTuesday (18.06.2019) 20:07 - 20:08
Functional biomaterials promise to add an additional level of control on biomaterials’ performance in-vitro and inside the human body, being thus highly attractive for tissue engineering applications. Electrically conductive polymers, as one class of functional materials, are applicable for electrical stimulation and potential monitoring of physiological response and function. In the current study, we present the 3D printing and characterisation of an electrically conductive hydrogel composite based on oxidized alginate, alginate di-aldehyde, gelatin (ADA-GEL) and electrically conductive polystyrene sulfonate (PSS) doped polypyrrole (PPy:PSS). Pyrrole and PSS were added to ADA-GEL hydrogel precursor solutions and homogenized, followed by 3D bioplotting. The influence of monomer and PSS addition on the printability of the hydrogel precursors compared to pristine ADA-GEL hydrogel was assessed qualitatively and by rheological analyses. After 3D printing, hydrogels were crosslinked ionically. Further, pyrrole was oxidized using FeCl3 to form polypyrrole inside the hydrogel matrix to produce in-situ polymerized ADA-GEL-PPy:PSS conductive hydrogels. The gels were assessed towards their chemical composition, microstructure, electrical properties and in-vitro biocompatibility. The results indicate that it is possible to form a conductive polypyrrole:PSS structure inside ADA-GEL hydrogels. The gels showed an increased conductivity compared to ADA-GEL in wet and dry state, confirming the synthesis of electrically functional hydrogels. With the current hydrogel system, further investigations towards their application in cell stimulation setups will be performed. The gels exhibit promising properties for tissue engineering applications, and they represent thus a new and genuinely functional biomaterial class.