Biocompatibility of PEDOT:DNA and PPy:DNA for Bioelectronics

Poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) has showed promising potential for soft and implantable bioelectronics due to mixed ionic-electronic transport¹. On the other hand, natural biopolymers and their composites with synthetic conductive polymers have attracted researchers for biomedical applications due to their biocompatibility, biodegradability, and low toxicity nature². They can be utilized for a variety of applications, including drug delivery, tissue engineering, and medical implants and grafts³. Although biomaterial properties of polypyrrole (PPy) and PEDOT have been extensively studied for implantable electrodes, introducing acidic the surfactants, such as PSS might be cons to this approach. The long-term effects of PSS in the brain have not yet been fully investigated.<br/><br/>The aim of the present study is to investigate cytotoxicity of PEDOT:PSS as well as the new composite materials previously suggested for bioelectronics by our group.⁴ Deoxyribonucleic acid (DNA) was extracted from salmon fish residuals and implemented as secondary dopant during the template synthesis of biocomposites. PEDOT:DNA and PPy:DNA were synthesized by following the same procedure.⁴ As a follow up study, we performed a comprehensive set of cytotoxicity testing of PEDOT:PSS, PEDOT:DNA and PPy:DNA films using NIH3T3 mouse fibroblast cell line. The thin-films of the materials were deposited on glass and used as specimen which allowed cells to grow and proliferate on the surface. The cross-linker glycidoxypropyltrimethoxysilane (GOPS) was added into the dispersed solution of composites against film delamination. We monitored the morphological changes via fluorescence microcopy. The live/dead cytotoxicity/viability tests were determined by flow cytometry. The results show that the novel composites are promising with high biocompatibility to living cells while preserving the benefits of electrical conduction for future biomedical applications. Overall, the implementation of natural polymers in biocomposites for medicine has the potential to revolutionize the field by providing safer, more effective treatments for a range of medical conditions.<br/><br/><br/>References<br/>[1] D.T. Simon, E.O. Gabrielsson, K. Tybrandt, M. Berggren, Chem. Rev. 116, 21, 13009–13041 (2016).<br/>[2] S. Lee, S.M. Silva, L.M.C. Aguilar, T. Eom, S.E. Moulton, B.S. Shim, J. Mater. Chem. B, 10, 8575 (2022)<br/>[3] C. Wang, T. Yokota, T Someya, <i>Chem. </i><i>Rev.</i> 121, 4, 2109–2146 (2021).<br/>[4] S. Tekoglu, D. Wielend, M. C. Scharber, N. S. Sariciftci, C. Yumusak, Adv. Mat. Tech. 1900699, (2020).