title: Nanodiamonds on tetrahedral amorphous carbon significantly enhance dopamine detection and cell viability.
abstract: We hypothesize that by using integrated carbon nanostructures on tetrahedral amorphous carbon (ta-C), it is possible to take the performance and characteristics of these bioelectrodes to a completely new level. The integrated carbon electrodes were realized by combining nanodiamonds (NDs) with ta-C thin films coated on Ti-coated Si-substrates. NDs were functionalized with mixture of carboxyl and amine groups NDandanteor amine NDamine, carboxyl NDvoxor hydroxyl groups NDHand drop-casted or spray-coated onto substrate. By utilizing these novel structures we show that (i) the detection limit for dopamine can be improved by two orders of magnitude [from 10µM to 50nM] in comparison to ta-C thin film electrodes and (ii) the coating method significantly affects electrochemical properties of NDs and (iii) the ND coatings selectively promote cell viability. NDandanteand NDHshowed most promising electrochemical properties. The viability of human mesenchymal stem cells and osteoblastic SaOS-2 cells was increased on all ND surfaces, whereas the viability of mouse neural stem cells and rat neuroblastic cells was improved on NDandanteand NDHand reduced on NDamineand NDvox.The viability of C6 cells remained unchanged, indicating that these surfaces will not cause excess gliosis. In summary, we demonstrated here that by using functionalized NDs on ta-C thin films we can significantly improve sensitivity towards dopamine as well as selectively promote cell viability. Thus, these novel carbon nanostructures provide an interesting concept for development of various in vivo targeted sensor solutions.
authors: Department of Electrical Engineering and Automation, School of Electrical Engineering, Aalto University, PO Box 13500, Aalto 00076, Finland; Department of Chemistry, University College London, Gordon Street 20, London WC1H 0AJ, UK. Electronic address: peltola@aalto.fi.
authors: Emilia
authors: E
authors: Peltola
authors: Department of Materials Science and Engineering, School of Chemical Technology, Aalto University, PO Box 16200, Aalto 00076, Finland.
authors: Niklas
authors: N
authors: Wester
authors: Department of Chemistry, University College London, Gordon Street 20, London WC1H 0AJ, UK.
authors: Katherine B
authors: KB
authors: Holt
authors: Department of Forest Products Technology, School of Chemical Technology, Aalto University, PO Box 11000, Aalto 00076, Finland.
authors: Leena-Sisko
authors: LS
authors: Johansson
authors: Department of Materials Science and Engineering, School of Chemical Technology, Aalto University, PO Box 16200, Aalto 00076, Finland.
authors: Jari
authors: J
authors: Koskinen
authors: Carbodeon Ltd. Oy, Pakkalankuja 5, Vantaa 01510, Finland.
authors: Vesa
authors: V
authors: Myllymäki
authors: Department of Electrical Engineering and Automation, School of Electrical Engineering, Aalto University, PO Box 13500, Aalto 00076, Finland.
authors: Tomi
authors: T
authors: Laurila
mesh_terms: D000818:Animals; D015374:Biosensing Techniques / Q000379:methods*; D002244:Carbon / Q000737:chemistry*; D002460:Cell Line; D002470:Cell Survival; D004298:Dopamine / Q000032:analysis*; D055664:Electrochemical Techniques / Q000379:methods*; D004566:Electrodes; D006801:Humans; D057230:Limit of Detection; D051379:Mice; D058612:Nanodiamonds / Q000737:chemistry* / Q000648:ultrastructure; D049329:Nanostructures / Q000737:chemistry / Q000648:ultrastructure; D051381:Rats; D012825:Silicon / Q000737:chemistry; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry
chemical_list: D058612:Nanodiamonds; D002244:Carbon; D014025:Titanium; D004298:Dopamine; D012825:Silicon
keywords: Biocompatibility; Dopamine; Nanodiamonds; Tetrahedral amorphous carbon