title: Diamond-Graphite Nanoplatelet Surfaces as Conductive Substrates for the Electrical Stimulation of Cell Functions.
abstract: The nanocarbon allotropes constitute valid alternatives when designing control and actuation devices for electrically assisted tissue regeneration purposes, gathering among them important characteristics such as chemical inertness, biocompatibility, extreme mechanical properties, and, importantly, low and tailorable electrical resistivity. In this work, coatings of thin (100 nm) vertically aligned nanoplatelets composed of diamond (5 nm) and graphite were produced via a microwave plasma chemical vapor deposition (MPCVD) technique and used as substrates for electrical stimulation of MC3T3-E1 preosteoblasts. Increasing the amount of N2up to 14.5 vol % during growth lowers the coatings' electrical resistivity by over 1 order of magnitude, triggers the nanoplatelet vertical growth, and leads to the higher crystalline quality of the nanographite phase. When preosteoblasts were cultured on these substrates and subjected to two consecutive daily cycles of 3 μA direct current stimulation, enhanced cell proliferation and metabolism were observed accompanied by high cell viability. Furthermore, in the absence of DC stimulation, alkaline phosphatase (ALP) activity is increased significantly, denoting an up-regulating effect of preosteoblastic maturation intrinsically exerted by the nanoplatelet substrates.
authors.affiliation: i3N and Physics Department, University of Aveiro , 3810-193 Aveiro, Portugal.
authors.forename: N F
authors.identifier: http://orcid.org/0000-0001-9685-7479
authors.initials: NF
authors.lastname: Santos
authors.affiliation: TEMA-NRG, Mechanical Engineering Department and CICECO-Aveiro Institute of Materials, Department of Chemistry, University of Aveiro , 3810-193 Aveiro, Portugal.
authors.forename: M
authors.initials: M
authors.lastname: Cicuéndez
authors.affiliation: i3N and Physics Department, University of Aveiro , 3810-193 Aveiro, Portugal.
authors.forename: T
authors.initials: T
authors.lastname: Holz
authors.affiliation: CESAM, Biology Department, University of Aveiro , 3810-193 Aveiro, Portugal.
authors.forename: V S
authors.initials: VS
authors.lastname: Silva
authors.affiliation: i3N and Physics Department, University of Aveiro , 3810-193 Aveiro, Portugal.
authors.forename: A J S
authors.initials: AJ
authors.lastname: Fernandes
authors.affiliation: TEMA-NRG, Mechanical Engineering Department, University of Aveiro , 3810-193 Aveiro, Portugal.
authors.forename: M
authors.initials: M
authors.lastname: Vila
authors.affiliation: i3N and Physics Department, University of Aveiro , 3810-193 Aveiro, Portugal.
authors.forename: F M
authors.initials: FM
authors.lastname: Costa
mesh_terms: D049109:Cell Proliferation; D002470:Cell Survival; D018130:Diamond; D004558:Electric Stimulation; D006108:Graphite; D049329:Nanostructures
chemical_list: D018130:Diamond; D006108:Graphite
keywords: biocompatibility; differentiation; electrical stimulation; nanocarbon hybrids; preosteoblasts; proliferation