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 N up 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.

Electrical stimulation as a novel tool for regulating cell behavior in tissue engineering

“…Within the ES intensity range the cell proliferation rate increases with increasing intensity [95]. Preosteoblasts [123], obsteoblasts [37], unrestricted somatic human stem cells [124], human umbilical vein ECs [125], NSCs [126], human dermal fibroblasts [127] exhibited 0.2 to 1.5 times proliferation, with increasing cellular metabolic activity, and do not affect cell phenotype [123]. High-intensity ES of > 100 V/cm is also favorable for cell proliferation in a short period (< 1 ms) single stimulation, but excessively high intensity leads to cell death [128].…”

3D Fabrication with Integration Molding of a Graphene Oxide/Polycaprolactone Nanoscaffold for Neurite Regeneration and Angiogenesis

“…Conductive scaffolds have better electrical conductivity, biocompatibility and lipophilicity for cell adhesion . Among them, graphene is an extremely important nanomaterial due to its exceptional physical and chemical properties . Moreover, graphene can interact with biomolecules such as proteins, polypeptides and nucleic acids in regenerative medicine .…”

Mediation of cellular osteogenic differentiation through daily stimulation time based on polypyrrole planar electrodes

“…Santos et al . 23 used two consecutive daily cycles of 3 μA direct current stimulation on diamond-graphite nanoplatelet to enhance cell proliferation and ALP activity.…”