The Response of HeLa Cells to Fluorescent NanoDiamond Uptake
Department of Biomedical Engineering, University of Groningen, 9713 AV Groningen, The Netherlands
Author to whom correspondence should be addressed.
Sensors 2018, 18(2), 355; https://doi.org/10.3390/s18020355
Received: 11 December 2017 / Revised: 11 January 2018 / Accepted: 15 January 2018 / Published: 26 January 2018
(This article belongs to the Special Issue Sensors Based on Quantum Phenomena)
Fluorescent nanodiamonds are promising probes for nanoscale magnetic resonance measurements. Their physical properties predict them to have particularly useful applications in intracellular analysis. Before using them in intracellular experiments however, it should be clear whether diamond particles influence cell biology. While cytotoxicity has already been ruled out in previous studies, we consider the non-fatal influence of fluorescent nanodiamonds on the formation of reactive oxygen species (an important stress indicator and potential target for intracellular sensing) for the first time. We investigated the influence of different sizes, shapes and concentrations of nanodiamonds on the genetic and protein level involved in oxidative stress-related pathways of the HeLa cell, an important model cell line in research. The changes in viability of the cells and the difference in intracellular levels of free radicals, after diamond uptake, are surprisingly small. At lower diamond concentrations, the cellular metabolism cannot be distinguished from that of untreated cells. This research supports the claims of non-toxicity and includes less obvious non-fatal responses. Finally, we give a handhold concerning the diamond concentration and size to use for non-toxic, intracellular measurements in favour of (cancer) research in HeLa cells.