Jean-Charles ARNAULT
CEA, LIST, Diamond Sensors Laboratory
https://scholar.google.fr/citations...
Vendredi 25 mail à 14h (salle Magat) :
“Properties of hydrogenated nanodiamonds”
Résumé
After an overview of the research topics currently investigated at Diamond Sensors Laboratory, this seminar will focus on our activities concerning diamond nanoparticles (nanodiamonds or NDs). NDs behave physical and chemical properties expected from bulk diamond like their biocompatibility and their versatile surface chemistry based on carbon. Moreover, the high surface to volume ratio of nanodiamonds can be tuned with sizes down to 5 nm depending on their synthesis methods [1]. This nanoscale confers new properties to NDs, often governed by their surface chemistry. For bioapplications, this small primary size could ensure a better elimination for in vivo studies [2]. The presence of color centers (NV, SiV) hosted by diamond lattice allow to use fluorescent nanodiamonds as biomarkers [3].
After presenting the synthesis and the current applications of nanodiamonds, this seminar will focus on the intrinsic properties of hydrogenated detonation NDs, from their surface chemistry to the colloidal behavior in water suspensions. Two hydrogenation methods will be compared in terms of hydrogen grafted or incorporated into NDs via isotope studies (3H) [4]. The hydrogenated NDs revealed an ability to produce reactive oxygen species (ROS) in radioresistant human cancer cells under gamma irradiation. This radiosensitive behavior was in vitro demonstrated, turning these cells into senescence state [5]. The physical and chemical mechanisms involved in the production of radicals were investigated by illuminating aqueous colloids of hydrogenated nanodiamonds under X-rays or gamma-rays in collaboration with Cécile Sicard-Roselli and Emilie Brun. An overproduction of hydroxyl radicals and solvated electrons versus water radiolysis was measured using the 7-OH-coumarin as a fluorescent probe [6]. These results well evidence that NDs can act as active nanoparticles under illumination.
References
[1] O. A. Shenderova, N. Nunn, Production and purification of nanodiamonds in : Nanodiamonds Advanced Material Analysis, Properties and Applications, J. C. Arnault Ed. (Elsevier (2017) pp 25-56.
[2] K. Turcheniuk and V. N. Mochalin, Biomedical applications of nanodiamond, Nanotechnology 28 (2017) 252001.
[3] Y. Y. Hui, L. J. Su, O. Y. Chen, Y. T. Chen, T. M. Liu, H. C. Chang, Wide-field imaging and flow cytometric analysis of cancer cells in blood by fluorescent nanodiamond labeling and time gating, Scientific Reports 4 (2014) 5574.
[4] H.A. Girard, A. El Kharbachi, S. Garcia-Argote, T. Petit, P. Bergonzo, B. Rousseau, J.C. Arnault, Tritium labeling of detonation nanodiamonds. Chem. Comm. 50 (2014) 2916–2918.
[5] R. Grall, H. A. Girard, L. Saad, T. Petit, C. Gesset, M. Combis-Schlumberger, V. Paget, J. Delic, J. C. Arnault, S. Chevillard, Impairing the radioresistance of cancer cells by hydrogenated Nanodiamonds, Biomaterials 61 (2015) 290-298.
[6] M. Kurzyp, H. A. Girard, Y. Cheref, E. Brun, C. Sicard-Roselli, S. Saada, J. C. Arnault, Chem. Comm., 53 (2017) 1237.
