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arXiv · 1902.01850

Reduction and simultaneous doping of graphene oxide to repel LDL in treatment of atherosclerosis disease

L. M. Rivera·A. F. Betancur·D. G. Zarate·D. Torres Torres·L. M. Hoyos·A. G. Garcia
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Abstract

Atherosclerotic disease develops when there is endothelial dysfunction, making low density lipoproteins (LDL) which are cholesterol carriers traveling in the blood, very likely to penetrate the endothelium layer triggering the formation of the atheromatous plaque and leading to the obstruction of blood vessels. For some time now, devices called stents have been used to re-open the light of the plugged artery, allowing the restoration of blood flow. However, this treatment has disadvantages like developing intra-stent restenosis and progression of the atherosclerosis, clogging the blood vessel again. For these reasons it is necessary to develop new materials and strategies focused on the prevention and correction of this pathology and its subsequent complications. In the present work, a reduction and in situ nitrogen doping method in graphene oxide (N-rGO) was studied. By means of XPS a 9.57% at of nitrogen doping was demonstrated and was found that the pyrrole type nitrogen is predominant. Due to nitrogen doping and pyrrolic sites, the N-rGO surface reached high levels of negative electric charge, which was verified by Electrostatic Force Microscopy (EFM) and wettability tests between the LDL at different oxidation levels and the synthesized N-rGO; contact angles between 95.7{\deg} and 130.4{\deg} were obtained which indicates repulsion between both materials. The N-rGO was also characterized by SEM and TEM where a wrinkled morphology typical of this type of material was observed and the hexagonal atomic arrangement of GO is distinguished. Finally, cell viability tests using 3-(4,5-dimethylthiazolyl)-2,5-diphenyltetrazolium bromide (MTT) assay were carried out on human umbilical cord endothelial cells (HUVEC) to analyze the cellular response at different concentrations of N-rGO, obtaining favorable behavior up to concentrations of 100 ({\mu}g/mL).

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L. M. Rivera, A. F. Betancur, D. G. Zarate, D. Torres Torres, L. M. Hoyos, A. G. Garcia. 2019-02-05. Reduction and simultaneous doping of graphene oxide to repel LDL in treatment of atherosclerosis disease. https://arxiv.org/abs/1902.01850

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