Background. The dental pulp is a heterogeneous soft tissue that supplies nutrients and acts as a biosensor to identify pathogenic stimuli. Regeneration of the dental pulp is one of the desirable topics for researchers. Graphene oxide nanosheets (nGOs) help overexpression of the genes related to odontogenic differentiation of stem cells from dental pulps and increases attachment and proliferation of dental pulp stem cells. Despite its benefits, nGO may be considered as a threat to the environment and human health. Therefore, the purpose of this study was to evaluate the biocompatibility potential of graphene oxide (nGO), chitosan functionalized graphene oxide (nGO-CS), and carboxylated graphene (nGO-COOH) when exposed to human dental pulp stem cells (hDPSCs). Material and Methods. Some different aspects of biocompatibility of nGO, nGO-CS, and nGO-COOH were synthesized, and several intracellular effects induced by different concentrations of graphene-based nanosheets, including cell viability, intracellular oxidative damages, and various factors such as LDH, GSH, SOD, MDA, and MMP, were studied on hDPSCs. Results. According to results, IC₅₀ was determined as 232.01, 467.81, and ≥1000 μg/mL for nGO, nGO-CS, and nGO-COOH, respectively. These results demonstrated the lower toxicity and higher cytocompatibility of nGO-CS and nGO-COOH compared to nGO. nGO-COOH not only has any adverse effect on the cell membrane and mitochondrial activity but also shows slight antioxidant activity at some concentrations. Conclusion. The findings help design safe and cytocompatible nGO derivatives for biomedical applications in dental fields.

中文翻译：

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氧化石墨烯纳米片的功能化可以减少其对牙髓干细胞的细胞毒性

背景。牙髓是一种异质的软组织，可提供营养并用作识别病原刺激的生物传感器。牙髓的再生是研究人员理想的主题之一。氧化石墨烯纳米片（nGOs）有助于与牙髓干细胞的牙源性分化相关的基因的过表达，并增加牙髓干细胞的附着和增殖。尽管非政府组织有其好处，但可以将其视为对环境和人类健康的威胁。因此，本研究的目的是评估暴露于人牙髓干细胞（hDPSCs）的氧化石墨烯（nGO），壳聚糖功能化氧化石墨烯（nGO-CS）和羧化石墨烯（nGO-COOH）的生物相容性潜力。材料与方法。合成了nGO，nGO-CS和nGO-COOH的生物相容性的一些不同方面，以及由不同浓度的石墨烯基纳米片诱导的几种细胞内效应，包括细胞活力，细胞内氧化损伤以及各种因素，如LDH，GSH，在hDPSC上研究了SOD，MDA和MMP。结果。根据结果，IC ₅₀确定为232.01，467.81，和≥1000  μ克/ mL的非政府组织，非政府组织-CS，和非政府组织-COOH，分别。这些结果证明与nGO相比，nGO-CS和nGO-COOH具有更低的毒性和更高的细胞相容性。nGO-COOH不仅对细胞膜和线粒体活性有任何不利影响，而且在某些浓度下还显示出轻微的抗氧化活性。结论。这些发现有助于设计安全且具有细胞相容性的nGO衍生物，用于牙科领域的生物医学应用。