[论文解读] Biocompatibility of Pristine Graphene Monolayers, Nanosheets and Thin Films

Jennifer Conroy, Navin Kumar Verma+5 more|arXiv (Cornell University)|Jun 10, 2014

Graphene and Nanomaterials Applications参考文献 2被引用 11

一句话总结

本研究采用人肺上皮A549细胞评估了纯化石墨烯单层、纳米片和薄膜的生物相容性。通过多模态检测方法，研究显示其细胞毒性极低，无显著形态学变化，且活性氧生成量低，表明尽管碳黑对照组毒性更高，石墨烯仍是一种极具潜力的生物相容性材料，适用于生物医学和电子应用。

ABSTRACT

There is an increasing interest to develop nanoscale biocompatible graphene structures due to their desirable physicochemical properties, unlimited application opportunities and scalable production. Here we report the preparation, characterization and biocompatibility assessment of novel graphene flakes and their enabled thin films suitable for a wide range of biomedical and electronic applications. Graphene flakes were synthesized by a chemical vapour deposition method or a liquid-phase exfoliation procedure and then thin films were prepared by transferring graphene onto glass coverslips. Raman spectroscopy and transmission electron microscopy confirmed a predominantly monolayer and a high crystalline quality formation of graphene. The biocompatibility assessment of graphene thin films and graphene flakes was performed using cultured human lung epithelial cell line A549 employing a multimodal approach incorporating automated imaging, high content screening, real-time impedance sensing in combination with biochemical assays. No detectable changes in the cellular morphology or attachment of A549 cells growing on graphene thin films or cells exposed to graphene flakes (0.1 to 5 ug/mL) for 4 to 72 h was observed. Graphene treatments caused a very low level of increase in cellular production of reactive oxygen species in A549 cells, but no detectable damage to the nuclei such as changes in morphology, condensation or fragmentation was observed. In contrast, carbon black proved to be significantly more toxic than the graphene. These data open up a promising view of using graphene enabled composites for a diverse scope of safer applications.

研究动机与目标

• 评估纯化石墨烯在不同形态（单层、纳米片和薄膜）下的生物相容性，以探索其在生物医学和电子应用中的潜力。
• 将石墨烯的细胞毒性效应与一种已知有毒的碳质材料——碳黑进行比较。
• 采用多模态方法结合成像、阻抗传感和生化检测，评估细胞反应。
• 确定石墨烯暴露是否在人肺上皮细胞中诱导氧化应激或核损伤。

提出的方法

• 通过化学气相沉积法和液相剥离法合成石墨烯纳米片。
• 将石墨烯转移至玻璃盖玻片上，制备用于细胞培养研究的薄膜。
• 利用拉曼光谱和透射电子显微镜对石墨烯进行表征，确认其为单层且结晶质量高。
• 使用A549人肺上皮细胞暴露于石墨烯纳米片（0.1–5 µg/mL）4–72小时，进行生物相容性评估。
• 采用自动化成像、高内涵筛选、实时阻抗传感和生化检测，评估细胞形态、活力和氧化应激水平。
• 以碳黑作为阳性对照，用于比较毒性水平。

实验结果

研究问题

• RQ1 纯化石墨烯以单层、纳米片或薄膜形式是否会在人肺上皮A549细胞中诱导细胞毒性？
• RQ2 石墨烯暴露对A549细胞的细胞形态、黏附性和活力随时间如何变化？
• RQ3 A549细胞在石墨烯暴露后，活性氧生成水平如何？
• RQ4 石墨烯是否会在A549细胞中引起可检测的核损伤，如染色质浓缩或断裂？
• RQ5 在相同细胞模型中，石墨烯的毒性与碳黑相比如何？

主要发现

• 在石墨烯薄膜上培养或暴露于石墨烯纳米片（0.1–5 µg/mL）4–72小时后，A549细胞未观察到细胞形态或黏附性的可检测变化。
• 石墨烯暴露仅引起A549细胞中活性氧生成量极低程度的增加，表明氧化应激极小。
• 石墨烯暴露后，A549细胞未观察到可检测的核损伤，包括形态改变、染色质浓缩或断裂。
• 碳黑的毒性显著高于石墨烯，凸显了在本模型中石墨烯的优越生物相容性。
• 拉曼光谱和透射电子显微镜证实了主要为单层、高结晶度石墨烯结构的形成。
• 多模态评估方法成功在多个生物学终点上证明了石墨烯的安全性。