Institute of Functional Nano & Soft Materials (FUNSOM), Collaborative Innovation Center of Suzhou, Nano Science and Technology, Soochow University, Suzhou, Jiangsu, 215123, China.
Small. 2014 Apr 24;10(8):1544-54. doi: 10.1002/smll.201303234. Epub 2013 Dec 21.
With the increasing interests of using graphene and its derivatives in the area of biomedicine, the systematic evaluation of their potential risks and impacts to biological systems is becoming critically important. In this work, we carefully study how surface coatings affect the cytotoxicity and extracellular biodegradation behaviors of graphene oxide (GO) and its derivatives. Although naked GO could induce significant toxicity to macrophages, coating those two-dimensional nanomaterials with biocompatible macromolecules such as polyethylene glycol (PEG) or bovine serum albumin (BSA) could greatly attenuate their toxicity, as independently evidenced by several different assay approaches. On the other hand, although GO can be gradually degraded through enzyme induced oxidization by horseradish peroxidase (HRP), both PEG and BSA coated GO or reduced GO (RGO) are rather resistant to HRP-induced biodegradation. In order to obtain biocompatible functionalized GO that can still undergo enzymatic degradation, we conjugate PEG to GO via a cleavable disulfide bond, obtaining GO-SS-PEG with negligible toxicity and considerable degradability, promising for further biomedical applications.
随着人们对石墨烯及其衍生物在生物医学领域应用的兴趣日益增加，对其潜在风险和对生物系统影响的系统评估变得至关重要。在这项工作中，我们仔细研究了表面涂层如何影响氧化石墨烯（GO）及其衍生物的细胞毒性和细胞外生物降解行为。尽管裸露的 GO 会对巨噬细胞产生显著的毒性，但将这些二维纳米材料用生物相容性大分子如聚乙二醇（PEG）或牛血清白蛋白（BSA）进行涂层处理，可以大大降低其毒性，这一点已被几种不同的检测方法独立证实。另一方面，尽管 GO 可以通过辣根过氧化物酶（HRP）诱导的酶促氧化逐渐降解，但 PEG 和 BSA 涂层的 GO 或还原氧化石墨烯（RGO）对 HRP 诱导的生物降解都具有很强的抵抗力。为了获得仍能进行酶促降解的生物相容的功能化 GO，我们通过可断裂的二硫键将 PEG 连接到 GO 上，得到具有低毒性和相当降解性的 GO-SS-PEG，有望进一步应用于生物医学领域。
