Durso M, Borrachero-Conejo A I, Bettini C, Treossi E, Scidà A, Saracino E, Gazzano M, Christian M, Morandi V, Tuci G, Giambastiani G, Ottaviano L, Perrozzi F, Benfenati V, Melucci M, Palermo V
Consiglio Nazionale delle Ricerche, Istituto per la Sintesi Organica e la Fotoreattività (CNR-ISOF), via Piero Gobetti 101, 40129 Bologna, Italy.
J Mater Chem B. 2018 Sep 7;6(33):5335-5342. doi: 10.1039/c8tb01410h. Epub 2018 Jul 25.
Graphene and graphene substrates display huge potential as material interfaces for devices and biomedical tools targeting the modulation or recovery of brain functionality. However, to be considered reliable neural interfaces, graphene-derived substrates should properly interact with astrocytes, favoring their growth and avoiding adverse gliotic reactions. Indeed, astrocytes are the most abundant cells in the human brain and they have a crucial physiological role to maintain its homeostasis and modulate synaptic transmission. In this work, we describe a new strategy based on the chemical modification of graphene oxide (GO) with a synthetic phospholipid (PL) to improve interaction of GO with brain astroglial cells. The PL moieties were grafted on GO sheets through polymeric brushes obtained by atom-transfer radical-polymerization (ATRP) between acryloyl-modified PL and GO nanosheets modified with a bromide initiator. The adhesion of primary rat cortical astrocytes on GO-PL substrates increased by about three times with respect to that on glass substrates coated with standard adhesion agents (i.e. poly-d-lysine, PDL) as well as with respect to that on non-functionalized GO. Moreover, we show that astrocytes seeded on GO-PL did not display significant gliotic reactivity, indicating that the material interface did not cause a detrimental inflammatory reaction when interacting with astroglial cells. Our results indicate that the reported biomimetic approach could be applied to neural prosthesis to improve cell colonization and avoid glial scar formation in brain implants. Additionally, improved adhesion could be extremely relevant in devices targeting neural cell sensing/modulation of physiological activity.
石墨烯及其衬底作为针对大脑功能调节或恢复的设备及生物医学工具的材料界面，展现出了巨大潜力。然而，要成为可靠的神经界面，源自石墨烯的衬底应与星形胶质细胞进行适当的相互作用，促进其生长并避免不良的胶质增生反应。事实上，星形胶质细胞是人类大脑中数量最多的细胞，它们在维持大脑内环境稳定和调节突触传递方面具有关键的生理作用。在这项工作中，我们描述了一种基于用合成磷脂（PL）对氧化石墨烯（GO）进行化学修饰的新策略，以改善GO与脑星形胶质细胞的相互作用。通过丙烯酰基修饰的PL与用溴化物引发剂修饰的GO纳米片之间的原子转移自由基聚合（ATRP）获得的聚合物刷，将PL部分接枝到GO片上。原代大鼠皮质星形胶质细胞在GO-PL衬底上的粘附相对于涂有标准粘附剂（即聚-d-赖氨酸，PDL）的玻璃衬底以及未功能化的GO上的粘附增加了约三倍。此外，我们表明接种在GO-PL上的星形胶质细胞没有显示出明显的胶质增生反应性，这表明该材料界面在与星形胶质细胞相互作用时不会引起有害的炎症反应。我们的结果表明，所报道的仿生方法可应用于神经假体，以改善细胞定植并避免脑植入物中形成胶质瘢痕。此外，改善的粘附在针对神经细胞生理活动传感/调节的设备中可能极其重要。
