Fixation of pharmaceuticals on graphene surfaces

在目前的一个联合项目中，申请者能够证明芳基偶氮甲酸酯适合于石墨烯的一种新的、缺陷选择性官能化。在本研究项目中，将考虑不同反应条件下的更多芳基自由基源在石墨烯功能化中的选择性。在第二部分中，新开发的官能化反应将用于将可切割连接物连接到石墨烯表面。因此，附着了荧光染料以实现结合化合物的靶向释放的模型研究。对表面结合的石墨烯和溶解的石墨烯衍生物进行了研究。最后，收集的结果将用于药物在石墨烯表面的结合，而在共价结合的情况下，可切割的连接物将实现触发释放。上述石墨烯功能化的选择性是基于各种芳基前体的使用，特别是将用于将细胞抑制药物与聚乙二醇衍生物结合到石墨烯上。这样，不仅可以改善水的溶解性和癌细胞靶向性，而且还有可能显著降低石墨烯的毒性。总而言之，石墨烯的芳基选择性官能化使得开发新型的、医学上适用的载体系统成为可能，它可以克服石墨烯作为载体材料的已知缺点。为了达到医学应用的目的，在研究项目中制备的石墨烯结合物将继续-并在最后阶段-密集地评估它们的生物医学特性。

In a current joint project, the applicants were able to show that arylazocarboxylic acid esters are suitable for a novel, defect selective functionalization of graphene. In this research project, further aryl radical sources under various reaction conditions are to be considered with regard to selectivity in graphene functionalization. In the second section, the newly developed functionalization reactions will be used to link cleavable linkers to the graphene surface. Thereby a fluorescent dye is attached to enable the model study of the targeted release of bound compounds. The studies are performed on both surface bound graphene and dissolved graphene derivatives. Finally, the collected results will be used for the binding of drugs on the graphene surface, whereat in the case of covalent binding, a triggered release will be enabled by the cleavable linkers. The above mentioned selectivity in graphene functionalization, which is based on the use of various aryl radical precursors, will in particular be employed to attach cytostatic drugs in combination with polyethylene glycol derivatives to graphene. In this way, not only water solubility and cancer cell targeting can be improved, but it is further possible to significantly reduce the otherwise observed toxicity of graphene. In summary, the aryl radical based, selective functionalization of graphene thus enables the development of novel, medicinally applicable carrier systems, which can overcome the yet known drawbacks of graphene as carrier material. To aim at medicinal application, the graphene conjugates prepared within the research project will be continuously – and in the final stage intensively –evaluated regarding their biomedical properties.