Conventional instruments for cancer diagnosis including magnetic resonance imaging, computed tomography scan, are expensive and require long-waiting time, whilst the outcomes have not approached to the successful early-stage diagnosis yet. Due to the special properties of graphene-based nanocomposites, e.g., good electrical and thermal conductivity, luminescence, and mechanic flexibility, these ultra-thin two-dimensional nanostructures have been extensively used as platforms for detecting biomolecules and cells. Herein, we discuss the development of two types of graphene and graphene oxide-based biosensors: electrochemical and optical, aimed for tumor detection and early diagnosis of cancer. Moreover, we highlight the challenges of their use as biosensors for cancer detection. Efficient surface modification and suitable bio-conjugation of graphene and graphene oxide is discussed, including key role in improvement of the biocompatibility, and improved performance in terms of selectivity and sensitivity towards the early diagnosis of cancer.

中文翻译：

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使用石墨烯和氧化石墨烯进行早期癌症诊断的电化学和光学生物传感器。


传统的癌症诊断仪器包括磁共振成像、计算机断层扫描等，价格昂贵且等待时间长，而且结果尚未达到成功的早期诊断。由于石墨烯基纳米复合材料的特殊性能，例如良好的导电性和导热性、发光性和机械灵活性，这些超薄二维纳米结构已被广泛用作检测生物分子和细胞的平台。在这里，我们讨论了两种类型的基于石墨烯和氧化石墨烯的生物传感器的开发：电化学和光学，旨在肿瘤检测和癌症的早期诊断。此外，我们强调了将它们用作癌症检测生物传感器的挑战。讨论了石墨烯和氧化石墨烯的有效表面改性和合适的生物共轭，包括在改善生物相容性方面的关键作用，以及提高癌症早期诊断的选择性和灵敏度方面的性能。