The detection of intact cells in their original state is of great importance for early diagnosis of disease. In this work, we report the detection of living K562 chronic myeloid leukemia cells using an innovative label-free hybrid graphene/gold nanopyramid based surface-enhanced Raman scattering (SERS) trough grid method. The position of the cells can be well controlled by the trough grid so that they can remain unchanged in the liquid at room temperature for up to 2 h. The graphene sheet permits SERS hot spot identification and provides a chemical enhancement for the biological constituents. Different states of K562 cells were thus detected. Two types of SERS signals of K562 cells can be clearly distinguished using principal component analysis (PCA), corresponding to two different states of the K562 cell, namely, the living state and dead state. And their SERS signal ratio severely varies as a function of the storage time. PCA analysis shows that, within 2 h after taking K562 cells out of the incubator, living cells account for more than 60% of the total cells. The SERS signal variation has been attributed to an increased number of dead cells suspended in the cell culture fluid. We demonstrate a proof-of-concept study of the clarification of the state variation, from the molecular level, of the K562 cells as a function of time using a graphene-SERS platform. This method is of great potential for leukemia diagnosis and on the development of leukemia drugs.

中文翻译：

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使用石墨烯-SERS 平台检测不同状态的 K562 白血病细胞

检测原始状态的完整细胞对于疾病的早期诊断非常重要。在这项工作中，我们报告了使用创新的无标记混合石墨烯/金纳米锥体的表面增强拉曼散射 (SERS) 槽网格方法检测活的 K562 慢性髓性白血病细胞。槽式网格可以很好地控制细胞的位置，使其在室温下在液体中保持不变长达 2 小时。石墨烯片允许 SERS 热点识别并为生物成分提供化学增强。因此检测到 K562 细胞的不同状态。使用主成分分析（PCA）可以清楚地区分K562细胞的两种SERS信号，对应K562细胞的两种不同状态，即活态和死态。并且它们的 SERS 信号比作为存储时间的函数而严重变化。PCA分析表明，将K562细胞从培养箱中取出后2小时内，活细胞占总细胞的60%以上。SERS 信号变化归因于悬浮在细胞培养液中的死细胞数量增加。我们展示了使用石墨烯-SERS 平台从分子水平阐明 K562 细胞作为时间函数的状态变化的概念验证研究。该方法在白血病诊断和白血病药物开发方面具有巨大潜力。SERS 信号变化归因于悬浮在细胞培养液中的死细胞数量增加。我们展示了使用石墨烯-SERS 平台从分子水平阐明 K562 细胞作为时间函数的状态变化的概念验证研究。该方法在白血病诊断和白血病药物开发方面具有巨大潜力。SERS 信号变化归因于悬浮在细胞培养液中的死细胞数量增加。我们展示了使用石墨烯-SERS 平台从分子水平阐明 K562 细胞作为时间函数的状态变化的概念验证研究。该方法在白血病诊断和白血病药物开发方面具有巨大潜力。