Imaging the surface charge of biomolecules such as proteins and DNA, is crucial for comprehending their structure and function. Unfortunately, current methods for label-free, sensitive, and rapid imaging of the surface charge of single DNA molecules are limited. Here, we propose a plasmonic microscopy strategy that utilizes charge-sensitive single-crystal monolayer WS₂ materials to image the local charge density of a single λ-DNA molecule. Our study reveals that WS₂ is a highly sensitive charge-sensitive material that can accurately measure the local charge density of λ-DNA with high spatial resolution and sensitivity. The consistency of the surface charge density values obtained from the single-crystal monolayer WS₂ materials with theoretical simulations demonstrates the reliability of our approach. Our findings suggest that this class of materials has significant implications for the development of label-free, scanning-free, and rapid optical detection and charge imaging of biomolecules.

中文翻译：

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使用电荷敏感单层 WS2 对单个 DNA 进行等离子体成像

对蛋白质和 DNA 等生物分子的表面电荷进行成像对于理解其结构和功能至关重要。不幸的是，目前对单个 DNA 分子表面电荷进行无标记、灵敏和快速成像的方法是有限的。在这里，我们提出了一种等离子体显微镜策略，利用电荷敏感的单晶单层 WS ₂材料对单个 λ-DNA 分子的局部电荷密度进行成像。我们的研究表明，WS ₂是一种高灵敏度的电荷敏感材料，可以以高空间分辨率和灵敏度精确测量 λ-DNA 的局部电荷密度。从单晶单层WS ₂材料获得的表面电荷密度值与理论模拟的一致性证明了我们方法的可靠性。我们的研究结果表明，此类材料对于生物分子的无标记、免扫描、快速光学检测和电荷成像的开发具有重要意义。