Understanding the functions of biomolecules at the single-molecule level is crucial due to their important and diverse roles in cell regulation. Recently, nanotweezers made of dual carbon nanoelectrodes have been developed for single-cell biopsies by applying a high alternating voltage. However, high electric voltage can induce Joule heating, water electrolysis, and other side effects on cell activity, which may be unfavorable for cellular applications. Here, we report a low-voltage nanotweezer for trapping of single DNA molecules using etching-engineered nanoelectrodes which effectively reduce the minimum trapping voltage by six times. Meanwhile, the low-voltage nanotweezer displays an improved trapping stiffness. Based on the finite element method simulations, we attribute the mechanism for the low-voltage nanotweezers to the increase in spatial heterogeneity and nonuniformity of electric field by etching of quartz near the nanoelectrodes. This work opens a new dimension for noninvasive single-molecule manipulation in solution and potential applications in single-cell biopsies.

中文翻译：

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用于捕获单分子的蚀刻工程低压介电泳纳米镊子

了解生物分子在单分子水平上的功能至关重要，因为它们在细胞调控中扮演着重要而多样的角色。最近，已开发出由双碳纳米电极制成的纳米镊子，通过施加高交流电压用于单细胞活检。然而，高电压会引起焦耳热、水电解和其他对细胞活性的副作用，这可能不利于细胞应用。在这里，我们报告了一种使用蚀刻工程纳米电极捕获单个 DNA 分子的低压纳米镊子，该电极有效地将最小捕获电压降低了六倍。同时，低压纳米镊子显示出改进的捕获刚度。基于有限元法模拟，我们将低压纳米镊子的机制归因于通过蚀刻纳米电极附近的石英增加了电场的空间异质性和不均匀性。这项工作为溶液中的无创单分子操作和单细胞活检中的潜在应用开辟了新的维度。