The spontaneously generated electrical charge of a droplet dispensed from conventional pipetting is undesirable and unpredictable for most experiments that use pipetting. Hence, a method for controlling and removing the electrical charge needs to be developed. In this study, by using the electrode-deposited pipet tip (E-pipet tip), the charge-controlling system is newly developed and the electrical charge of a droplet is precisely controlled. The effect of electrolyte concentration and volume of the transferred solution to the electrical charge of a dispensed droplet is theoretically and experimentally investigated by using the equivalent capacitor model. Furthermore, a proof-of-concept example of the self-alignment and self-assembly of sequentially dispensed multiple droplets is demonstrated as one of the potential applications. Given that the electrical charge of the various aqueous droplets can be precisely and simply controlled, the fabricated E-pipet tip can be broadly utilized not only as a general charge-controlling platform of aqueous droplets but also as a powerful tool to explore fundamental scientific research regarding electrical charge of a droplet, such as the surface oscillation and evaporation of charged droplets.

中文翻译：

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电场辅助移液对液滴自发感应电荷的电容控制。

从常规移液中散发的液滴的自发产生的电荷对于使用移液的大多数实验是不希望的，并且是不可预测的。因此，需要开发一种用于控制和去除电荷的方法。在这项研究中，通过使用电极沉积的移液器吸头（E-移液器吸头），电荷控制系统得到了新的发展，液滴的电荷得到了精确控制。通过使用等效电容器模型，从理论上和实验上研究了电解质浓度和转移溶液的体积对所分配液滴的电荷的影响。此外，作为潜在应用之一，证明了依次分配的多个液滴的自对准和自组装的概念验证示例。