Bakouei Mostafa, Abdorahimzadeh Seyedamirhosein, Taghipoor Mojtaba
Micro Nano System Laboratory (MNSL), Department of Mechanical Engineering, Sharif University of Technology, Tehran, Iran.
Phys Chem Chem Phys. 2020 Nov 21;22(43):25306-25314. doi: 10.1039/d0cp04728g. Epub 2020 Nov 3.
Resistive pulse sensing (RPS) has proved to be a viable method for the detection and characterization of micro and nano particles. Modern fabrication methods have introduced different nanopore geometries for resistive pulse sensors. In this paper, we have numerically studied the effects of membrane thickness and the pore's cone angle, as the main geometrical parameters, on the sensing performance of the nanopores used for nanoparticle detection in the resistive pulse sensing method. To compare the sensing performance, three resistive pulse quality parameters were investigated - sensitivity, pulse duration and pulse amplitude. The thorough investigation on the relations between the geometrical parameters and the pulse quality parameters produced several interesting results, which were categorized and summarized for different nanopore structures (as different nanopore platforms) enabling the readers to more effectively compare them with one another. The results revealed that large cone angle and low aspect ratio nanopores have higher pulse amplitude and sensitivity, but their low duration could be a challenge in the process of detecting the resistive pulse. In addition, our results show small variation in sensitivity and duration of large cone angle nanopores with respect to pore length change, which is explained using the effective length concept and the definition of electric field strength and length. The findings of the present work can be used in practical applications where choosing the optimal pore geometry is of crucial significance. Furthermore, the results provide several possible ways to improve the resistive pulse quality for better sensing performance.
电阻脉冲传感（RPS）已被证明是一种用于检测和表征微米和纳米颗粒的可行方法。现代制造方法为电阻脉冲传感器引入了不同的纳米孔几何形状。在本文中，我们通过数值研究了作为主要几何参数的膜厚度和孔的锥角对电阻脉冲传感方法中用于纳米颗粒检测的纳米孔传感性能的影响。为了比较传感性能，研究了三个电阻脉冲质量参数——灵敏度、脉冲持续时间和脉冲幅度。对几何参数与脉冲质量参数之间关系的深入研究产生了几个有趣的结果，这些结果针对不同的纳米孔结构（作为不同的纳米孔平台）进行了分类和总结，使读者能够更有效地相互比较。结果表明，大锥角和低纵横比的纳米孔具有更高的脉冲幅度和灵敏度，但它们较短的持续时间可能是检测电阻脉冲过程中的一个挑战。此外，我们的结果表明，大锥角纳米孔的灵敏度和持续时间随孔长度变化的差异较小，这可以用有效长度概念以及电场强度和长度的定义来解释。本工作的研究结果可用于实际应用中，在这些应用中选择最佳的孔几何形状至关重要。此外，这些结果提供了几种可能的方法来改善电阻脉冲质量以获得更好的传感性能。
