Spatial Manipulation and Assembly of Nanoparticles by Atomic Force Microscopy Tip-Induced Dielectrophoresis

Abstract

In this article, we present a novel method of spatial manipulation and assembly of nanoparticles via atomic force microscopy tip-induced dielectrophoresis (AFM-DEP). This method combines the high-accuracy positioning of AFM with the parallel manipulation of DEP. A spatially nonuniform electric field is induced by applying an alternating current (AC) voltage between the conductive AFM probe and an indium tin oxide glass substrate. The AFM probe acted as a movable DEP tweezer for nanomanipulation and assembly of nanoparticles. The mechanism of AFM-DEP was analyzed by numerical simulation. The effects of solution depth, gap distance, AC voltage, solution concentration, and duration time were experimentally studied and optimized. Arrays of 200 nm polystyrene nanoparticles were assembled into various nanostructures, including lines, ellipsoids, and arrays of dots. The sizes and shapes of the assembled structures were controllable. It was thus demonstrated that AFM-DEP is a flexible and powerful tool for nanomanipulation.

A review of polystyrene bead manipulation by dielectrophoresis

“…6D. 151 Both the size and shape of the assembled structures were controllable by various experimental parameters; this demonstrated the potential of AFM-DEP for applications in the fabrication of nanostructures and arrays, assembly of nanodevices, and non-destructive manipulation of biological nanoparticles. Recently, a coaxial AFM nano-probe device has been studied for DEP trapping of DNA molecules in Tris-EDTA and PBS buffers.…”

Modeling and Analysis of the Two-Dimensional Axisymmetric Acoustofluidic Fields in the Probe-Type and Substrate-Type Ultrasonic Micro/Nano Manipulation Systems

“…For the PM, the right-hand side of Equation 10is included as a source term by adding a so-called weak contribution to the governing equations, and Equation 12acts as a body force term. For the RSM, Equations (20) and (21) act as the body force terms in the r and z directions, respectively. More detailed descriptions of the FEM models will be shown in Section 3.…”

“…For simulating the acoustofluidic field by the RSM, since the driving force components (Equations (20) and (21)) contain nonlinear terms, the variation of the driving force for acoustic streaming may be drastic within the fluid domain near the MMP. Therefore, to precisely compute the driving force for acoustic streaming in the whole fluid domain as much as possible, based on the computation capability of the laptop (Lenovo E51-80-ISE, i7-6500U CPU, 16G RAM), the maximum element size of the fluid domain near the MMP is set to be 10 µm (about 0.34% of the wavelength of acoustic field at 40 kHz) in 0 < r < 0.5 mm region (Region 1), where removal of micro/nanoscale particles occurs.…”

“…In the past two decades, acoustic micro/nano manipulation methods [1][2][3] have shown tremendous potential applications in biomedical engineering [4,5], bioanalytical chemistry [6,7], material science [8,9], micro/nano fabrication [10,11], lab-on-a-chip (LOC) technology [12,13] and so forth. Compared to other physical micro/nano manipulation methods, such as optical methods [14,15], magnetic methods [16][17][18], mechanical methods [19,20], and dielectrophoretic (DEP) methods [21][22][23], acoustic micro/nano manipulation methods possess the merits such as simple fabrication, little selectivity to optical/electrical/magnetic properties of manipulated samples, and good compatibility with other LOC components [1,2]. The acoustic micro/nano manipulation devices can be divided into two major categories, i.e., surface acoustic wave (SAW)-based devices [24,25] and bulk acoustic wave (BAW)-based devices [1].…”

Determination of Dielectric Properties of Cells using AC Electrokinetic-based Microfluidic Platform: A Review of Recent Advances

“…Although this isotonic solution has no negative effect on the application of AC electrokinetic-based microfluidics in bio-related fields, it may impede the integration of this mechanism with other fashionable micro/nano-robotic manipulation tools-such as AFM [107][108][109], scanning ion conductance microscopy [110][111][112], and acoustic tweezers [113][114][115]-to rapidly and simultaneously acquire the intrinsic properties of cells. The integration of DEP with AFM was demonstrated to be capable of manipulating and assembling nanoparticles accurately [116][117][118]. However, to the best of our knowledge, no published studies have provided convincing evidence for the feasibility of this integration.…”