Table A1.
A short summary of relevant articles studying the electrothermal effect, useful for new researchers in this field as a guide to what has been done and those who are working in the field.
| Article | Application | Achievement | Specific Observations |
|---|---|---|---|
| [71] | Mixing | Experimental study of illumination-induced electrothermal | The direction of force at high frequencies is form hot regions to cold regions while at low frequencies the opposite is true. |
| [14,61] | Mixing | Increasing the binding rate and significantly decreasing the incubation time to minutes | Binding rate increased by a factor of nine compared to diffusion-limited reaction |
| [4] | Pumping | Study of pumping for two electrode configurations of planar asymmetric and orthogonal | Orthogonal configuration yields higher velocities |
| [13] | Particle manipulation and pumping | Manipulation of particles and fluids of high conductivity at low voltages using a parallel plate and a planar asymmetric electrode configuration | Velocity of 162 µm·s−1 |
| [93] | Pumping | Numerical and experimental investigation of flow reversal in orthogonal electrodes | Change of flow patterns is a result of change from alternating current electrothermal (ACET) effects to alternating current electroosmosis (ACEO) phenomenon |
| [6] | Pumping | Applying asymmetry in electric potentials in conjunction with spatial asymmetry | Velocity of 2500 µm·s−1 |
| [62] | Mixing | Introducing meandering electrode configuration with electrothermal effect in a Y-shaped channel | Fivefold reduction of the mixing time of high salt content fluids compared to diffusion-limited methods |
| [97,85] | Pumping | Introducing microgrooved electrode configuration | Five times increase in pumping rate compared to conventional planar configurations |
| [69] | Pumping | Introducing two-phase AC signal configuration | 25–50% faster flow rates in two-phase configuration compared to the conventional single-phase configuration |
| [60] | Mixing | Introducing concentric electrode design | Velocity of 70 µm·s−1 |
| [11] | Mixing | Using asymmetric electrodes for immunoassay | Ten times acceleration in binding rate compared to diffusion-limited method (30 min vs. 3 min) |
| [1] | Pumping | Thermally biased ACET pumping using symmetric and asymmetric electrodes | Velocity of 750 µm·s−1 |
| [75] | Particle manipulation | Using parallel plate (opposing) electrodes in conjunction with thin film resistive heaters | Sorting between 1 µm and 2 µm particles |
| [92] | Pumping | Study on the effect of the number of electrode pairs over channel length; asymmetric planar electrodes | Increasing the number of electrode pairs helps increase the pumping efficiency |
| [105] | Pumping | Introducing electrodes both on top and bottom of the microchannel; asymmetric planar electrodes | Opposing electrodes increase the flow rate by 105% |
| [76] | Pumping | Multiple Array Electrothermal Micropump (MAET) with different actuation patterns and cross sections | Flow rate of 16 × 106 µm3·s−1 |
| [96] | Pumping | 3D circular electrodes | Flow rate of 15 × 106 µm3·s−1 |
| [104] | Mixing and pumping | Numerical investigation of simultaneous pumping and mixing by introducing microelectrodes on side walls of the microchannel | Mixing efficiency of 80% in ˂3 min and over a length of ˂600 µm |
| [135] | Pumping | Numerical study of multiple array ACET channel | Flow rate of 16 × 106 µm3·s−1 |
| [74,108] | Pumping | Study of using thin film heaters for pumping | 2.5 times faster flow rate with thin film heaters compared to Joule heating alone |
| [63] | Pumping | Application of ACET pumping to cell culture on chip | Flow rate of 44.82 µL·h−1 |
| [139] | Particle manipulation | Combining ACET and dielectrophoresis (DEP) for detection of circulating cell-free DNA (cfDNA) | Detection of cfDNA in 10 min in concentrations as low as 43 ng·mL−1 |
| [140] | Pumping | Numerical and experimental study of the effects of conductivity and channel height on ACET flow | A critical conductivity exists below which there is no net flow and there exists only microvortices |
| [119] | Mixing | Quantum dot-linked immunodiagnostic assay coupled with ACET mixing | Reduction of detection time from 3.5 h to 30 min using a volume of 2 µL |
| [59] | Particle manipulation | Development of a mathematical model for rapid electrokinetic patterning (REP) REP based on ACET and DEP | Increasing particle size results in an increase in ratio of ACET to DEP velocity and therefore results in a lower focusing performance |
| [73] | Mixing | Experimental study of light actuated ACET flow | When AC frequency is above liquid charge relaxation frequency, natural convection is above 35% of the ET flow. |
| [123] | Mixing | Numerical and experimental comparison of immunoassay performance when using symmetric or asymmetric electrodes | Symmetric and asymmetric geometries render different performance efficiencies only at high electric fields |
| [102] | Particle manipulation | Numerical and experimental study of electrode material in REP | Titanium electrodes are more efficient than conventionally used indium tin oxide (ITO) electrodes |
| [141] | Mixing | Numerical and experimental study of AC biased concentric electrodes in biosensors | Faster sensing speed compared to diffusion-limited conditions |
| [142] | Mixing | Numerical and experimental study of rotating asymmetric electrode pair; Supplying controlled drug concentration to tumor cells | Mixing efficiency 89.12% |
| [70] | Mixing | Numerical and experimental study of long-range fluid motion induced by ACET microvortices | Centimeter scale ACET vortices are observed |
| [124] | Mixing | Numerical study of the effect of temperature on binding efficiency in immunoassays | Keeping external surfaces of the microchannel at a constant temperature improves the binding efficiency |
| [143] | Mixing | Numerical and experimental-3D electrodes embedded inside walls of the channel | Mixing efficiency of 90% |
| [113] | Pumping | Numerical and experimental study of bi-directional micropump using asymmetric planar electrodes | 1500 µm·s−1 fluid velocity |
| [121] | Mixing | Numerical study of electrothermal effect in immunoassays | Placement of electrodes on the same wall as the reaction surface renders the best performance of the biosensor |
| [126] | Mixing | Study of pulsed ACET flow for detection of dilute samples of small molecules | 83% mixing efficiency over a length of 400 µm |
| [125] | Mixing | Numerical investigation of amplitude modulated (AM) sinewave | 100% mixing efficiency with maximum 5.5 K temperature rise |
| [144] | Mixing | Numerical investigation of the effect of ionic strength on mixing | Mixing efficiency 90% |
| [134] | Pumping | Experimental study of an immunoassay chip featuring an ACET micropump | Reducing incubation time to 1 min vs. hours in conventional methods |
| [99] | Simultaneous pumping and mixing | Numerical study of high throughput mixing using opposing asymmetric microgrooved electrodes and symmetric electrode pair | Mixing efficiency of 97.25% |
| [114] | Simultaneous pumping and mixing | Numerical study of bi-directional pumping and mixing by switching electric potential on planar electrodes | Mixing efficiency of 90% Pumping velocity 90 µm·s−1 |
| [90] | pumping | Numerical investigation of pumping non-Newtonian blood flow | Velocity of 0.02 m·s−1 |
| [89] | Mixing | Numerical investigation of the effect of shear dependent viscosity on mixing efficiency and flow rate using opposing asymmetric microgrooved electrodes and symmetric electrode pair | In similar configurations, dilatant fluids show better mixing efficiency compared to pseudoplastic fluids |
| [101] | Mixing | Study of arc electrodes in ring-shaped microchamber | 100% mixing efficiency at 8 V |
| [127] | Trapping | Using ACET and DEP to preconcentrate and detect E. Coli | Method can detect concentrations two orders of magnitude smaller than what is possible with diffusion limited methods |
| [133] | Pumping | Using laser etching on ITO glass to pattern electrodes for pumping cell culture medium in a 3D biomimetic liver lobule model | 2 µm·s−1 at 5.5 V |
| [100] | Pumping | Using castellated electrodes; combined DEP and ACET EHD for bioparticle delivery | Negative DEP prevents particles from colliding with channel surfaces; castellated electrodes eliminate ACET vortices |
| [138] | Pumping | Combining ACET and negative DEP for long range cell transport and suspension in high conductivity medium | DEP is essential for cell suspension under ACET effect |
| [95] | Simultaneous pumping and mixing | Numerical investigation of 3D asymmetric spiral microelectrode pair | Flow rate 440 µm·s−1 |
| [91] | Pumping | Numerical investigation of the effect of electrode configuration on pumping mechanism of non-Newtonian blood flow | Ring shaped electrodes are the optimal configuration for blood flow pumping |
| [88] | Pumping, mixing, and trapping | Study of 3D particle-fluid flow under simultaneous effects of ACET, thermal buoyancy (TB), and DEP using multi-layered electrodes | Long range vortices induced by ACET and short-range circulations induced by TB |
| [77] | Simultaneous pumping and mixing | Introducing two opposing microelectrode arrays placed at an angle relative to channel length | Mixing time reduced by 95% compared to diffusion-limited methods |
| [72] | Mixing | Study of light induced ACET flow over electrodes of different materials using opposing electrodes | Electrodes with high optical absorption rate and low thermal conductivity are best for effective light-induced heating |
| [58] | Comprehensive particle and droplet manipulation | Combining ACET and DEP | Particle transit time between multiple branches 0.008 s; droplet sorting purity 90%; particle sorting purity 93% |