Electrowetting-on-Dielectric Based Economical Digital Microfluidic Chip on Flexible Substrate by Inkjet Printing

Abstract

In order to get rid of the dependence on expensive photolithography technology and related facilities, an economic and simple design and fabrication technology for digital microfluidics (DMF) is proposed. The electrodes pattern was generated by inkjet printing nanosilver conductive ink on the flexible Polyethylene terephthalate (PET) substrate with a 3D circuit board printer, food wrap film was attached to the electrode array to act as the dielectric layer and Teflon® AF was sprayed to form a hydrophobic layer. The PET substrate and food wrap film are low cost and accessible to general users. The proposed flexible DMF chips can be reused for a long time by replacing the dielectric film coated with hydrophobic layer. The resolution and conductivity of silver traces and the contact angle and velocity of the droplets were evaluated to demonstrate that the proposed technology is comparable to the traditional DMF fabrication process. As far as the rapid prototyping of DMF is concerned, this technology has shown very attractive advantages in many aspects, such as fabrication cost, fabrication time, material selection and mass production capacity, without sacrificing the performance of DMF. The flexible DMF chips have successfully implemented basic droplet operations on a square and hexagon electrode array.

Breaking the clean room barrier: exploring low-cost alternatives for microfluidic devices

“…It is important to note that i3DP has two main types: powder-based and photopolymer-based. In powder-based i3Dp, a polymeric sticking solution is used to agglomerate powder particles, while the photopolymer-based i3Dp deposits small droplets of both the build and support materials in a layer-by-layer process to fabricate an object ( Padash et al, 2020 ; Wang & Chen, 2020 ; Prabhakar et al, 2021 ).…”

Research progress of electrode shapes in EWOD-based digital microfluidics

“…33 lms have emerged as cost-effective alternatives for dielectric layers, signicantly reducing the overall expense of the DMF chip fabrication process. 34 The driving electrode is a pivotal component of the DMF chip as it enables the crucial droplet manipulation functionality. The effective operation of the DMF chip relies on the precise control of droplets on the electrodes.…”

“…33 Additionally, food packaging films have emerged as cost-effective alternatives for dielectric layers, significantly reducing the overall expense of the DMF chip fabrication process. 34…”

Application of Micro/Nanoporous Fluoropolymers with Reduced Bioadhesion in Digital Microfluidics

“…Therefore, the top coatings in EWOD are required to be hydrophobic materials, i.e., materials possessing static water contact angles (CAs) above 90 • . DMF setups for droplet actuation can further be divided into open setups, where the droplet is on top of the dielectric [15][16][17][18][19][20], and closed setups, where a second hydrophobized layer covers the droplet from the top [21][22][23][24][25][26]. Open setups have the advantage of simple fabrication [27] and offer less surface area for biofouling.…”