Fabrication of Polymer Microfluidics: An Overview

Abstract

Microfluidic platform technology has presented a new strategy to detect and analyze analytes and biological entities thanks to its reduced dimensions, which results in lower reagent consumption, fast reaction, multiplex, simplified procedure, and high portability. In addition, various forces, such as hydrodynamic force, electrokinetic force, and acoustic force, become available to manipulate particles to be focused and aligned, sorted, trapped, patterned, etc. To fabricate microfluidic chips, silicon was the first to be used as a substrate material because its processing is highly correlated to semiconductor fabrication techniques. Nevertheless, other materials, such as glass, polymers, ceramics, and metals, were also adopted during the emergence of microfluidics. Among numerous applications of microfluidics, where repeated short-time monitoring and one-time usage at an affordable price is required, polymer microfluidics has stood out to fulfill demand by making good use of its variety in material properties and processing techniques. In this paper, the primary fabrication techniques for polymer microfluidics were reviewed and classified into two categories, e.g., mold-based and non-mold-based approaches. For the mold-based approaches, micro-embossing, micro-injection molding, and casting were discussed. As for the non-mold-based approaches, CNC micromachining, laser micromachining, and 3D printing were discussed. This review provides researchers and the general audience with an overview of the fabrication techniques of polymer microfluidic devices, which could serve as a reference when one embarks on studies in this field and deals with polymer microfluidics.

Microfluidic Devices: A Tool for Nanoparticle Synthesis and Performance Evaluation

“…Polymeric materials were introduced due to their great flexibility and low cost in the production of microfluidics devices. 62 Elastomers are the most employed polymers in this area. Some examples are polydimethylsiloxane (PDMS), thermoset polyester (TPE), and thermoplastic polymers (e.g., polystyrene, polycarbonate, poly(methyl methacrylate), polyethylene glycol diacrylate, and polyurethane).…”

“…Advantageously, technological advances occurred over the years, and advanced materials, including polymer substrates, paper, or composites, were used for microfluidic chip production. Polymeric materials were introduced due to their great flexibility and low cost in the production of microfluidics devices . Elastomers are the most employed polymers in this area.…”

Droplets microfluidics platform—A tool for single cell research

“…In the past few decades, droplet microfluidics technology has developed rapidly, and it has been used in the design of microreactors because of its strong controllability in performing various operations ( Chen et al, 2022 ; Jobdeedamrong et al, 2023 ). Due to their compatibility with many chemical and biological reagents, droplet microfluidic systems have been used to prepare complex reactants and special materials, such as polymer particles ( Juang and Chiu, 2022 ), microgel particles ( Rojek et al, 2022 ), and nanoparticles ( Küçüktürkmen et al, 2022 ; Maged et al, 2022 ; Niculescu et al, 2022 ). Moreover, droplet microfluidics is widely used in biomedical research due to their simple and easy operation and high-throughput encapsulation capability.…”

Manufactured tissue-to-tissue barrier chip for modeling the human blood–brain barrier and regulation of cellular trafficking

“…The micro-patterned pillar array supported Matrigel filling without leakage into side channels while pushing out the culture medium. However, it is hard to construct micro-scale pillar arrays in injectionmolded plastic chip due to its limited resolution and design restrictions (e.g., non-uniform thickness, undercuts, and air bubble trapping in the mold cavities 34,35 ). Thus, injection molded MPS is limited to a simple channel structure.…”