Microfluidic-assisted fiber production: Potentials, limitations, and prospects

Abstract

Besides the conventional fiber production methods, microfluidics has emerged as a promising approach for the engineered spinning of fibrous materials and offers excellent potential for fiber manufacturing in a controlled and straightforward manner. This method facilitates low-speed prototype synthesis of fibers for diverse applications while providing superior control over reaction conditions, efficient use of precursor solutions, reagent mixing, and process parameters. This article reviews recent advances in microfluidic technology for the fabrication of fibrous materials with different morphologies and a variety of properties aimed at various applications. First, the basic principles, as well as the latest developments and achievements of microfluidic-based techniques for fiber production, are introduced. Specifically, microfluidic platforms made of glass, polymers, and/or metals, including but not limited to microfluidic chips, capillary-based devices, and three-dimensional printed devices are summarized. Then, fiber production from various materials, such as alginate, gelatin, silk, collagen, and chitosan, using different microfluidic platforms with a broad range of cross-linking agents and mechanisms is described. Therefore, microfluidic spun fibers with diverse diameters ranging from submicrometer scales to hundreds of micrometers and structures, such as cylindrical, hollow, grooved, flat, core–shell, heterogeneous, helical, and peapod-like morphologies, with tunable sizes and mechanical properties are discussed in detail. Subsequently, the practical applications of microfluidic spun fibers are highlighted in sensors for biomedical or optical purposes, scaffolds for culture or encapsulation of cells in tissue engineering, and drug delivery. Finally, different limitations and challenges of the current microfluidic technologies, as well as the future perspectives and concluding remarks, are presented.

Droplets microfluidics platform—A tool for single cell research

“…The fluorescence-based binding assay described also applies to detecting secretory molecules, such as cytokines and growth factors, in the presence of fluorescently labeled ligands ( Sesen and Whyte, 2020 ). In addition, the method can also be adapted for high-throughput enzyme screening and directed evolution or for screening antibodies and other molecules that inhibit enzyme activity by using fluorescent substrates or other fluorescence analysis ( Reymond et al, 2009 ; Abrishamkar et al, 2022 ; Yuan et al, 2022 ). Colin et al (2015) used a microdroplet system to screen out new hydrolases from macroscopic genomic sources.…”

Recent Advances in MXene-Based Fibers, Yarns, and Fabrics for Wearable Energy Storage Devices Applications

“…The curing strategy includes photopolymerization, chemical cross-linking, ion cross-linking, and solvent evaporation. A variety of curing strategies make it possible to choose more raw materials for the preparation of fibers. , For example, Wu et al . used the MXene/CNTs mixture as the core flow and MgSO 4 as the solidified sheath flow to manufacture graded fibers (Figure f).…”

“…A variety of curing strategies make it possible to choose more raw materials for the preparation of fibers. 121,122 For example, Wu et al 125 used the MXene/CNTs mixture as the core flow and MgSO 4 as the solidified sheath flow to manufacture graded fibers (Figure 4f). The MXene/CNTs mixture dispersion is further condensed by Mg 2+ ions through microchannels and then dried to form fibers.…”

“…It is energy saving, safe, and easy to operate. The “Y” microchannel device can realize the preparation of core–sheath fibers by core flow and sheath flow. − In the microchannel of microfluidic spinning technology, it is necessary to solidify into a specific shape through a certain reaction precursor solution. The curing strategy includes photopolymerization, chemical cross-linking, ion cross-linking, and solvent evaporation.…”

Microfluidic Fabrication of Highly Efficient Hydrogel Optical Fibers for In Vivo Fiber‐Optic Applications

“…Their dimension, shape, and structure are dictated by the shape and arrangement of the microcapillary, providing various geometries, including singlefibril, hollow-tube, and double-walled fibers. [18][19][20][21][22][23] The multichannel devices used in this study are designed to assemble with three or four coaxially aligned capillaries, allowing the formation of hydrogel optical fibers with a single-or dual-core structure, respectively. Dual-core hydrogel optical fibers can simultaneously realize the dual delivery of lights of different wavelengths.…”