One‐Step Generation of Porous GelMA Microgels by Droplet‐Based Chaotic Advection Effect

Abstract

Porous GelMA microgels are promising scaffolds for biomedical research and regenerative medicine due to their special topology, cell‐loading capacity, and high biocompatibility. However, the traditional preparation of porous microgels is often limited by some complex postprocessing processes such as freeze‐drying and swelling equilibrium. Herein, we present a simple strategy for in situ generation of porous GelMA microgels as cell carriers by integrating the placeholder of polyethylene oxide (PEO) and chaotic advection effect of droplets in microfluidic devices. The device is mainly composed of four functional units, including droplet generation, rapid mixing, photopolymerization, and collection. The strategy allows precise control of the size and porosity of the microgels by changing the flow rates of the continuous and dispersed phases. Furthermore, both human mesenchymal stem cells (hMSCs) and umbilical vein endothelial cells (HUVECs) cultured on the surface of obtained microgels show high cell viability, spreading, and proliferation, which indicate their good biocompatibility and potential as microcarriers for various cell types. The proposed strategy provides a novel approach for the preparation of porous microgels holding promise in tissue engineering and scalable cell expansion.

Spontaneous Formation of Uniform Cell‐Sized Microgels through Water/Water Phase Separation

“…Microgels have a wide variety of properties and applications depending on their size and concentration, and the modification of the gelatin would also contribute to the structural stabilization of the microgels. [ 40 ] It may be of scientific value to extend the current study to establish the optimal experimental conditions, such as composition, concentration, and modification of polymers to obtain the desired microgels.…”

Highly sensitive absorbance measurement using droplet microfluidics integrated with an oil extraction and long pathlength detection flow cell

“…In droplet microfluidics, discrete droplets are formed by two immiscible fluids and each single droplet acts as an individual biochemical reactor ( Shang et al, 2017 ). Chemicals mix rapidly in the droplet due to chaotic advection ( Gan et al, 2023 ; Zhang et al, 2023 ), while mixing in the laminar flow of single-phase microfluidics is mainly achieved by relatively slow diffusion process ( Ulkir et al, 2021 ). The droplet flow also reduces Taylor dispersion that is present in the single-phase flows ( Hassan et al, 2019 ; Elvira et al, 2022 ).…”

Porous Anisometric PNIPAM Microgels: Tailored Porous Structure and Thermal Response

“…[17][18][19][20][21]25] In the case of PNIPAM microgels, oil droplets [17] and solid particles [25] are used as templates in the reaction solution for droplet polymerization. Also, gas bubbles [19] and porogens [20,21,42,43] are applied as templates in porous particle synthesis. In addition to templates, in microgel synthesis, porosity can also be induced or adapted using the cononsolvency effect for bulk hydrogels, [22,23] hybrid gels, [44] or microspheres.…”