Hydrogel Encapsulation of Cells in Core–Shell Microcapsules for Cell Delivery

Abstract

A newly designed 3D core-shell microcapsule structure composed of a cell-containing liquid core and an alginate hydrogel shell is fabricated using a coaxial dual-nozzle electrospinning system. Spherical alginate microcapsules are successfully generated with a core-shell structure and less than 300 μm in average diameter using this system. The thickness of the core and shell can be easily controlled by manipulating the core and shell flow rates. Cells encapsulated in core-shell microcapsules demonstrate better cell encapsulation and immune protection than those encapsulated in microbeads. The observation of a high percentage of live cells (≈80%) after encapsulation demonstrates that the voltage applied for generation of microcapsules does not significantly affect the viability of encapsulated cells. The viability of encapsulated cells does not change even after 3 d in culture, which suggests that the core-shell structure with culture medium in the core can maintain high cell survival by providing nutrients and oxygen to all cells. This newly designed core-shell structure can be extended to use in multifunctional platforms not only for delivery of cells but also for factor delivery, imaging, or diagnosis by loading other components in the core or shell.

Encapsulation of Autoinducer Sensing Reporter Bacteria in Reinforced Alginate-Based Microbeads

“…It cannot be excluded that the possible elongation of the cell membrane during extrusion has an additional minor effect on the cell viability. 33 To check the dynamics of E. coli pLuxR-GFP growth in alginate-based beads, beads containing approximately 300 cells at the beginning of cultivation were incubated in LB medium at 37 °C, and the bacteria population density was recorded over time using a standard plate counting method after bead lysis via citrate. Figure 6 d indicates that the growth curves of bacteria in hydrogel beads were similar to those of planktonic bacteria in bulk liquid media, including the exponential-growth phase and the saturation phase.…”

Cell‐Surface Engineering for Advanced Cell Therapy

“…[105,106] An alternative strategy for encapsulatingc ells, employing core-shell structures consisting of a liquid core bearingacell and an alginateh ydrogel shell, has recently emerged. [107] Cells encapsulated in core-shell structures have been reported to improvee ncapsulation, immune protection,c ryopreservation,t ransplantation, and cell viability. [108,109] Core-shell-encapsulated cells have usually been fabricated using droplet-based microfluidic techniques because they offer severala dvantages,s uch as controllable thickness and size with al ow size distribution, and high homogeneity.…”

Human Cell Encapsulation in Gel Microbeads with Cosynthesized Concentric Nanoporous Solid Shells

“…Cell encapsulation has been used for the delivery of therapeutic molecules in many clinical applications, such as treatment of diabetes 85 , cancer 86 , and heart disease 87 . There are many methods to encapsulate cells in microparticles, including the use of polymer membranes made of either a liquid or gel core enveloped by a gel shell structure to form droplets containing live cells 88,89 . However, current methods require step-by-step synthesis, where the core is synthetized in a first polymerization step followed by a second polymerization of the shell 90 .…”