Fig. 1.

Synthesis and characterisation of HA microcarriers (HAMCs). A. Schematic diagram of the preparation of HAMCs and IMRC culture at large-scale (Created with BioRender.com). a-c) The preparation of hyaluronic acid microspheres using the oil-in-water emulsification method, with the preconfigured pre-crosslinked aqueous phase, to produce HA-NHS ester. The HA-NHS ester was encapsulated by type I collagen to prepare HAMC. d) IMRCs expansion on HAMC in the bioreactor. e) Schematic diagram of HAMC cross-linking. The formation of HA-NHS ester was achieved by EDC/NHS, followed by the condensation of carboxyl and amino groups of collagen type I to create amide bonds. B. Diagram of HAMC particle size. C. FTIR Spectroscopy analysis of HA, HA-NHS ester, HAMC, and NHS. D. Elemental mapping of HAMC.