Scheme 1. Schematic Illustration of the Combination of Microreactors and HepG2 Cells.

(a) Assembly: schematic illustration of the Alg particle fabrication using D-μF and their coating with poly(l-lysine) (PLL) or cholesterol-modified poly(methacrylic acid) (PMA) (PMAc) (right inset). Two types of microreactors are assembled: AlgL_cat consisting of Alg carrier particles with entrapped catalase-loaded liposomal subunits (L_cat) and Algcat consisting of Alg carrier particles with entrapped catalase (cat) (left inset). (b) Microreactors and HepG2 cells are mixed in solution, followed by their co-culturing. The HepG2 cells are allowed to be in planar cell culture and in cell aggregates. (c) These combinations of synthetic microreactors and HepG2 cells are exposed to hydrogen peroxide (H₂O₂), and the ability of the artificial partner to support the viability of the HepG2 cells is assessed.