Besides the single-capsule measurements, an ensemble method-rheology was also used to determine the mechanical properties of microcapsules. Different amounts of microcapsules were produced and gingerly transferred into a 15% (w/v) dextran solution dissolved in the normal saline to avoid microcapsule sedimentation during rheology measurements. The final volume fractions of microcapsule suspensions were 10% (v/v) and 40% (v/v), and pure dextran solution was used as a control sample. All rheological measurements were performed on a stress-controlled rheometer (Haake, MARS III, Thermo Fisher, USA) using concentric cylinder geometry with a bob diameter of 25.960 mm and a cup diameter of 27.200 mm. Dynamic frequency sweeps were conducted at 25 C and an strain amplitude of 𝛾 0 = 1% . This strain was confirmed by a dynamic strain sweep to be in the linear viscoelastic regime for all microcapsule suspensions. Then steady shear measurements were conducted at 25 C.