Fig. 3: Cell loading and release from S-cryoMNs.

A Screening of cryogenic formulations for S-cryoMNs with low toxicity. The relative cell viability in each cryoprotective medium was calculated by normalization to that of the positive control 10% DMSO (v/v) in DPBS. B Digital images of S-cryoMNs before and after thawing. Scale bar: 2 mm. C Live/dead staining of A375 cells after their release from S-cryoMNs. Scale bar: 200 μm. D Confocal images of S-cryoMNs loaded with A375 labeled with CellTracker™ (green). Scale bar: 200 μm. E Top view confocal images and (F) quantification of the cells released from S-cryoMNs loaded with different cell densities ranging from 2.5 × 10⁶, 5.0 × 10⁶, and 7.5 × 10⁶ to 1.0 × 10⁷ cells/ml. G Top view and (H) 3D reconstruction of the confocal images showing cell release from S-cryoMNs into the agarose gel phantom. Scale bar: 100 μm. *p ≤ 0.05, **p ≤ 0.01, ***p ≤ 0.001; ns: p > 0.05, no significant difference (ns).