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International Journal of Bioprinting 4D heterojunction shape reconfiguration by two-photon polymerization

A B

C D

E F

G H

Figure 4. (A) Tunable photon filtering from a white light source using the MNIH PCs, color shifted as the CCD images. (B) The visibly-highlighted
structural coloration and transmission spectra of PCs, and spectral characters matched well with the microscale footprint coloration. (C) Phase image,
fluorescence image, and merged image of the tested MNIHs in cell cytotoxicity test. Sample 1 was a single-layer PC, and sample 2 was an array of
hollow hexahedrons, where the pencil-shape fibroblast cells were crawling on hydrogel block. (D) Cell viability summary of Figure 3C across 1 week on
MNIHs. Both samples maintained cell viability ratio of over 95%. (E) The mechanism of self-assembling PEG molecules for repairing damaged fissures.
(F) An impaired heart-shaped MNIH self-recovered to its initial symmetric shape. (G) A poked hole in planar MNIHs absorbed PEG-400 molecules to
reconstruct the damaged areas, confirming the highly-valuable autonomic repairing process. (H) A similar self-healing process could be found in other
mechanically-damaged flower-shaped MNIHs with the aid of PEG-400

4. Conclusions small loads of stimuli), and maximized it substantially
at nanometer precision. As exhibited, the reverse
Based on the investigation described in the above, we first molecular interaction and the resultant stretching
confirmed that the monolayer heterojunction scanning and contracting all become tunable at the basic unit
strategy promised an unimaginable capacity of μ/n of single nanowires (the most precise programming
scale, high-controllable shape reconfiguration for actual unit at least three-order smaller than the reported
requirements. Then, this method exhibited superior 3D-printed robotics) for the first time.
advantages over the orthodox 3D printing in a few aspects: (ii) Subsequently, multiple reconfigurations in one
(i) Basically, the flexible fsLDW incorporating starting shape now became accessible by proper
interactives hydrogels inherited the materials’ potential design, which promised more mechanical mutations
(amphipathic, soft mechanics, self-adaptiveness to to μ/n robotics for complex functions. Many other

Volume 9 Issue 3 (2023) 21 https://doi.org/10.18063/ijb.678