Electrical Writing Induced Covalent Cross-Linking on Hydrogel for Multidimensional Structural Information Storage

The storage of dynamic information in hydrogel is extremely interesting due to the reprogrammable and responsive features of hydrogel. Here, we report that structural information can be stored in polysaccharide hydrogel by electrically induced covalent cross-linking, and the imbedded information can be retrieved by different means (dye adsorption, protonation of chitosan, and acid dissolution). Taking the advantage of diffusible feature of hydrogel, OH- was generated from the contacting area of the electrode and controllably diffused by electrical writing, thus the high pH domain (pH similar to 10) triggered covalent cross-linking of the hydrogel. The written area exhibits different micromorphology, chemical properties, and pH sensitivity, allowing dynamic 2D and 3D information to be stored and read when necessary. This work demonstrates the use of stable electrical inputs to store dynamic structural information in a biopolymer-based hydrogel and how the chemical and physical varies allow eye recognition to the embedded information.

Automated summary

This study demonstrates the storage and retrieval of structural information in hydrogel through electrically induced covalent cross-linking. By leveraging the diffusible feature of hydrogel, different micromorphology, chemical properties, and pH sensitivity are achieved in the written area, enabling dynamic information storage in 2D and 3D formats. The use of stable electrical inputs showcases the versatility in storing dynamic structural information and allows for recognition of the embedded information through chemical and physical variations.