Orthogonal Photochemistry toward Direct Encryption of a 3D-Printed Hydrogel

Di Chen; Chujun Ni; Chen Yang; Ye Li; Xin Wen; Curtis W Frank; Tao Xie; Hua Ren; Qian Zhao

doi:10.1002/adma.202209956

Orthogonal Photochemistry toward Direct Encryption of a 3D-Printed Hydrogel

Adv Mater. 2023 Apr;35(14):e2209956. doi: 10.1002/adma.202209956. Epub 2023 Feb 28.

Authors

Di Chen^{1

2}, Chujun Ni², Chen Yang², Ye Li², Xin Wen², Curtis W Frank³, Tao Xie^{1

2}, Hua Ren^{1

2}, Qian Zhao²

Affiliations

¹ Ningbo Research Institute, Zhejiang University, Ningbo, 315100, China.
² State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China.
³ Department of Chemical Engineering, Stanford University, Stanford, CA, 94305, USA.

PMID: 36656747
DOI: 10.1002/adma.202209956

Abstract

Encryption technologies are essential for information security and product anti-counterfeiting, but they are typically restricted to planar surfaces. Encryption on complex 3D objects offers great potential to further improve security. However, it is rarely achieved owing to the lack of encoding strategies for nonplanar surfaces. Here, an approach is reported to directly encrypt on a 3D-printed object employing orthogonal photochemistry. In this system, visible light photochemistry is used for 3D printing of a hydrogel, and ultraviolet light is subsequently employed to activate its geometrically complex surface through the dissociation of ortho-nitrobenzyl ester units in a spatioselective manner for information coding. This approach offers a new way for more reliable encryption, and the underlying orthogonal photochemistry can be extended toward functional modification of 3D-printed products beyond information protection.

Keywords: 3D printing; encryption of 3D surfaces; hydrogels; orthogonal photochemistry.

Abstract

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