Chiroptical Nanocellulose Bio‐Labels for Independent Multi‐Channel Optical Encryption

Abstract

Advanced multiplexing optical labels with multiple information channels provide a powerful strategy for large‐capacity and high‐security information encryption. However, current optical labels face challenges of difficulty to realize independent multi‐channel encryption, cumbersome design, and environmental pollution. Herein, multiplexing chiroptical bio‐labels integrating with multiple optical elements, including structural color, photoluminescence (PL), circular polarized light activity, humidity‐responsible color, and micro/nano physical patterns, are constructed in complex design based on host‐guest self‐assembly of cellulose nanocrystals and bio‐gold nanoclusters. The thin nanocellulose labels exhibit tunable circular polarized structural color crossover the entire visible wavelength and circularly polarized PL with the highest‐recorded dissymmetry factor up to 1.05 due to the well‐ordered chiral organization of templated gold nanoclusters. Most importantly, these elements can independently encode customized anti‐counterfeiting information to achieve five independent channels of high‐level anti‐counterfeiting, which are rarely achieved in traditional materials and design counterparts. Considering the exceptional seamless integration of five independent encryption channels and the recyclable features of labels, the bio‐labels have great potential for the next generation anti‐counterfeiting materials technology.

Application of Multicolor Fluorescent Carbon Dots Based on Tea Polyphenols in a White Light-Emitting Diode and Room-Temperature Phosphorescence

“…The photostability and difficult preparation of CDs exhibiting room-temperature phosphorescence (RTP) make them ideal candidates for designing information encryption and decryption systems. − Developing composite systems involving mixed CDs@solid relies on establishing covalent bonds between the CDs and matrices, commonly employed to achieve stable and long-lived room-temperature phosphorescence (RTP). Specifically, the in situ hydrolysis of tetraethyl orthosilicate (TEOS) has been utilized to create covalent bonds with CDs.…”

Biomimetic Mechanically Robust Chiroptical Hydrogel Enabled by Hierarchical Bouligand Structure Engineering

“…CNCs have been synthesized from wood pulp according to the previously reported method. 61 Briefly, 17 g of wood pulp was added to a 64 wt % sulfuric acid solution and stirred in a constant temperature water bath at 45 °C. After reacting for 45 min, the solution was poured into 3 L of deionized water.…”

Stimulus-responsive polymer materials toward multi-mode and multi-level information anti-counterfeiting: recent advances and future challenges

“…In particular, their adjustable optical properties have seen SRPs widely utilized in the field of information storage and anti-counterfeiting, and have aroused great interest. Specifically, when exposed to an external stimulus, such as light, 23,24 temperature, 25,26 ions, 27,28 electricity, 29,30 magnetic, 31,32 mechanical force, 33,34 humidity 35,36 (Fig. 1a), such intelligent systems undergo obvious photophysicochemical characteristics alteration.…”