Supramolecular co-assemblies with bioluminescent color-changing properties have shown great potential as intelligent fluorescent materials, capable of responding to stimuli from biological sources. However, to date, there have been few reports on supramolecular systems that simultaneously possess both bioluminescent color-changing and biologically fuel-driven transient assembly.

  Recently, our research group reported a novel transient bioluminescent color-changing system constructed through a simple co-assembly strategy, in which the fluorescence signal of π-conjugated units can be reversibly modulated on a time scale through enzyme-mediated processes. This system demonstrates the potential for color variability and repeatability in rewritable secure printing. Specifically, we first designed and synthesized a tetravalent cationic diacetylene anthracene monomer that can self-assemble in water and exhibit fluorescence emission. Upon addition of adenosine triphosphate (ATP) as a biological fuel, supramolecular co-assembly is formed, accompanied by quenching of the emission signal. By transiently regulating ATP consumption using the hydrolytic enzyme alkaline phosphatase (ALP), the co-assembly is disrupted, and the fluorescence color can be changed through the repeated addition of new batches of ATP. The resulting transient bioluminescent supramolecular assemblies can be used as secure inks, thereby developing rewritable secure printing materials with unique time-encoded features, greatly enhancing the security and repeatability of paper-based confidential information.

The research findings, titled "Time-encoded bio-fluorochromic supramolecular co-assembly for rewritable security printing," have been published in Chemical Science, with the DOI: 10.1039/D1SC03105.

The paper can be accessed at the following link: https://doi.org/10.1039/D1SC03105H. Associate Professor Zhao Gao and Professor Wei Tian from our research group are the first author and corresponding author of the paper, respectively.