A Biosynthesis Method of Color-tunable Fluorescent Cellulose via In situ Polymerization Using Microbial Systems

In recent years, cellulose-based fluorescent polymers have received considerable attention. However, conventional modification methods face challenges such as insolubility in most solvents, fluorescence instability, and environmental risks. In this study, a novel biosynthesis strategy was developed to fabricate fluorescent cellulose by adding fluorescent glucose derivatives to a bacterial fermentation broth. The metabolic activity of bacteria is utilized to achieve in situ polymerization of glucose and its derivatives during the synthesis of bacterial cellulose. Owing to the structural similarity between triphenylamine-modified glucose (TPA-GlcN) and glucose monomers, the TPA-GlcN were efficiently assimilated by the bacterial cells and incorporated into the cellulose matrix, resulting in a uniform distribution of fluorescence. The fluorescence color and intensity of the obtained cellulose could be adjusted by varying the amount of the fluorescent glucose derivatives. Compared to the fluorescent cellulose synthesized through physical dyeing, the fluorescence of the products obtained by in situ polymerization showed higher intensity and stability. Furthermore, fluorescent bacterial cellulose can be hydrolyzed into nanocellulose-based ink, which demonstrates exceptional anti-counterfeiting capabilities under UV light. This biosynthesis method not only overcomes the limitations of traditional modification techniques but also highlights the potential of microbial systems as platforms for synthesizing functional polymers.