A superstable sandwich-type composite of a single-benzene-based fluorophore and chitosan as a fluorescent authentication barcode.

Management of diseases through medication accounts for the largest portion of treatment, with people worldwide relying on a variety of medicines to treat and prevent minor to severe diseases in modern society. However, the recent increased use of counterfeit medicines rather than certified medication has emerged as a serious social concern. This study introduces a new hybrid material, named SBBF-chitosan (SC), which integrates a single-benzene-based fluorophore (SBBF) and chitosan, serving as a fluorescence-based authentication barcode for certified medication. The synthesis and characterization of SC, along with an analysis of its photophysical properties, were systematically conducted. SC demonstrated bright emission with high stability under various environmental conditions. In vitro analyses and in vivo animal experiment results further indicated the safety of SC for oral intake, even when directly incorporated into medicines. We are confident that this newly developed formulation SC provides a fundamental solution to address the challenges posed by counterfeit medicines, thereby safeguarding medication authenticity.