Colorimetric multi-channel sensing of metal ions and advanced molecular information protection based on fish...

Some nanosystems based on carbon nanomaterials have been used for fluorescent chemical/biosensing, elementary information processing, and textual coding. However, little attention has been paid to utilizing biowaste-derived carbon nanomaterials for colorimetric multi-channel sensing and advanced molecular information protection (including text and pattern information). Herein, fish scale-derived carbon nanoparticles (FSCN) were prepared and used for colorimetric detection of metal ions, encoding, encrypting and hiding text- and pattern-based information. The morphology and composition of FSCN were analyzed by TEM, XRD, FTIR, and XPS, and it was found that the FSCN-based multi-channel colorimetric sensing system can detect Cr⁶⁺ (detection limit of 56.59 nM and 13.32 nM) and Fe³⁺ (detection limit of 81.55 nM) through the changes of absorption intensity at different wavelengths (272, 370, and 310 nm). Moreover, the selective responses of FSCN to 20 kinds of metal ions can be abstracted into a series of binary strings, which can encode, hide, and encrypt traditional text-based and even two-dimensional pattern-based information. The preparation of carbon nanomaterials derived from waste fish scales can stimulate other researcheres' enthusiasm for the development and utilization of wastes and promoting resource recycling. Inspired by this work, more researches will continue to explore the world of molecular information technology.