Promising carbonized polymer dots for visually sequential sensing of Cu2+and S2

Carbonized polymer dots (CPDs) are formed by combining lignite, which primarily forms carbon cores, with polyvinylpyrrolidone, citric acid and tryptophan, which primarily produce short polymer chains and surface functional groups. These CPDs display a unique core-shell structure, excellent optical stability, superior fluo-rescence intensity, high quantum yield (QY) and outstanding biocompatibility allowing them to be well suited for application as fluorescent sensors. CPDs can be employed both as smart sensing systems for visual detection and absorption of Cu2+ and S2-through hydrogel sensors and as fluorescent inks for information security and anti -counterfeiting. More importantly, the paper-based platform and smartphone assistance enable visual real-time on-site quantification of Cu2+ and S2-, which offers an effective tool for fast and accurate Cu2+ and S2- iden-tification and information encryption with high selectivity and sensitivity. In addition, with its good biocom-patibility and low cytotoxicity, the CPDs have been successfully utilized for imaging Cu2+ and S2-in MG-63 cells, thus making a positive contribution to the analysis and imaging of the effects of Cu2+ and S2-in relevant bio-logical processes and promoting better diagnosis and treatment of diseases.

Automated summary

Carbonized polymer dots (CPDs) are synthesized by combining lignite with polyvinylpyrrolidone, citric acid, and tryptophan, resulting in a unique core-shell structure with excellent optical stability, superior fluorescence intensity, high quantum yield, and outstanding biocompatibility. CPDs can be utilized as smart sensing systems for visual detection and absorption of Cu2+ and S2- and as fluorescent inks for information security and anti-counterfeiting. The paper-based platform and smartphone assistance enable real-time on-site quantification of Cu2+ and S2-, offering a tool for fast and accurate identification and information encryption. Additionally, CPDs have been successfully used for imaging Cu2+ and S2- in MG-63 cells, contributing to the analysis and imaging of their effects in biological processes and improving disease diagnosis and treatment.