“…The traditional analytical methods reported for the analysis of cations and anions, such as ICP-AES, AAS, and electrochemical methods, have been largely restricted due to their expensive instruments, complicated procedures, and the need for highly trained operators [13][14][15]. In contrast, fluorescence methods have shown the advantages of costeffectiveness, simplicity, easy operation, and high sensitivity [16][17][18]. While numerous fluorescent chemosensors for a single analyte have been reported, fluorescent chemosensors that allow the sequential sensing of multiple analytes with great selectivity and sensitivity are still needed [19][20][21] because they are more cost-effective, recyclable and practical [22][23][24].…”