Multifunctional carbon dot-based dual-channel and dual-signal sensors for ribonucleotide discrimination and Fe3+ detection†

Ribonucleotides and Fe³⁺ are crucial for numerous biological processes, hence their effective discrimination and detection are imperative for the investigation of metabolic processes and the early diagnosis of diseases, yet current sensing strategies based on a single signal output are hard to fulfill the demands for practical detection accuracy. Herein, a dual-channel sensor based on copper-doped fluorescent carbon dots (Cu-CDs) as a single sensing unit has been developed for the precise discrimination of ribonucleotides. Combined with statistical analyses of the data arrays, accurate discrimination and quantification of the four most vital ribonucleotide triphosphates (ATP, CTP, UTP, and GTP) are achieved, providing a valuable reference to improve the design of complex sensor arrays. Furthermore, given the merits of dual-signal detection, a silica-based aggregation-induced emission material is further introduced as the second fluorophore. The constructed novel dual-fluorescence signal sensing system enables rapid quantitative detection (2 min) and visual semi-quantitative sensing of Fe³⁺ with enhanced accuracy and a detection limit of 1.53 μM. Briefly, such dual-signal sensors based on Cu-CDs feature easy operation, simplicity, and accuracy, offering valuable references for the design and construction of dual-channel detection tools and hold potential for practical applications.