Multichannel sensor array of carbon dots-metal ion pairs for accurate biological thiols analysis and cancer cell discrimination

Abstract Biological thiols are essential for mediating physiological and pathological processes. Because of their similarity of structures and reactivity properties, it is a challenging but significant task to identify different types of biological thiols. Herein, a multichannel sensor array was constructed to identify biological thiols based on three-color emitting carbon dots (CDs)-metal ion pairs. Primarily, three metal ions (Cu2+, Ag+, and Fe3+) were selected to quench the fluorescence signals of the three CDs, respectively. Upon the addition of thiols, the fluorescence intensities of the three CDs can be restored or further quenched owing to the synergistic coordinative and steric hindrance effect of the interaction and between thiols, metal ions and the three CDs. Recur to statistical analysis methods, the multichannel sensor array can effectively discriminate six thiols in serum and urine media using only a single “well”. Moreover, the present multichannel sensor array can also be effectively identified cell type from normal or cancer cells. Collectively, the versatile sensor array based on CDs-metal ion pairs offers a highly discerning and adaptive alternative for identifying biological thiols, which exhibit great potential in point-of-care clinical diagnostics.