A fluorescent sensor array based on three kinds of carbon dots for identification of hydroxybenzaldehyde and nitrobenzaldehyde isomers

A fluorescent sensor array based on three kinds of carbon dots (CDs) were fabricated to discriminate hydroxybenzaldehyde and nitrobenzaldehyde isomers. Based on the Schiff base reaction, carbon dots with amino groups on the surface were designed. Fluorescence quenching of CDs occurred when hydroxybenzaldehyde and nitrobenzaldehyde isomers were combined with CDs. The sensor array showed different fluorescence patterns for each hydroxybenzaldehyde and nitrobenzaldehyde isomer in terms of fluorescence intensity change F/F0, which was further analyzed by principal component analysis (PCA). Finally, the fluorescent sensor array behaved well in differentiating and identifying hydroxybenzaldehyde and nitrobenzaldehyde isomers in aqueous solutions and distinguishing binary mixtures.