Novel triazole-based fluorescent probes for Pd2+ in aqueous solutions: design, theoretical calculations and imaging.

The first triazole-containing fluorescent probe with excellent water-solubility for Pd(2+) was presented. The results indicated that an amide-triazole-amide binding sequence was responsible for the unique affinity of PS-1 toward Pd(2+). Among the tested metal ions, only Pd(2+) could selectively quench the fluorescence of PS-1 under physiological conditions, while other common interference ions like Pt(2+) and Ru(3+) caused little changes. The successful fluorescence imaging of Pd(2+) in HeLa cells implied the potential applications of PS-1 in biological Pd(2+)-analysis.