The Analytical Method Of Copper Nanoclusters As Fluorescent Probes Was Studied

As promising substitutes to common fluorophores like organic dyes, DNA or oligonucleotide templated fluorescent metal nanoclusters or nanoparticles have attracted increasing attention in the past decade, due to their low toxicity, good biocompatibility, outstanding fluorescence properties. It would be of great interest to probe the application of the dsDNA-CuNCs in the field of bioanalysis. The details are described as follows:1. Simple and sensitive fluorescence strategy for detection of uracil-DNA glycosylase activity using dsDNA-templated copper nanoclusters as probesSensitive detection of uracil-DNA glycosylase (UDG) activity is critical for function study of UDG and clinical diagnosis. Herein we exploit dsDNA-templated copper nanoclusters (CuNCs) as a fluorescent nano-dye for UDG assay. The UDG-catalyzed uracil removal can liberate ssDNA from uracil-containing dsDNA substrate, and thus the introduction of Cu2+ and ascorbate cannot form the fluorescent CuNCs due to the lack of the dsDNA templates. By optimizing the numbers and location of uracil on the DNA strand, a low detection limit of 0.0005 U/mL was achieved. The simple and rapid method may hold potential applications in UDG-related clinical diagnosis and functional research.2. Simple and sensitive fluorescence strategy for detection of glutathione using copper nanoclusters as probesIn this work, we design a ssDNA repeated by AT sequence,and this ssDNA can self hybridizate into dsDNA,which can act as the effective templates for CuNCs and show very strong fluorescence intensity. Thiol compounds and Cu2+ can form a complex, and the fluorescence of CuNCs was tremendously quenched through a robust Cu-S bond between-SH in glutathione molecule and Cu of CuNCs.When added glutathione,which would inhibit the formation of fluorescent CuNCs. Hence, glutathione could be detected through the changes of the fluorescence intensity of the system. A good linear relationship was obtained between the FL intensity and the concentrations of glutathione in the range of 0.01 ?M?1?M, with a detection limit at 3.9 nM which was three orders lower than the reported work, which Shows a good application prospect.