In this work,we proposed a ratiometric silver nanoclusters(AgNCs)fluorescent assay by designing a bifunctional-blockeraided hybridization chain reaction(HCR).Hairpin probe 1(HP1)containing two special DNA fragments(5...In this work,we proposed a ratiometric silver nanoclusters(AgNCs)fluorescent assay by designing a bifunctional-blockeraided hybridization chain reaction(HCR).Hairpin probe 1(HP1)containing two special DNA fragments(5′-CAC CGC T-3′and 5′-ATT TGC CTT TTG GGG ACG GATA-3′)at two terminals creates a red-emitting AgNC nucleation sequence(rNS,5′-CAC CGC TAT TTG CCT TTT GGG GAC GGATA-3′).We found that the presence of a toehold fragment(5′-TGCCC-3′)in HP1 could silence the rNS.Upon the addition of a target nucleic acid,HCR of HP1 and hairpin probe 2(HP2)could be initiated,resulting in the formation of long chain of DNA duplexes with multibranched rNS.As the toehold fragment in HP1participated in generating duplexes,a strong emission of rNS-templated AgNCs was observed at 670 nm.More significantly,a bifunctional blocker was introduced not only to reduce the background red-emitting fluorescence but also to play as an internal green-emitting AgNCs nucleation sequence.On the one hand,the blocker could increase the signal-to-noise-ratio of the constructed biosensor,and on the other hand,the blocker also helped to prepare ratiometric HCR-AgNCs assay with self-calibrating ability to strengthen its reproducibility.Compared with the traditional HCR-AgNCs sensors,the developed ratiometric assay based on the bifunctional-blocker-aided HCR has higher reliability,which is important for the fabrication of biosensors in various fields for practical biosensing applications.展开更多
基金supported by the National Natural Science Foundation of China(22304062)the Zhejiang Provincial Natural Science Foundation of China(LTGY24B050002)+2 种基金the Program for Science and Technology of Jiaxing(2023AY40028)the Baiqing Foundation of Jiaxing University(CD70621010)Springer Nature or its licensor(e.g.a society or other partner)holds exclusive rights to this article under a publishing agreement with the author(s)or other rightsholder(s)author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law。
文摘In this work,we proposed a ratiometric silver nanoclusters(AgNCs)fluorescent assay by designing a bifunctional-blockeraided hybridization chain reaction(HCR).Hairpin probe 1(HP1)containing two special DNA fragments(5′-CAC CGC T-3′and 5′-ATT TGC CTT TTG GGG ACG GATA-3′)at two terminals creates a red-emitting AgNC nucleation sequence(rNS,5′-CAC CGC TAT TTG CCT TTT GGG GAC GGATA-3′).We found that the presence of a toehold fragment(5′-TGCCC-3′)in HP1 could silence the rNS.Upon the addition of a target nucleic acid,HCR of HP1 and hairpin probe 2(HP2)could be initiated,resulting in the formation of long chain of DNA duplexes with multibranched rNS.As the toehold fragment in HP1participated in generating duplexes,a strong emission of rNS-templated AgNCs was observed at 670 nm.More significantly,a bifunctional blocker was introduced not only to reduce the background red-emitting fluorescence but also to play as an internal green-emitting AgNCs nucleation sequence.On the one hand,the blocker could increase the signal-to-noise-ratio of the constructed biosensor,and on the other hand,the blocker also helped to prepare ratiometric HCR-AgNCs assay with self-calibrating ability to strengthen its reproducibility.Compared with the traditional HCR-AgNCs sensors,the developed ratiometric assay based on the bifunctional-blocker-aided HCR has higher reliability,which is important for the fabrication of biosensors in various fields for practical biosensing applications.
