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Dual-locked spectroscopic probes for sensing and therapy


Optical imaging probes allow us to detect and uncover the physiological and pathological functions of an analyte of interest at the molecular level in a non-invasive, longitudinal manner. By virtue of simplicity, low cost, high sensitivity, adaptation to automated analysis, capacity for spatially resolved imaging and diverse signal output modes, optical imaging probes have been widely applied in biology, physiology, pharmacology and medicine. To build a reliable and practically/clinically relevant probe, the design process often encompasses multidisciplinary themes, including chemistry, biology and medicine. Within the repertoire of probes, dual-locked systems are particularly interesting as a result of their ability to offer enhanced specificity and multiplex detection. In addition, chemiluminescence is a low-background, excitation-free optical modality and, thus, can be integrated into dual-locked systems, permitting crosstalk-free fluorescent and chemiluminescent detection of two distinct biomarkers. For many researchers, these dual-locked systems remain a ‘black box’. Therefore, this Review aims to offer a ‘beginner’s guide’ to such dual-locked systems, providing simple explanations on how they work, what they can do and where they have been applied, in order to help readers develop a deeper understanding of this rich area of research.

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Fig. 1: Dual-locked probes containing two reaction sites that undergo two sequential reactions.
Fig. 2: Dual-locked probes containing one reaction site that undergoes two sequential reactions.
Fig. 3: Dual-locked probes containing two reaction sites enabling signal activation and targeting.
Fig. 4: Dual-locked probes containing one fluorophore that can undergo two independent reactions.
Fig. 5: Dual-locked probes based on two luminophores for duplex imaging.
Fig. 6: AND-logic-based unimolecular fluorogenic probes.
Fig. 7: AND-logic-based system using two precursor probes.
Fig. 8: Förster resonance energy transfer in the construction of dual-locked fluorescent probes.
Fig. 9: Sequential addition of two analytes to induce two different fluorescence channels in a dual-locked system.
Fig. 10: Other types of dual-locked fluorescent probes.


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L.W. wishes to thank China Scholarship Council and the University of Bath for supporting his PhD work in the UK. T.D.J. would like to thank the Engineering and Physical Sciences Research Council (EPSRC) and the University of Bath for funding. T.D.J. wishes to thank the Royal Society for a Wolfson Research Merit Award and the Open Research Fund of the School of Chemistry and Chemical Engineering, Henan Normal University for support (2020ZD01). K.P. thanks Singapore Ministry of Education, Academic Research Fund Tier 1 (2019-T1-002-045, RG125/19), Academic Research Fund Tier 2 (MOE2018-T2-2-042), and A*STAR SERC AME Programmatic Fund (SERC A18A8b0059) for the financial support.

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L.W. and J.H. contributed equally to this paper. J.H. and K.P. researched data and contributed to the writing of the introduction and the first and the third main sections. L.W. and T.D.J. researched data and contributed to the preparation of the synopsis, writing of the other four main sections, and abstract and conclusion. All the authors contributed to the discussion, writing, reviewing and editing of the synopsis and manuscript.

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Correspondence to Kanyi Pu or Tony D. James.

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Nature Reviews Chemistry thanks J. Chan, J. Rao and T. Gunnlaugsson for their contribution to the peer review of this work.

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Wu, L., Huang, J., Pu, K. et al. Dual-locked spectroscopic probes for sensing and therapy. Nat Rev Chem 5, 406–421 (2021).

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