Dual‐Functionalisation of Fluorophores for the Preparation of Targeted and Selective Probes

Abstract

A key current challenge in biological research is the elucidation of the that roles chemicals and chemical reactions play in cellular function and dysfunction. Of the available cellular imaging techniques, fluorescence imaging offers a balance between sensitivity and resolution, enabling the cost‐effective and rapid visualisation of model biological systems. Importantly, the use of responsive fluorescent probes in conjunction with ever‐advancing microscopy and flow cytometry techniques enables the visualisation, with high spatiotemporal resolution, of both specific chemical species and chemical reactions in living cells. Ideal responsive fluorescent probes are those that contain a fluorophore tethered to both a sensing unit, to ensure selectivity of response, and a targeting group, to control the sub‐cellular localisation of the probe. To date, probes that are both targeted and selective are relatively rare and most localised probes are discovered serendipitously rather than by design. A challenge in this field is therefore the identification of suitable fluorophore scaffolds that can be readily attached to both sensing and targeting groups. Here we review current strategies for dual‐functionalisation of fluorophores, highlighting key examples of targeted, responsive probes.

Photocleavable Fluorescent Membrane Tension Probes: Fast Release with Spatiotemporal Control in Inner Leaflets of Plasma Membrane, Nuclear Envelope, and Secretory Pathway

“…The targeting of fluorescent probes to different organelles inside cells has been widely explored. Probes equipped with empirical “tracker” groups can be simply added to cells and find their targets by different, sometimes unknown mechanisms [13, 14] . With the alternative genetic engineering approach, probes are attached to ligands for proteins that are expressed at specific sites [15] .…”

Versatile naphthalimide tetrazines for fluorogenic bioorthogonal labelling

“…32 In addition, they can be readily synthetically modified at the imide, 4-amino-position and 3-, 5-or 6-positions of the naphthalene core. 32,33 There are some reports of fluorogenic naphthalimides for biological imaging and protein labelling, with the fluorogenic changes arising from click reactions involving azides and alkynes, 34 SNAP tags, 35 sydnones, 36 and oximes. 37 However, there are no reports of fluorogenic 4-amino-naphthalimides incorporating tetrazines for biological imaging.…”

NIR-II cell endocytosis-activated fluorescent probes for in vivo high-contrast bioimaging diagnostics

“…Besides tumor imaging based on passive targeting, equipping CEAF probes with affinity ligands will enable cell-specic diagnostics. 43,44 Traumatic arthritis (TA) caused by intense external force is an acute inammatory disease and its early recognition and treatment is essential for achieving effective therapeutic outcome. 45 It was reported that the inammatory response aer TA involves the recruitment of M1 macrophages with highly overexpressed integrin a v b to the articular cavity, which can be a potential biomarker for early diagnosis of TA.…”