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Core/shell nanoparticles composed of a silica core over which a propargyl methacrylate (PMA) shell was polymerized around were synthesized. To employ the shell coating, the surface of the silica nanoparticles (SiNPs) was modified with an alkene-terminated organometallic silane linker that allowed for the covalent attachment of a poly(propargyl methacrylate) (pPMA) shell. The alkyne groups resulting from the pPMA shell were utilized in copper(I)-catalyzed azide/alkyne cycloaddition (CuAAC) reactions to attach azide-modified Förster resonance energy transfer (FRET) pairs of naphthalimide (azNap), rhodamine B (azRhod), and silicon phthalocyanine (azSiPc) derivatives to the shell surface. The luminescence of the system was manipulated by the covalent attachment of one, two, or three of the fluorophores resulting in no energy transfer, one energy transfer, or two energy transfers, respectively. When all three fluorophores were attached to the core/shell particles, an excitation of azNap with a wavelength of 400 nm resulted in the sequential energy transfer between two FRET pairs and the sole emission of azSiPc at 670 nm. These particles may have applications as bioimaging probes as their luminescence is easily detected using fluorescence microscopy.
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Energy Transfer Chemiluminescent Spiroadamantane 1,2‐Dioxetane Probes for Bioanalyte Detection and Imaging
Abstract Chemiluminescence imaging of bioanalytes using spiroadamantane 1,2‐dioxetanes has gained significant attention due to improved signal‐to‐noise ratios and imaging depth compared to excitation‐based probes, as well as their modifiable scaffolds that offer analyte‐specific responses and tunable emissive properties. Among several strategies employed to amplify signals under aqueous conditions and to shift the emission into the bio‐relevant red region, energy transfer to an adjacent fluorophore is a popular and effective method. This Minireview highlights spiroadamantane 1,2‐dioxetane‐based probes that operate via an energy transfer mechanism to detect bioanalytes both in vitro and in vivo. Probes that display both non‐covalent and covalent interactions with fluorophores, as well as their applications in imaging specific analytes will be discussed.
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- Award ID(s):
- 1653474
- PAR ID:
- 10373584
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie
- Volume:
- 134
- Issue:
- 42
- ISSN:
- 0044-8249
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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