Demonstration of Selective Single-Barium Ion Detection with Dry Diazacrown Ether Naphthalimide Turn-on Chemosensors.
Pawan ThapaNicholas K ByrnesAlena A DenisenkoJames X MaoAustin D McDonaldCharleston A NewhouseThanh T VuongKatherine WoodruffKwangho NamDavid R NygrenBenjamin J P JonesFrank W FossPublished in: ACS sensors (2021)
Single-molecule fluorescence imaging (SMFI) of gas-phase ions has been proposed for "barium tagging," a burgeoning area of research in particle physics to detect individual barium daughter ions. This has potential to significantly enhance the sensitivity of searches for neutrinoless double-beta decay (0νββ) that is obscured by background radiation events. The chemistry required to make such sensitive detection of Ba2+ by SMFI in dry Xe gas at solid interfaces has implications for solid-phase detection methods but has not been demonstrated. Here, we synthesized simple, robust, and effective Ba2+-selective chemosensors capable of function within ultrapure high-pressure 136Xe gas. Turn-on fluorescent naphthalimide-(di)azacrown ether chemosensors were Ba2+-selective and achieved SMFI in a polyacrylamide matrix. Fluorescence and NMR experiments supported a photoinduced electron transfer mechanism for turn-on sensing. Ba2+ selectivity was achieved with computational calculations correctly predicting the fluorescence responses of sensors to barium, mercury, and potassium ions. With these molecules, dry-phase single-Ba2+ ion imaging with turn-on fluorescence was realized using an oil-free microscopy technique for the first time-a significant advance toward single-Ba2+ ion detection within large volumes of 136Xe, plausibly enabling a background-independent technique to search for the hypothetical process of 0νββ.
Keyphrases
- single molecule
- sensitive detection
- living cells
- quantum dots
- loop mediated isothermal amplification
- fluorescent probe
- fluorescence imaging
- electron transfer
- energy transfer
- atomic force microscopy
- label free
- high resolution
- real time pcr
- magnetic resonance
- photodynamic therapy
- room temperature
- optical coherence tomography
- mass spectrometry
- molecular dynamics
- density functional theory
- high throughput
- fatty acid
- molecular dynamics simulations
- candida albicans
- high speed
- staphylococcus aureus