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Probing emission of a DNA-stabilized silver nanocluster from the sub-nanosecond to millisecond timescale in a single measurement.

ABSTRACT: A method for measuring emission over a range of sub-nanosecond to millisecond timescales is presented and demonstrated for a DNA-stabilized silver nanocluster (DNA-AgNC) displaying dual emission. This approach allows one to disentangle the temporal evolution of the two spectrally overlapping signals and to determine both the nano- and microsecond decay times of the two emission components, together with the time they take to reach the steady-state equilibrium. Addition of a second near-infrared laser, synchronized with a fixed delay, enables simultaneous characterization of optically activated delayed fluorescence (OADF). For this particular DNA-AgNC, we demonstrate that the microsecond decay times of the luminescent state and the OADF-responsible state are similar, indicating that the OADF process starts from the luminescent state.

SUBMITTER: Liisberg MB

PROVIDER: S-EPMC9116328 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature

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Probing emission of a DNA-stabilized silver nanocluster from the sub-nanosecond to millisecond timescale in a single measurement.

Liisberg Mikkel Baldtzer MB Krause Stefan S Cerretani Cecilia C Vosch Tom T

Chemical science 20220421 19

A method for measuring emission over a range of sub-nanosecond to millisecond timescales is presented and demonstrated for a DNA-stabilized silver nanocluster (DNA-AgNC) displaying dual emission. This approach allows one to disentangle the temporal evolution of the two spectrally overlapping signals and to determine both the nano- and microsecond decay times of the two emission components, together with the time they take to reach the steady-state equilibrium. Addition of a second near-infrared ...[more]

PMID: 35694333

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