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16-Ch Time-resolved Single-Molecule Spectroscopy Using Line Excitation.

ABSTRACT: Single-molecule spectroscopy on freely-diffusing molecules allows detecting conformational changes of biomolecules without perturbation from surface immobilization. Resolving fluorescence lifetimes increases the sensitivity in detecting conformational changes and overcomes artifacts common in intensity-based measurements. Common to all freely-diffusing techniques, however, are the long acquisition times. We report a time-resolved multispot system employing a 16-channel SPAD array and TCSPC electronics, which overcomes the throughput issue. Excitation is obtained by shaping a 532 nm pulsed laser into a line, matching the linear SPAD array geometry. We show that the line-excitation is a robust and cost-effective approach to implement multispot systems based on linear detector arrays.

SUBMITTER: Ingargiola A

PROVIDER: S-EPMC5463578 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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16-Ch Time-resolved Single-Molecule Spectroscopy Using Line Excitation.

Ingargiola Antonino A Peronio Pietro P Lerner Eitan E Gulinatti Angelo A Rech Ivan I Ghioni Massimo M Weiss Shimon S Michalet Xavier X

Proceedings of SPIE--the International Society for Optical Engineering 20170101

Single-molecule spectroscopy on freely-diffusing molecules allows detecting conformational changes of biomolecules without perturbation from surface immobilization. Resolving fluorescence lifetimes increases the sensitivity in detecting conformational changes and overcomes artifacts common in intensity-based measurements. Common to all freely-diffusing techniques, however, are the long acquisition times. We report a time-resolved multispot system employing a 16-channel SPAD array and TCSPC elect ...[more]

PMID: 28603333

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