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PubMed · 16292968

Parallel dual-color fluorescence cross-correlation spectroscopy using diffractive optical elements.

Michael Gösch·Hans Blom·Sylvain Anderegg·Kerstin Korn·Per Thyberg·Mona Wells·Theo Lasser·Rudolf Rigler·Anders Magnusson·Sverker Hård
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Abstract

Dual-color cross-correlation spectroscopy allows the detection and quantification of labeled biomolecules at ultra-low concentrations, whereby the sensitivity of the assay correlates with the measurement time. We now describe a parallel multifocal dual-color spectroscopic configuration employing multiple avalanche photodiodes and hardware correlators. Cross-correlation curves are obtained from several dual-color excitation foci simultaneously. Multifocal dual-color excitation is achieved by splitting each of two laser beams (488 and 633 nm) into four sub-beams with the help of two 2x2 fan-out diffractive optical elements (DOEs), and subsequent superposition of the two sets of four foci. The fluorescence emission from double-labeled biomolecules is detected by two 2x2 fiber arrays.

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Equipment DesignEquipment Failure AnalysisFeasibility StudiesMicroscopy, Fluorescence, MultiphotonOligonucleotide Array Sequence AnalysisRefractometryReproducibility of ResultsSensitivity and SpecificitySpectrometry, FluorescenceEvaluation StudyJournal ArticleResearch Support, Non-U.S. Gov't

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Michael Gösch, Hans Blom, Sylvain Anderegg, Kerstin Korn, Per Thyberg, Mona Wells, Theo Lasser, Rudolf Rigler, Anders Magnusson, Sverker Hård. Parallel dual-color fluorescence cross-correlation spectroscopy using diffractive optical elements.. https://doi.org/10.1117/1.2080707

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