title: Parallel dual-color fluorescence cross-correlation spectroscopy using diffractive optical elements.
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.
authors.affiliation: Karolinska Institute, Department of Medical Biochemistry and Biophysics, SE-17177 Stockholm. michael.goesch@epfl.ch
authors.forename: Michael
authors.initials: M
authors.lastname: Gösch
authors.forename: Hans
authors.initials: H
authors.lastname: Blom
authors.forename: Sylvain
authors.initials: S
authors.lastname: Anderegg
authors.forename: Kerstin
authors.initials: K
authors.lastname: Korn
authors.forename: Per
authors.initials: P
authors.lastname: Thyberg
authors.forename: Mona
authors.initials: M
authors.lastname: Wells
authors.forename: Theo
authors.initials: T
authors.lastname: Lasser
authors.forename: Rudolf
authors.initials: R
authors.lastname: Rigler
authors.forename: Anders
authors.initials: A
authors.lastname: Magnusson
authors.forename: Sverker
authors.initials: S
authors.lastname: Hård
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D005240:Feasibility Studies; D036641:Microscopy, Fluorescence, Multiphoton / Q000295:instrumentation* / Q000379:methods; D020411:Oligonucleotide Array Sequence Analysis / Q000295:instrumentation* / Q000379:methods; D012031:Refractometry / Q000295:instrumentation* / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence / Q000295:instrumentation* / Q000379:methods