title: EMCCD-based spectrally resolved fluorescence correlation spectroscopy.
abstract: We present an implementation of fluorescence correlation spectroscopy with spectrally resolved detection based on a combined commercial confocal laser scanning/fluorescence correlation spectroscopy microscope. We have replaced the conventional detection scheme by a prism-based spectrometer and an electron-multiplying charge-coupled device camera used to record the photons. This allows us to read out more than 80,000 full spectra per second with a signal-to-noise ratio and a quantum efficiency high enough to allow single photon counting. We can identify up to four spectrally different quantum dots in vitro and demonstrate that spectrally resolved detection can be used to characterize photophysical properties of fluorophores by measuring the spectral dependence of quantum dot fluorescence emission intermittence. Moreover, we can confirm intracellular cross-correlation results as acquired with a conventional setup and show that spectral flexibility can help to optimize the choice of the detection windows.
authors.affiliation: Cell Biophysics Group, Institut Pasteur Korea, Sampyeong-dong 696, Bundang-gu, Seongnam-si, Gyeonggi-do, Republic of Korea.
authors.forename: Felix
authors.initials: F
authors.lastname: Bestvater
authors.forename: Zahir
authors.initials: Z
authors.lastname: Seghiri
authors.forename: Moon Sik
authors.initials: MS
authors.lastname: Kang
authors.forename: Nadine
authors.initials: N
authors.lastname: Gröner
authors.forename: Ji Young
authors.initials: JY
authors.lastname: Lee
authors.forename: Kang-Bin
authors.initials: KB
authors.lastname: Im
authors.forename: Malte
authors.initials: M
authors.lastname: Wachsmuth