Fluorescence cross correlation

Swift, J. L., Heuff, R. F. and Cramb, D. T. (2006) A two-photon excitation fluorescence cross-correlation assay for a model ligand-receptor binding system using quantum dots. Biophys. J., 90, 1396-1410. 

Rigler, R., Foldes-Papp, Z., Meyer-Almes, F. J., Sammet, C., Volcker, M. and Schnetz, A. (1998). Fluorescence cross-correlation A new concept for polymerase chain reaction. J. Biotechnol. 63, 97-109. 

Kogure, T., Karasawa, S., Araki, T., Saito, K., Kinjo, M., and Miyawaki, A. 2006. A fluorescent variant of a protein from the stony coral Montipora facilitates dual-color singlelaser fluorescence cross-correlation spectroscopy. Nature Biotechnol. 24 577-81. 

Dittrich, P.S., Schwille, R, Spatial two-photon fluorescence cross-correlation spectroscopy for controlling molecular transport in microfluidic structures. Anal. Chem. 2002, 74(17), 4472-4479. 

Reviews listed in Further Reading provide excellent introductions to PCS. Related techniques have been developed to detect other molecular properties. These properties include fluorescence cross-correlation spectroscopy (FCCS) (28) to detect codiffusing fluorophores and photon-counting histograms (PCH) (29), or fluorescence intensity distribution analysis (FIDA) (29) to distinguish fluorescent species according to their brightness. 

The potential of fluorescence cross correlation (FXS) has been outlined by Eigen and Rigler [54]. Compared to FRET which gives information about the vicinity of fluorescent centers FXS gives Information about their connectivity in the dynamic sense independent of how close or far away the fluorescent centers are positioned. A detailed theoretical description has been provided [55,56[ and FXS has been used successfully in a variety of applications both in solution as well as at the cellular level. C. Zeiss with his Confocor 2 (for solution measurements) and Confocor 3 (for cellular measurements) has provided instruments of highest sensitivity. 

Bacia, K. and Schwille, P. (2007) Practical guidelines for dual-color fluorescence cross-correlation spectroscopy. Nature Protocols, 2, 2842-2856. 

There are, however, limits in the resolution of heterogeneous populations. In the particular case of multiple diffusing fluorescent species, for example in binding studies, the diffusion times must differ by a factor of 1.6-2.0 to be resolved, corresponding to a 4-8-fold increase in molecular weight. This limitation is alleviated in dual-color fluorescence cross-correlation spectroscopy (DC-FCCS) [116], in which the fluorescence fluctuation is simultaneously recorded in the same observation volume for two different species labeled with distinguishable fluorophores. The fraction of double-labeled and hence associated species is derived from the cross-correlation function between the two fluorescences (fig. 3.4B). 

Foldes-Papp, Z and Rigler, R, Quantitative two-color fluorescence cross-correlation spectroscopy in the analysis of polymerase chain reaction. Biological Chemistry3S2 (2001) 473-478. 

LeCaptain, DJ and Van Orden, A, Two-beam fluorescence cross-correlation spectroscopy in an electrophoretic mobflity shift assay. Analytical Chemistry 74 (2002) 1171 1176. 

As in most other experimental techniques, there is also a constant development and improvement involved in FCS which broadens its range, applicability, and accuracy. These developments resulted in advances such as dual-focus FCS, total internal reflection FCS, and STED-FCS which will be discussed in this section. Apart from this progress, a multitude of other variations have been reported which cannot be covered within this book chapter. These include FCS with two-photon excitation [57-61], spatial fluorescence cross-correlation spectroscopy (FCCS) which can be used to investigate microflows [62], dual-color FCCS to correlate... 

Schwille P, Meyer-Almes FJ, Rigler R (1997) Dual-color fluorescence cross-correlation spectroscopy for multicomponent diffusional analysis in solution. Biophys J 72 (4) 1878-1886... 

Yordanov S, Best A, Butt H-J, Koynov K (2009) Direct studies of liquid flows near solid surfaces by total internal reflection fluorescence cross-correlation spectroscopy. Opt Express 17(23) 21149-21158... 

Jahnz, M., Schwille, P. An ultrasensitive site-specific DNA recombination assay based on dual-color fluorescence cross-correlation spectroscopy. Nucleic Acids Res. 33, e60 (2005)... 

D. Lumma, A. Best, A. Gansen, F. Feuillebois, J. 0. Radler, and 0. 1. Vinogradova, Flow profile near a wall measured by double-focus fluorescence cross-correlation, Phys. Rev. E, 67,056313 [2003]. 

Rigler, R. Mets, U. Widengren, J. et al. Fluorescence Correlation Spectroscopy with high Count Rate and low Background - Analysis of Translational Diffusion. Eur. Biophys. J. Biophys. Lett. 1993, 22, 169-175. Bacia, K. Majoul, I. V. Schwille, P. Probing the endocytic pathway in live cells using dual-color fluorescence cross-correlation analysis. Biophys. J. 2002, , 1184-1193. 

Weidemann, T. Wachsmuth, M. Tewes, M. Rippe, K. Langowski, J. Analysis of Ligand Binding by Two-Colour Fluorescence Cross-Correlation Spectroscopy. Single Mol. 2002, 3, 49-61. 

Leutenegger, M. Blom, H. Widengren, J. Eggeling, C. GOsch, M. Leitgeb, R. A. Lasser T. Dual-color Total Internal Reflection Fluorescence cross-Correlation Spectroscopy. J. Biomed. Opt. 2006, II, accepted for publication. 

DC-FCCS Dual-color fluorescence cross-correlation spectroscopy DLS Dynamic light scattering... 

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