This Article Full Text Full Text (PDF) All Versions of this Article: biophysj.107.126193v1 95/1/390    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Google Scholar Articles by Ries, J. Articles by Schwille, P. PubMed PubMed Citation Articles by Ries, J. Articles by Schwille, P.

Total Internal Reflection Fluorescence Correlation Spectroscopy: Effects of Lateral Diffusion and Surface-Generated Fluorescence

Biotechnologisches Zentrum, Technical University of Dresden, Dresden, Germany

Correspondence: Address reprint requests to Petra Schwille, Tel.: 49-351-463-40328; E-mail: schwille{at}biotec.tu-dresden.de.

Fluorescence correlation spectroscopy with total internal reflection excitation (TIR-FCS) is a promising method with emerging biological applications for measuring binding dynamics of fluorescent molecules to a planar substrate as well as diffusion coefficients and concentrations at the interface. Models for correlation functions proposed so far are rather approximate for most conditions, since they neglect lateral diffusion of fluorophores. Here we propose accurate extensions of previously published models for axial correlation functions taking into account lateral diffusion through detection profiles realized in typical experiments. In addition, we consider the effects of surface-generated emission in objective-based TIR-FCS. The expressions for correlation functions presented here will facilitate quantitative and accurate measurements with TIR-FCS.