Persistence length estimation of polythymine and human telomere using fluorescence correlation spectroscopy

Abstract

We aimed to widen Fluorescence Correlation Spectroscopy (FCS) utility in analysis of single stranded DNA. The FCS is known to have two major advantages in measurement. First is that the FCS is one of non-invasive equipment that hardly damage the sample of interest. Thus, the biological molecule is investigated at almost intact state. Second, FCS experiment is carried out at the tiny sample amount so that the sample consumption is reduced and the potential intermolecular effect, which may be risky in the high concentration experiment, is ruled out. To widen the utility of FCS, we attempts 1. to obtain persistence length estimation of random coil of polymer

single stranded DNA and 2. to obtain cooperativity of G quadruplex stabilized by monovalent ion for example K+ ion and 3. to analyze ssDNA to realize the sequence dependent physical characteristics. These were done by FCS thus the advantages of FCS is inherited to obtain and analyze physical characteristics of biomolecules. The persistence length and cooperativity which are obtained from FCS measurement are consistent with the work of others. The observation of bond length shortening of human telomere is well discussed.