Naslov
Dielectric Spectroscopy of DNA Aqueous Solutions

Autori
Tomić, Silvia ; Dolanski Babić, Sanja ; Vuletić, Tomislav ; Krča, Sanja ; Ivanković, Dušica ; Griparić, Lorena ; Podgornik, Rudi

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
The International Conference on Science and Technology of Synthetic Metals / Blau, Werner - Dublin : Trinity College Dublin, 2006

Skup
The International Conference on Science and Technology of Synthetic Metals

Mjesto i datum
Dublin, Irska, 02.07.2006. - 07.07.2006

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Nije recenziran

Ključne riječi
Dielectric spectroscopy; DNA dielectric relaxation; fundamental length scales

Sažetak
We demonstrate the power of low-frequency dielectric spectroscopy (40 Hz &#8211; 110 MHz) as an highly-sensitive and non-destructive technique to detect dispersion of DNA aqueous solutions and give information on the fundamental length scales that determine the structure of these solutions composed of many DNA polymers1. Results for polydisperse genomic Na-DNA (most of fragments with 20 kbp) reveal two broad relaxation modes of strength 20<&#61508; &#61541; LF<100 and 5<&#61508; &#61541; HF<20, centered at 0.5 kHz<&#61550; LF<70 kHz and 0.1 MHz<&#61550; HF<15 MHz2. We discuss possible assignments for these relaxation modes inside the framework of the standard double layer model for polarization response of charged biopolymers in solution3. The results show that there are three fundamental length scales that determine the dielectric response of a semidilute DNA solution, each of them following the power law behavior with a distinct exponent. These are the average separation between the polyelectrolyte chains, or equivalently the screening length of DNA acting as its own salt, the salt-dependent persistence length of a single polyelectrolyte chain and the mesh size of the polyelectrolyte solution. References: 1. F. Bordi, C. Cametti and R.H. Colby, J.Phys.: Condens. Matter 16, R1423 (2004). 2. S.Tomic et al., submitted to Phys.Rev.Lett. (February 2006). 3. A.V.Dobrynin and M.Rubinstein, Prog.Polym.Sci. 30, 1049 (2005) and A.V.Dobrynin, R.H.Colby and M.Rubinstein, Macromolecules 28, 1859 (1995).

Izvorni jezik
Engleski

Znanstvena područja
Fizika, Biologija

POVEZANOST RADA