Naslov
Fundamental length scales in Na-DNA solutions: semidilute versus dilute regime

Autori
Tomić, Silvia ; Dolanski Babić, Sanja ; Vuletić, Tomislva ; Ivek, Tomislav ; Krča, Sanja ; Griparić, Lorena ; Livolant, Francoise ; Podgornik, Rudi

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, pp prezentacija, znanstveni

Skup
II. Christmas Biophysics Workshop

Mjesto i datum
Bled, Slovenija, 18.12.2007. - 19.12.2007

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Nije recenziran

Ključne riječi
DNA dielectric relaxation ; fundamental length scales ; screening
(DNA dielectric relaxation ; fundamental length scales ; s)

Sažetak
A detailed characterization of complex dielectric response of Na-DNA aqueous solutions by means of dielectric spectroscopy in the frequency range 100 Hz – 100 MHz is presented. Two relaxation modes are revealed that can be attributed to diffusive motion of DNA counterions. The overall study in the wide concentration, added salt and chain length range demonstrates that the motion detected at lower frequencies probes single-chain structural properties, whereas the one at higher frequencies characterizes the collectives properties of the DNA solution composed of many chains. The characteristic length scales found in the measurements are compared with the fundamental length scales predicted by the theory. The issue of respective roles in ionic screening of intrinsic DNA counterions and added salt ions is also addressed with special emphasis on the controversial subject of DNA conformation in pure water solutions. At the end, open issues and prospects for further research are designated.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

POVEZANOST RADA