Molecular dynamics of aqueous solution of nonionic surfactant by broadband dielectric spectroscopy, dynamic light scattering, and PGSE-NMR

2013 ◽  
Author(s):  
T. Sawada ◽  
H. Saito ◽  
K. Maeda ◽  
R. Kita ◽  
N. Shinyashiki ◽  
...  
Author(s):  
Jorge Humberto Melillo ◽  
Jan Gabriel ◽  
Florian Pabst ◽  
Thomas Blochowicz ◽  
Silvina Cerveny

Characterizing the segmental dynamics of proteins, and intrinsically disordered proteins in particular, is a challenge in biophysics. In this study, by combining data from broadband dielectric spectroscopy (BDS) and both...


2007 ◽  
Vol 1019 ◽  
Author(s):  
Shyamal Kumar Kundu ◽  
Song Gi Choe ◽  
Wataru Yamamoto ◽  
Rio Kita ◽  
Shin Yagihara

AbstractThe dynamic light scattering (DLS) has been used to investigate the diffusion behavior and the size distribution of liposome. DLS experiments show two classes of particles with their hydrodynamic radii being 4-12 nm and 66-80 nm. The numbers of particles associated with the two peaks are estimated by means of the scattering properties of the particles, which show that the overwhelming majority is big ones.Broadband dielectric spectroscopy (BDS) has been used to investigate the dynamical structure of liposome in aqueous solution of water, which makes it possible to precisely explain the molecular mechanism, structures and various properties as a function of temperature and frequency. We have observed four relaxation processes, where two low frequency processes are commonly observed in charged macromolecules in aqueous solution, third process appeared in the MHz region due to the motion of ions, which is also related to the molecular motion of the lipid, and the high frequency process appeared about 20 GHz is due to free water surrounding liposome. Gel-LC phase transition has been described very accurately from the temperature-dependent shape parameter, β, obtained from the Cole-Cole fitting. The β value in LC phase is smaller than that in gel phase.


Polymers ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1355 ◽  
Author(s):  
Michelina Soccio ◽  
Daniel E. Martínez-Tong ◽  
Giulia Guidotti ◽  
Beatriz Robles-Hernández ◽  
Andrea Munari ◽  
...  

Poly(2,5-alkylene furanoate)s are bio-based, smart, and innovative polymers that are considered the most promising materials to replace oil-based plastics. These polymers can be synthesized using ecofriendly approaches, starting from renewable sources, and result into final products with properties comparable and even better than those presented by their terephthalic counterparts. In this work, we present the molecular dynamics of four 100% bio-based poly(alkylene 2,5-furanoate)s, using broadband dielectric spectroscopy measurements that covered a wide temperature and frequency range. We unveiled complex local relaxations, characterized by the simultaneous presence of two components, which were dependent on thermal treatment. The segmental relaxation showed relaxation times and strengths depending on the glycolic subunit length, which were furthermore confirmed by high-frequency experiments in the molten region of the polymers. Our results allowed determining structure–property relations that are able to provide further understanding about the excellent barrier properties of poly(alkylene 2,5-furanoate)s. In addition, we provide results of high industrial interest during polymer processing for possible industrial applications of poly(alkylene furanoate)s.


Polymer ◽  
2006 ◽  
Vol 47 (20) ◽  
pp. 7078-7084 ◽  
Author(s):  
Aurora Nogales ◽  
Alejandro Sanz ◽  
Tiberio A. Ezquerra ◽  
Robert Quintana ◽  
Sebastian Muñoz-Guerra

Polymer ◽  
2006 ◽  
Vol 47 (20) ◽  
pp. 7189-7197 ◽  
Author(s):  
Julius Tsuwi ◽  
Lutz Hartmann ◽  
Friedrich Kremer ◽  
Doris Pospiech ◽  
Dieter Jehnichen ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document