Molecular velocity auto-correlations in glycerol/water mixtures studied by NMR MGSE method

Stepišnik, Janez (avtor), Mattea, Carlos (avtor), Stapf, Siegfried (avtor), Mohorič, Aleš (avtor)

Molecular dynamics in binary mixtures of water and glycerol was studied by measuring the spectrum of water velocity auto-correlation in the frequency range from 0.05 − 10 kHz by using the NMR method of modulated gradient spin echo. The method shows that the diversity of diffusion signature in the short spin trajectories provides information about heterogeneity of molecular motion due to the motion in the micro-vortexes of hydrodynamic fluctuation, which is especially pronounced for the mixtures with low glycerol content. As concentration of glycerol increases above 10vol%, a new feature of spectrum appears due to interaction of water molecules with the clusters formed around hydrophilic glycerol molecules. New spectrum exposes a rate thickening of molecular friction, according to Einstein–Smoluchowski–Kubo formula, which inhibits rapid molecular motions and creates the conditions for a slow process of spontaneously folding of disordered poly-peptides into biologically active protein molecules when immersed in such a mixture.

• Jezik: Angleški jezik
• Ključne besede: molecular dynamics, nuclear magnetic resonance, MGSE method, glycerol/water mixture, NMR, gradient spin-echo, self-diffusion, molecular velocity auto-correlation, shear rate viscosity thickening, protein folding
• Vrsta gradiva: Članek v reviji
• Tipologija: 1.01 - Izvirni znanstveni članek
• Organizacija: FMF - Fakulteta za matematiko in fiziko
• Status publikacije: Objavljeno
• Različica publikacije: Objavljena publikacija
• Leto izida: 2020
• Št. strani: 12 str.
• Številčenje: Vol. 553, art. 124171
• PID: 20.500.12556/RUL-137731
• UDK: 543.429.23
• ISSN pri članku: 0378-4371
• DOI: 10.1016/j.physa.2020.124171
• COBISS.SI-ID: 19363843
• Datum objave v RUL: 29.06.2022

Gradivo je del revije

• Naslov: Physica. A, Statistical mechanics and its applications
• Skrajšan naslov: Physica, A
• Založnik: Elsevier
• ISSN: 0378-4371
• COBISS.SI-ID: 3270415

Licence

• Licenca: CC BY-NC-ND 4.0, Creative Commons Priznanje avtorstva-Nekomercialno-Brez predelav 4.0 Mednarodna
• Povezava: http://creativecommons.org/licenses/by-nc-nd/4.0/deed.sl
• Opis: Najbolj omejujoča licenca Creative Commons. Uporabniki lahko prenesejo in delijo delo v nekomercialne namene in ga ne smejo uporabiti za nobene druge namene.

Sekundarni jezik

• Jezik: Slovenski jezik
• Ključne besede: molekulska dinamika, jedrska magnetna resonanca, metoda MGSE

Projekti

• Financer: ARRS - Agencija za raziskovalno dejavnost Republike Slovenije
• Številka projekta: P1-0060
• Naslov: Eksperimentalna biofizika kompleksnih sistemov in slikanje v biomedicini