INVESTIGATION OF TEMPERATURE DEPENDENCE OF D2O SOLUTIONS BY 400 MHZ NMR

Authors : Gülten KAVAK BALCI, Canan AYTUĞ AVA, Ali YILMAZ

Pages : 1-6

Doi:10.23884/mejs.2018.4.1.01

View : 13 | Download : 5

Publication Date : 2018-06-04

Article Type : Research Paper

Abstract :The rate of water proton relaxation of protein solutions were studied in the presence and absence of the paramagnetic ions[ gadolinium insert ignore into journalissuearticles values(III);, manganese insert ignore into journalissuearticles values(II);, chromium insert ignore into journalissuearticles values(III);, iron insert ignore into journalissuearticles values(III);, nickel insert ignore into journalissuearticles values(II);, copper insert ignore into journalissuearticles values(II);, and cobalt insert ignore into journalissuearticles values(II);]   in the previous studies. However, these studies were carried out rather at low frequencies. Therefore, studying of temperature dependence of relaxation rates for absence and presence of 2 % albumin in pure D 2 O by 400 MHz will be a novelty. In this study, T 1 and T 2 relaxation ratios of D 2 O and 0.1 H 2 O / 0.9D 2 O solutions were investigated with respect to temperature for pure and  for constant  albumin  concentrationinsert ignore into journalissuearticles values(2%);. The experiments were carried out by using Bruker Avance 400 MHz NMR. Inversion Recovery insert ignore into journalissuearticles values(180-τ-90); pulse step were used for T 1 , whereas Carr-Purcell-Meiboom-Gill pulse step were used for T 2 .  The experiments were performed for temperature range of 20°C-40°C by using automatic temperature control unit. 1/T 1 and 1/T 2 decrease linearly with increasing temperature for pure D 2 O solutions. However, for 0.1H 2 O/0.9D 2 O solutions, the relaxation rates of T 1 increase with increasing temperature while T 2 decreases with increasing temperature. The decrease in both relaxation rates of the D 2 O solution with respect to the increased temperature suggests that relaxation is due to spin relaxation interaction. Increasing of relaxation rates with the increasing temperature, in the presence of albumin demonstrates the validity of the dipolar mechanism
Keywords : NMR, T1, T2, Relaxation, Albumin