NMR relaxation of protons in tissues and other macromolecular water solutions

doi:10.1016/0730-725X(82)90172-2

Magnetic Resonance Imaging

Volume 1, Issue 4, 1982, Pages 209-226

https://doi.org/10.1016/0730-725X(82)90172-2 Get rights and content

Abstract

Nuclear magnetic resonance (NMR) longitudinal (T₁) and transverse (T₂) relaxation parameters have been evaluated for protein solutions, cellular suspensions and tissues using both data from our laboratory and the extensive literature. It is found that this data can be generalized and explained in terms of three water phases: free water, hydration water, and crystalline water. The proposed model which we refer to as the FPD model differs from similar models in that it assumes that free and hydration water are two phases with distinct relaxation times but that T₁ = T₂ in each phase. In addition there is a single correlation time for each rather than a distribution as assumed in most other models. Longitudinal decay is predicted to be single exponent in character resulting from a fast exchange between the free and hydration compartments. Transverse decay is predicted to be multiphasic with crystalline (T₂ ∼ 10 μsec), hydration (T₂ ∼ 10 sec) and free (T₂ ∼ 100 sec) water normally visible. The observed or effective transverse relaxation times for both the hydration and free water phases are greatly affected by the crystalline phase and are much shorter than the inherent relaxation times.

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Continuing educationNMR relaxation of protons in tissues and other macromolecular water solutions

Abstract

Biochim. Biophys. Acta

Biochim. Biophys. Acta

Biochim. Biophys. Acta

Biochim. Biophys. Acta

Cryobiol.

Biochim. Biophys. Acta

Biophys. J.

The principles of nuclear magnetism

Effects of temperature on water-microtuble interactions in a purified solution and in WI-38 cells

J. Cell Biol.

Microtubule complexes correlated with growth rate and water proton relaxation times in human breast cancer cells

Canc. Res.

Nuclear magnetic resonance patterns of intracellular water as a function of HeLa cell cycle

Science

Specific interactions of water with biopolymers

Relaxation effects in nuclear magnetic resonance absorption

Phys. Rev.

Nuclear magnetic resonance studies of living muscle

Science

Physical state of membrane constituents

Tumor detection by nuclear magnetic resonance

Science

Human tumors detected by nuclear magnetic resonance

Continuing education
NMR relaxation of protons in tissues and other macromolecular water solutions