Biomaterial Database

7Li relaxation time measurements at very low magnetic field by 1H dynamic nuclear polarization. 2001

N Zeghib, and D Grucker

Institut de Physique Biologique, UPRES A 7004 du CNRS, IFR 37, Université Louis Pasteur, Strasbourg, France.

Dynamic nuclear polarization (DNP) of water protons was used to measure the relaxation time of lithium at very low magnetic field as a demonstration of the use of DNP for nuclei less abundant than water protons. Lithium (Li+) was chosen because it is an efficient treatment for manic-depressive illness, with an unknown action mechanism. After having recalled the theoretical basis of a three-spin system comprising two nuclei-the water proton of the solvent, the dissolved Li+ ion and the free electron of a free radical-we have developed a transient solution in order to optimize potential biological applications of Li DNP. The three-spin model has allowed computation of all the parameters of the system-the longitudinal relaxation rate per unit of free radical concentration, the dipolar and scalar part of the coupling between the nuclei and the electron. and the maximum signal enhancement achievable for both proton and lithium spins. All these measurements have been obtained solely through the detection of the proton resonance.

UI	MeSH Term	Description	Entries
D007554	Isotopes	Atomic species differing in mass number but having the same atomic number. (Grant & Hackh's Chemical Dictionary, 5th ed)	Isotope
D008094	Lithium	An element in the alkali metals family. It has the atomic symbol Li, atomic number 3, and atomic weight [6.938; 6.997]. Salts of lithium are used in treating BIPOLAR DISORDER.	Lithium-7,Lithium 7
D008280	Magnetics	The study of MAGNETIC PHENOMENA.	Magnetic
D011522	Protons	Stable elementary particles having the smallest known positive charge, found in the nuclei of all elements. The proton mass is less than that of a neutron. A proton is the nucleus of the light hydrogen atom, i.e., the hydrogen ion.	Hydrogen Ions,Hydrogen Ion,Ion, Hydrogen,Ions, Hydrogen,Proton
D005609	Free Radicals	Highly reactive molecules with an unsatisfied electron valence pair. Free radicals are produced in both normal and pathological processes. Free radicals include reactive oxygen and nitrogen species (RONS). They are proven or suspected agents of tissue damage in a wide variety of circumstances including radiation, damage from environment chemicals, and aging. Natural and pharmacological prevention of free radical damage is being actively investigated.	Free Radical
D013997	Time Factors	Elements of limited time intervals, contributing to particular results or situations.	Time Series,Factor, Time,Time Factor
D015233	Models, Statistical	Statistical formulations or analyses which, when applied to data and found to fit the data, are then used to verify the assumptions and parameters used in the analysis. Examples of statistical models are the linear model, binomial model, polynomial model, two-parameter model, etc.	Probabilistic Models,Statistical Models,Two-Parameter Models,Model, Statistical,Models, Binomial,Models, Polynomial,Statistical Model,Binomial Model,Binomial Models,Model, Binomial,Model, Polynomial,Model, Probabilistic,Model, Two-Parameter,Models, Probabilistic,Models, Two-Parameter,Polynomial Model,Polynomial Models,Probabilistic Model,Two Parameter Models,Two-Parameter Model