A method for measuring the apparent self-diffusion coefficient of in vivo lactic acid using double-quantum coherence-transfer spectroscopy

Abstract

Knowledge of the apparent self-diffusion coefficient of in vivo metabolites can potentially yield important information about the microenvironment of these compounds. The extent of molecular displacement by diffusion processes reflects the local temperature, mobility, and compartmentalization of the metabolite and may be useful in characterizing the disease state of a tissue or organ. The apparent self-diffusion coefficients of in viva 3’P metabolites have been studied using spin-echo NMR spectroscopy pulse sequences which contain diffusion-sensitive pulsed field gradients ( 1) , such as the Stejskal-Tanner sequence ( 2) in Fig. 1. Molecular diffusion in the presence of these gradient fields results in an attenuation of the echo signal amplitude given by