Measurement of Acid-Base Neutralisation Reactions by Magnetic Resonance Imaging

Stephen Evans and Laurie Hall

Herchel Smith Laboratory for Medicinal Chemistry,

University of Cambridge School of Clinical Medicine, Forvie Site, Robinson Way Cambridge CB2 2PZ, UK, Tel: +44(0)1223 336805/336807 Fax: +44(0)1223 336748

Email: 1dh11@hslmc.cam.ac.uk Website: www.hslmc.cam.ac.uk

ABSTRACT

Magnetic Resonance Imaging (MRI) has been used to measure the nuclear relaxation times of the protons of water containing low concentrations of the diethylenetriaminepentaaceticacid complex of manganese (DTPA). Given that the manganese-binding equilibrium is dependent on the local pH this forms the basis of a non-invasive method for quantitation of pH in three dimensions. The basic concepts are briefly described along with details of the pickling of onion.

Keywords MRI, pH measurement, pickling