Radioactive iodine exchange reaction of HIPDM: kinetics and mechanism

Journal Article · Sun Mar 01 00:00:00 EST 1987 · J. Nucl. Med.; (United States)

OSTI ID:6862914

Lui, B; Chang, J; Sun, J S; Billings, J; Steves, A; Ackerhalt, R; Molnar, M; Kung, H F

In conjunction with single photon emission computed tomography (SPECT), iodine-123 (/sup 123/I)-labeled N,N,N'-trimethyl-(2-hydroxy-3-methyl-5-iodobenzyl)-1,3-propanediamine (HIPDM) has been used clinically as a regional cerebral perfusion imaging agent. The (/sup 123/I)HIPDM can be prepared by a simple aqueous exchange reaction in a kit form. We synthesized unlabeled HIPDM by condensation of 2-hydroxy-3-methyl-5-iodobezaldehyde and N,N,N'-trimethyl-1,3-propanediamine, followed by a sodium borohydride reduction reaction. The kinetics of the radioactive iodine exchange reaction for the preparation of (/sup 123/I)HIDM is controlled by the pH, the temperature, and the presence of reductant (sodium bisulfite), and oxidant (sodium iodate). The reaction is a second order iodine-iodine exchange with an activation energy of 30.6 kcal/mole. The mechanism of this reaction probably involves the formation of an active 1+ or iodine free radical, which is sensitive to the presence of a reductant, such as sodium bisulfite.

• Research Organization: Beijing Normal Univ., China
• OSTI ID: 6862914
• Journal Information: J. Nucl. Med.; (United States), Vol. 3
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
RADIOPHARMACEUTICALS
CHEMICAL PREPARATION
BIOCHEMICAL REACTION KINETICS
BRAIN
IN VITRO
BODY
CENTRAL NERVOUS SYSTEM
DRUGS
KINETICS
LABELLED COMPOUNDS
NERVOUS SYSTEM
ORGANS
REACTION KINETICS
SYNTHESIS
550601* - Medicine- Unsealed Radionuclides in Diagnostics
400702 - Radiochemistry & Nuclear Chemistry- Properties of Radioactive Materials