L-(1-/sup 11/C)leucine: routine synthesis by enzymatic resolution
L-(1-/sup 11/C)leucine, suitable for the determination of cerebal protein synthesis rates in man using positron emission tomography, has been synthesized using a modified Bucherer-Strecker reaction sequence. The isolation of the pure L-amino acid isomer from the enantiomeric mixture, initially obtained using either an open or closed reaction vessel, was achieved using a D-amino acid oxidase/catalase enzyme complex immobilized on a Sepharose support. The O/sub 2/ required by the D-amino acid oxidase as the hydrogen acceptor was supplied by catalase. The L-(1-/sup 11/C)leucine was obtained with a radiochemical purity of >99% and with a radiochemical yield of 25%. Using a remote, semiautomated synthesis system, typical production time was 30 to 40 min after preparation of H/sup 11/CN. The use of immobilized enzymes for rapid and effective resolution of amino acid enantiomers eliminates the possibility of protein contamination and assures the production of a sterile, pyrogen-free product.
- Research Organization:
- Univ. of California, Los Angeles
- DOE Contract Number:
- AC03-76SF00012
- OSTI ID:
- 5748823
- Journal Information:
- J. Nucl. Med.; (United States), Journal Name: J. Nucl. Med.; (United States) Vol. 24:6; ISSN JNMEA
- Country of Publication:
- United States
- Language:
- English
Similar Records
Enzymatic syntheses of (1-(C-11))pyruvic acid and L-(1-(C-11))lactic acid via DL-(1-(C-11))alanine
Routine synthesis of carbon-11-carboxyl-labeled L-dopa
Related Subjects
400702* -- Radiochemistry & Nuclear Chemistry-- Properties of Radioactive Materials
550601 -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
ALKALINE HYDROLYSIS
AMINO ACIDS
BETA DECAY RADIOISOTOPES
BETA-PLUS DECAY RADIOISOTOPES
BIOSYNTHESIS
BODY
BRAIN
CARBON 11
CARBON ISOTOPES
CARBOXYLIC ACIDS
CENTRAL NERVOUS SYSTEM
CEREBRUM
CHEMICAL PREPARATION
CHEMICAL REACTIONS
COMPUTERIZED TOMOGRAPHY
DECOMPOSITION
DIAGNOSTIC TECHNIQUES
DRUGS
EMISSION COMPUTED TOMOGRAPHY
EVEN-ODD NUCLEI
HYDROLYSIS
IMMOBILIZED ENZYMES
ISOTOPES
LABELLED COMPOUNDS
LEUCINE
LIGHT NUCLEI
LYSIS
MINUTES LIVING RADIOISOTOPES
NERVOUS SYSTEM
NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANS
POSITRON COMPUTED TOMOGRAPHY
PROTEINS
RADIOISOTOPES
RADIOPHARMACEUTICALS
SOLVOLYSIS
SYNTHESIS
TOMOGRAPHY