Preparation of iodine-125-labeled insulin for radioimmunoassay: comparison of lactoperoxidase and chloramine-T iodination. 1978

B L Wajchenberg, and H Pinto, and I Torres de Toledo e Souza, and A C Lerário, and R Ribeiro Pieroni

The enzymatic radioiodination of porcine insulin by a system consisting of lactoperoxidase, hydrogen peroxide, and Na125I was compared with a modified chloramine-T technique. Satisfactory specific activity of the labeled hormone was obtained with the enzymatic iodination, with much greater immunoreactivity and stability than after chloramine-T, besides being quite suitable for the measurement of low plasma insulin levels. There was a positive and highly significant correlation between the insulin concentrations measured with the two tracers, with the regression line defined by the equation: y (chloramine-T) = 8.34 + 0.99 x (lactoperoxidase).

UI MeSH Term Description Entries
D007202 Indicators and Reagents Substances used for the detection, identification, analysis, etc. of chemical, biological, or pathologic processes or conditions. Indicators are substances that change in physical appearance, e.g., color, at or approaching the endpoint of a chemical titration, e.g., on the passage between acidity and alkalinity. Reagents are substances used for the detection or determination of another substance by chemical or microscopical means, especially analysis. Types of reagents are precipitants, solvents, oxidizers, reducers, fluxes, and colorimetric reagents. (From Grant & Hackh's Chemical Dictionary, 5th ed, p301, p499) Indicator,Reagent,Reagents,Indicators,Reagents and Indicators
D007328 Insulin A 51-amino acid pancreatic hormone that plays a major role in the regulation of glucose metabolism, directly by suppressing endogenous glucose production (GLYCOGENOLYSIS; GLUCONEOGENESIS) and indirectly by suppressing GLUCAGON secretion and LIPOLYSIS. Native insulin is a globular protein comprised of a zinc-coordinated hexamer. Each insulin monomer containing two chains, A (21 residues) and B (30 residues), linked by two disulfide bonds. Insulin is used as a drug to control insulin-dependent diabetes mellitus (DIABETES MELLITUS, TYPE 1). Iletin,Insulin A Chain,Insulin B Chain,Insulin, Regular,Novolin,Sodium Insulin,Soluble Insulin,Chain, Insulin B,Insulin, Sodium,Insulin, Soluble,Regular Insulin
D007457 Iodine Radioisotopes Unstable isotopes of iodine that decay or disintegrate emitting radiation. I atoms with atomic weights 117-139, except I 127, are radioactive iodine isotopes. Radioisotopes, Iodine
D007553 Isotope Labeling Techniques for labeling a substance with a stable or radioactive isotope. It is not used for articles involving labeled substances unless the methods of labeling are substantively discussed. Tracers that may be labeled include chemical substances, cells, or microorganisms. Isotope Labeling, Stable,Isotope-Coded Affinity Tagging,Isotopically-Coded Affinity Tagging,Affinity Tagging, Isotope-Coded,Affinity Tagging, Isotopically-Coded,Isotope Coded Affinity Tagging,Labeling, Isotope,Labeling, Stable Isotope,Stable Isotope Labeling,Tagging, Isotope-Coded Affinity,Tagging, Isotopically-Coded Affinity
D007784 Lactoperoxidase An enzyme derived from cow's milk. It catalyzes the radioiodination of tyrosine and its derivatives and of peptides containing tyrosine.
D010544 Peroxidases Ovoperoxidase
D011863 Radioimmunoassay Classic quantitative assay for detection of antigen-antibody reactions using a radioactively labeled substance (radioligand) either directly or indirectly to measure the binding of the unlabeled substance to a specific antibody or other receptor system. Non-immunogenic substances (e.g., haptens) can be measured if coupled to larger carrier proteins (e.g., bovine gamma-globulin or human serum albumin) capable of inducing antibody formation. Radioimmunoassays
D002700 Chloramines Inorganic derivatives of ammonia by substitution of one or more hydrogen atoms with chlorine atoms or organic compounds with the general formulas R2NCl and RNCl2 (where R is an organic group). Chloroamines
D006801 Humans Members of the species Homo sapiens. Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D006861 Hydrogen Peroxide A strong oxidizing agent used in aqueous solution as a ripening agent, bleach, and topical anti-infective. It is relatively unstable and solutions deteriorate over time unless stabilized by the addition of acetanilide or similar organic materials. Hydrogen Peroxide (H2O2),Hydroperoxide,Oxydol,Perhydrol,Superoxol,Peroxide, Hydrogen

Related Publications

B L Wajchenberg, and H Pinto, and I Torres de Toledo e Souza, and A C Lerário, and R Ribeiro Pieroni
July 1978, Journal of endocrinological investigation,
B L Wajchenberg, and H Pinto, and I Torres de Toledo e Souza, and A C Lerário, and R Ribeiro Pieroni
January 1984, Journal of immunoassay,
B L Wajchenberg, and H Pinto, and I Torres de Toledo e Souza, and A C Lerário, and R Ribeiro Pieroni
May 1977, Immunochemistry,
B L Wajchenberg, and H Pinto, and I Torres de Toledo e Souza, and A C Lerário, and R Ribeiro Pieroni
December 1985, Endocrinologia experimentalis,
B L Wajchenberg, and H Pinto, and I Torres de Toledo e Souza, and A C Lerário, and R Ribeiro Pieroni
January 1976, Biochemical and biophysical research communications,
B L Wajchenberg, and H Pinto, and I Torres de Toledo e Souza, and A C Lerário, and R Ribeiro Pieroni
November 1977, Hoppe-Seyler's Zeitschrift fur physiologische Chemie,
B L Wajchenberg, and H Pinto, and I Torres de Toledo e Souza, and A C Lerário, and R Ribeiro Pieroni
May 1982, Thrombosis research,
B L Wajchenberg, and H Pinto, and I Torres de Toledo e Souza, and A C Lerário, and R Ribeiro Pieroni
May 1979, European journal of biochemistry,
B L Wajchenberg, and H Pinto, and I Torres de Toledo e Souza, and A C Lerário, and R Ribeiro Pieroni
September 1976, Journal of nuclear medicine : official publication, Society of Nuclear Medicine,
B L Wajchenberg, and H Pinto, and I Torres de Toledo e Souza, and A C Lerário, and R Ribeiro Pieroni
August 1972, Journal of nuclear medicine : official publication, Society of Nuclear Medicine,
Copied contents to your clipboard!