Portal de Periódicos da CAPES

Artigo Produção Nacional Revisado por pares

BIBTEX RIS

Single-Step Purification of Recombinant Human Growth Hormone (hGH) Directly from Bacterial Osmotic Shock Fluids, for the Purpose of 125I-hGH Preparation

2000; Elsevier BV; Volume: 18; Issue: 2 Linguagem: Inglês

10.1006/prep.1999.1184

1096-0279

María Teresa, C. P. Ribela, Iara Maria Carneiro de Camargo, João Ezequiel Oliveira, Paolo Bartolini,

Radiopharmaceutical Chemistry and Applications

A good quality tracer, to be used in the radioimmunoassay of human growth hormone, was prepared by applying the chloramine-T iodination technique to the recombinant product obtained after a single-step high-performance size-exclusion chromatography purification of a bacterial osmotic shock fluid. The labeling reaction presented a yield of about 65% and the purified tracer exhibited an antibody binding of approximately 50% (NIDDK reference antiserum diluted 1:600,000). These values are very similar to those obtained by radioiodinating highly purified clinical-grade recombinant human growth hormone obtained from the same periplasmic extract after the regular six-step purification process. Both tracers provided the same accuracy, when evaluated with the use of commercial-quality control samples in a classical radioimmunoassay methodology, their stability being practically identical: about 18% decrease in antibody binding after 2 months of storage at -20 degrees C. The novel approach permits the utilization of transformed Escherichia coli strains as a source of freshly prepared, radioiodination-grade recombinant proteins, capable of providing better reproducibility and reagent continuity.