15N-labed glycine synthesis

Abstract

This work describes a method for 15 N-isotope-labeled glycine synthesis, as well as details about a recovery line for nitrogen residues. To that effect, amination of α-haloacids was performed, using carboxylic chloroacetic acid and labeled aqueous ammonia ( 15 NH 3 ). Special care was taken to avoid possible 15 NH 3 losses, since its production cost is high. In that respect, although the purchase cost of the 13 N-labeled compound (radioactive) is lower, the stable tracer produced constitutes an important tool for N cycling studies in living organisms, also minimizing labor and environmental hazards, as well as time limitation problems in field studies. The tests were carried out with three replications, and variable 15 NH 3 (aq) volumes in the reaction were used (50, 100, and 150 mL), in order to calibrate the best operational condition; glycine masses obtained were 1.7, 2, and 3.2 g, respectively. With the development of a system for 15 NH 3 recovery, it was possible to recover 71, 83, and 87% of the ammonia initially used in the synthesis. With the required adaptations, the same system was used to recover methanol, and 75% of the methanol initially used in the amino acid purification process were recovered.

Síntese e controle de qualidade da ureia enriquecida em 13C para diagnóstico da Helicobacterpylori (HP)

“…19 A disponibilidade de compostos enriquecidos nos isótopos estáveis ( 15 N, 34 S, entre outros), no país, impulsionou significativamente as pesquisas com o emprego de traçador não radioativo. [20][21][22][23] Ressalta-se, ainda, que os custos desses compostos têm se mostrado inferiores ao preço de comercialização internacional (FOB).…”

Production of 15N-enriched nitric acid (H15NO3)

“…In this respect, some studies have been developed in Brazil Bendassolli et al, 2002;Bendassolli et al, 1988;Bendassolli et al, 1989;Bendassolli, 1991;Tavares et al, 2006;Maximo et al, 2005;Oliveira, 2000;Tavares, 2005 …”