RESUMEN
Tests in five laboratories on pooled sera in three concentration ranges demonstrated good reproducibility of urea concentration with the Reflotest-Urea, at a variation coefficient from 2.4% to 5.0%. Comparison with the urease/GLDH, Berthelot and diacetylmonoxim tests on sera from routine samples indicated good agreement of results even for pathological samples. Using whole blood there was also good agreement with results with plasma of the same samples. The Reflotest-Urea method is simple because different dose ranges can be used and the reaction time of ten minutes is not crucial. In-vitro studies using 37 of the most commonly used drugs in different areas of medicine failed to reveal any interference with the test.
Asunto(s)
Indicadores y Reactivos , Tiras Reactivas , Urea/sangre , Análisis de Varianza , Humanos , Métodos , Factores de TiempoRESUMEN
This paper summarises the results of the evaluation of a heterologous enzyme immunoassay in antibody coated tubes for the determination of triiodothyronine (T3) by a group of 11 laboratories. The assay procedure is analogous to an established heterologous thyroxine enzyme immunoassay. The evaluation demonstrated that 1. the specificity of the assay and its analytical range between 0.46 and 9.2 nmol/l meet diagnostic requirements, 2. the intra- and interassay precision was in accordance with that commonly found in radio immunoassays, 3. the recovery of added T3 was between 90 and 103%, 4. the results agreed well with those of self-established radio immunoassays and were comparable with commercial RIA kits, 5. there was no interference by hyperbilirubinaemia or by high concentrations of bile acids, but interference can occur in very haemolytic and lipaemic samples. The great advantage of T3 enzyme immunoassays lies in the absence of restrictions and any authorization needed for working with radioactive substances.