Influence of Assay Methodology on the Measurement of Free Serum Ceftriaxone Concentrations
AUTOR(ES)
Kohlhepp, Sue J.
FONTE
American Society for Microbiology
RESUMO
The influence of assay methodology on the measurement of the active free fraction of ceftriaxone in plasma was determined. The free fraction was measured by three methods: agar diffusion bioassay, precipitation of plasma protein with methanol followed by high-performance liquid chromatography (HPLC) of the supernatant, and ultrafiltration of plasma followed by HPLC of the filtrate. In human serum, the free ceftriaxone levels were significantly lower (P = 0.03) when measured on ultrafiltrates compared to the other two methods. This difference disappeared when dolphin serum was studied. After ultrafiltration, human serum was shown, by Scatchard plot analysis, to have two ceftriaxone binding sites. Species differences were also demonstrated. Hence, in humans, determination of free plasma ceftriaxone varies with the assay method employed.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=105804Documentos Relacionados
- Comparison of a radioimmunoassay and a microbiological assay for measurement of serum vancomycin concentrations.
- Influence of normal human serum on the determination of trichomonicidal drug concentrations.
- Measurement of concentrations of human serum immunoglobulins.
- Influence of temperature on degradation kinetics of ceftriaxone in diluted and undiluted human serum.
- The influence of penicillin on Lactobacillus leichmannii serum B12 assay