title: Interlaboratory study comparing the microbiological potency of spiramycins I, II and III.
abstract: An interlaboratory study has been performed to determine the relative potencies of spiramycins (SPMs) I, II and III by diffusion or/and turbidimetric assays with Bacillus subtilis or Staphylococcus aureus as the test organisms. Six laboratories from three countries participated. Experimental procedures were according to the European Pharmacopoeia, 3rd ed. The activity of SPM I is markedly higher than that of SPM II and III. By diffusion, the activities of SPM II and III relative to SPM I were found to be 57 and 72%, respectively. The interlaboratory relative standard deviations (RSD) varied from 3.6 to 16.3%. By turbidimetry, the activities of SPM II and III relative to SPM I were found to be 45 and 52%, respectively. The interlaboratory RSD values varied from 2.6 to 7.7%. The results of the study were analyzed according to the ISO 5725-2 guidelines to determine the repeatability, the between-laboratory and the reproducibility variances of both methods.
authors.affiliation: Laboratorium voor Farmaceutische Chemie en Analyse van Geneesmiddelen, Faculteit Farmaceutische Wetenschappen, Katholieke Universiteit Leuven, Belgium.
authors.forename: L
authors.initials: L
authors.lastname: Liu
authors.forename: J
authors.initials: J
authors.lastname: Saevels
authors.forename: P
authors.initials: P
authors.lastname: Louis
authors.forename: H
authors.initials: H
authors.lastname: Nelis
authors.forename: S
authors.initials: S
authors.lastname: Rico
authors.forename: K
authors.initials: K
authors.lastname: Dierick
authors.forename: S
authors.initials: S
authors.lastname: Guyomard
authors.forename: E
authors.initials: E
authors.lastname: Roets
authors.forename: J
authors.initials: J
authors.lastname: Hoogmartens
mesh_terms: D000617:Aminoglycosides; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001412:Bacillus subtilis / Q000187:drug effects; D001681:Biological Assay; D003470:Culture Media; D004058:Diffusion; D008826:Microbial Sensitivity Tests; D009391:Nephelometry and Turbidimetry; D012015:Reference Standards; D015203:Reproducibility of Results; D015572:Spiramycin / Q000031:analogs & derivatives* / Q000494:pharmacology; D013211:Staphylococcus aureus / Q000187:drug effects
chemical_list: D000617:Aminoglycosides; D000900:Anti-Bacterial Agents; D003470:Culture Media; C017186:demycarosylturimycin H; C033163:acetylspiramycin; C087816:spiramycin III; D015572:Spiramycin