title: Multi-site analytical evaluation of a chemiluminescent magnetic microparticle immunoassay (CMIA) for sirolimus on the Abbott ARCHITECT analyzer.
abstract: OBJECTIVE
  This study evaluated a new chemiluminescent magnetic microparticle immunoassay (CMIA) for sirolimus on the ARCHITECT analyzer.
  
  
  METHODS
  Patient and laboratory proficiency samples were tested at three European sites and one site in the United States.
  
  
  RESULTS
  The CMIA total %CV's were all <8% and the Limit of Quantification (LOQ) was <1.52 ng/mL across the four sites. It cross-reacts to sirolimus metabolites F4 and F5 and showed no hematocrit interference over a range of 25% to 55%. Patient specimen correlations to three LC/MS/MS methods gave R>or=0.91 at three sites and mean biases of 14%, 25% and 39%. CMIA patient specimen correlations to the Abbott IMx gave R>or=0.94 at 2 sites and mean biases of 5.4% and 6.9%.
  
  
  CONCLUSIONS
  CMIA is a precise and sensitive immunoassay method without hematocrit interference. It correlates well to both LC/MS/MS and immunoassay results, but shows an expected positive bias to LC/MS/MS.
authors: Medical University Vienna, Vienna, Austria.
authors: Rainer W
authors: RW
authors: Schmid
authors: Johannes
authors: J
authors: Lotz
authors: Rosemarie
authors: R
authors: Schweigert
authors: Karl
authors: K
authors: Lackner
authors: Giuseppe
authors: G
authors: Aimo
authors: Judith
authors: J
authors: Friese
authors: Thomas
authors: T
authors: Rosiere
authors: Diana
authors: D
authors: Dickson
authors: Daniel
authors: D
authors: Kenney
authors: Gregory T
authors: GT
authors: Maine
mesh_terms: D000918:Antibody Specificity; D002853:Chromatography, Liquid / Q000379:methods; D006801:Humans; D007118:Immunoassay / Q000295:instrumentation / Q000379:methods*; D007166:Immunosuppressive Agents / Q000097:blood*; D008163:Luminescent Measurements / Q000295:instrumentation / Q000379:methods*; D008280:Magnetics; D010316:Particle Size; D012680:Sensitivity and Specificity; D020123:Sirolimus / Q000097:blood*; D053719:Tandem Mass Spectrometry / Q000379:methods
chemical_list: D007166:Immunosuppressive Agents; D020123:Sirolimus