EVALUATION OF INNOFLUOR FLUORESCENCE POLARIZATION IMMUNOASSAY KITS FOR THE DETERMINATION OF SERUM CONCENTRATIONS OF GENTAMICIN, TOBRAMYCIN,AMIKACIN AND VANCOMYCIN

The Innofluor fluorescence polarization immunoassay (FPIA) kits for ge ntamicin, tobramycin, amikacin and vancomycin were evaluated on an Abb ott TDX analyser. Intra-assay reproducibility was excellent with a coe fficient of variation of <3% for all analytes. The coefficient of vari ation for inter-assay reproducibility was usually <5%. Assay linearity was good and standard curve stability was seen with kits of the same batch for at least 32 days. Using clinical samples, the results obtain ed with the Innofluor FPIA reagents correlated well with those obtaine d using Abbott FPIA reagents, but Innofluor gentamicin and amikacin re sults were slightly higher than Abbott results (P < 0.001). Results of UK NEQAS returns showed acceptable accuracy for the Innofluor kits, b ut mean Innofluor gentamicin returns were 4% higher (P = 0.001) and me an vancomycin returns were 5% lower (P = 0.001) than overall mean retu rns. Innofluor and Abbott vancomycin assay reagents showed similar cro ss-reactivity to degraded vancomycin.