Performance characteristics of a cystatin C immunoassay with avian antibodies
2007 (English)In: Uppsala Journal of Medical Sciences, ISSN 0300-9734, E-ISSN 2000-1967, Vol. 112, no 1, 21-37 p.Article in journal (Refereed) Published
Background: A new particle-enhanced turbidimetric immunoassay (PETIA) with avian antibodies for measuring serum/plasma cystatin C has been developed. The performance characteristics of the assay are described. Methods: Measurements were performed on a Roche Modular P and on an Abbott Architect ci8200 using Gentian cystatin C immunoassay. Results: Measuring range was 0.3 - 8.0 mg/ L. Reference range was 0.57 - 1.09 mg/ L. Total analysis time was 10 minutes. Linearity was absolute over the whole assay range. Recovery of samples and controls was within 98.6 - 109.4%. Total imprecision CV, measured over 20days with two lots, was <= 4.2%. Comparision with a particle enhanced nephelometric cystatin C immunoassay (PENIA) by linear regression resulted in a slope within 0.97 - 1.02 and intercept within +/- 0.05 mg/ L. Interference studies with drugs, anticoagulants, intralipid (<= 11g/L), triglycerides (<= 14 g/L) and bilirubin (<= 420 mg/L) showed no significant interference. Due to the use of avain antibodies, no interference with rheumatoid factor was observed. No carry-over was detected. Lower detection limit and lower quantification limit (CV <= 6%) were both below 0.33 mg/L, which is less than the lowest standard. Sample stability was up to one month at 2 - 8 degrees C. Stability of the reagents at 2 - 8 degrees C was estimated to be 24 months. Stability of the reagents in use was minimum 9 weeks. Conclusions: Gentian cystatin C PETIA is shown to have excellent performance between methods. Interference results are improved due to avian antibodies and a broader span of the calibration curve. Avian antibodies are also known to have better immune response than mammalian antibodies towards mammalian antigens.
Place, publisher, year, edition, pages
2007. Vol. 112, no 1, 21-37 p.
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:uu:diva-152603ISI: 000253451900002OAI: oai:DiVA.org:uu-152603DiVA: diva2:413540