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- Titel:
Immunoassay for sex hormone-binding globulin in undiluted serum is influenced by high-molecular-mass aggregates.
- Dokumenttyp:
- Journal Article; Article
- Autor(en):
- Thaler, M; Metzger, J; Schreiegg, A; Denk, B; Gleixner, A; Hauptmann, H; Luppa, PB
- Abstract:
- BACKGROUND: The new Elecsys chemiluminescence assay for measurement of homodimeric sex hormone-binding globulin (SHBG) was designed for use with undiluted serum, in contrast to other methods that require predilution. During assay development, unexpected calibration difficulties were observed that were attributable to particular biochemical properties of the highly concentrated SHBG in solution. METHODS: We used a surface plasmon resonance (SPR) biosensor, which enables biomolecular interaction analysis of SHBG, and size-exclusion chromatography for this investigation. The immunoassay was evaluated for imprecision, linearity, and suitability of the dilution medium, and the method was compared with an IRMA for SHBG. RESULTS: The SPR biosensor characterized the special protein properties of SHBG in various concentrations. Above 200 nmol/L there was a strong tendency toward formation of high-molecular-mass aggregates. This was also detectable by size-exclusion chromatography and could be reversed by simple dilution of the sample. On the basis of these results, the dynamic measuring range of the SHBG assay is restricted to 0.350-200 nmol/L. Assay evaluation on a 2010 analyzer revealed excellent precision (CV
- Zeitschriftentitel:
- Clin Chem
- Jahr:
- 2005
- Band / Volume:
- 51
- Heft / Issue:
- 2
- Seitenangaben Beitrag:
- 401-7
- Sprache:
- eng
- Volltext / DOI:
- doi:10.1373/clinchem.2004.034264
- PubMed:
- http://view.ncbi.nlm.nih.gov/pubmed/15590752
- Print-ISSN:
- 0009-9147
- TUM Einrichtung:
- Institut für Klinische Chemie und Pathobiochemie
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