Abstract
Background. A competitive solid-phase assay for the measurement of gastrin in serum using time-resolved fluorescence was developed as an alternative to conventional radioimmunoassay (RIA) technology. Methods. The assay depends on the competitive binding of unlabelled versus Eu-labelled gastrin to specific gastrin antibodies - bound to anti-rabbit IgG immobilized on polystyrene microtitration strips. The bound Eu3+-label was dissociated from the bound gastrin and converted to a fluorescent β-diketone chelate which was measured by fluorometry with time-resolution. Results. Using a sample volume of 50 μl the lower limit of detection was below10 pmol/L. Dilution of samples showed an excellent linearity. Spiking with gastrin-17 in known concentrations showed a recovery of 103% indicating that there is no bias inherent in the assay. The method correlated fully with the routine in-house radioimmunoassay in the concentration range 10-400 pmol/L (slope = 0.98 with r2 = 0.98). Thus the reference interval for clinical samples does not require modification when changing from one method to the other. Conclusion. We have described a convenient and accurate competitive assay for measurement of gastrin in serum based on solid-phase technology using time-resolved fluorometric detection as a realistic alternative to the established state-of-the-art RIA-technology.
| Originalsprog | Engelsk |
|---|---|
| Tidsskrift | Scandinavian Journal of Clinical & Laboratory Investigation |
| Vol/bind | 71 |
| Udgave nummer | 3 |
| Sider (fra-til) | 216-20 |
| Antal sider | 5 |
| ISSN | 0036-5513 |
| DOI | |
| Status | Udgivet - maj 2011 |