One-step quantitative thyrotropin assay for the detection of hypothyroidism in point-of-care conditions.
OBJECTIVE
Different screening strategies for early diagnosis of hypothyroidism have been discussed increasingly. We demonstrate the applicability of a miniaturized microparticle assay format for rapid and quantitative determination of increased thyrotropin (TSH) concentrations in serum.


METHODS
Porous microparticles were used as solid phase for a noncompetitive, one-step, kinetic immunoassay with varying incubation times and time-resolved fluorescence detection.


RESULTS
The analytical (mean of zero + 3 SD) and functional (CV <15%) detection limits were 1.5 and 6.0 mIU/L for 2-min, 0.5 and 1.5 mIU/L for 7-min, and 0.2 and 0.5 mIU/L for 15-min assays, respectively. A good correlation was found with the Chiron Diagnostics ACS:180 assay (slopes 0.885-1.051, y-intercepts < +/- 0.20 mIU/L, S(y logical or, bar below x) <or= 0.10 mIU/L, r > 0.98, n = 20).


CONCLUSIONS
The kinetic TSH assay provides reproducible and quantitative information on thyroid status within minutes and is applicable for the detection of hypothyroidism in point-of-care (POC) conditions.
von Lode
Piia
P
Department of Biotechnology, University of Turku, Tykistökatu 6A, FIN-20520, Turku, Finland. pimeta@utu.fi
Hagrén
Virve
V
Palenius
Tom
T
Lövgren
Timo
T
D002138:Calibration; D016231:Fluorescence Polarization Immunoassay / Q000379:methods / Q000592:standards; D006801:Humans; D007037:Hypothyroidism / Q000097:blood* / Q000175:diagnosis; D007700:Kinetics; D016014:Linear Models; D010316:Particle Size; D019095:Point-of-Care Systems; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013223:Statistics as Topic; D013972:Thyrotropin / Q000097:blood*
D013972:Thyrotropin