Solid-Phase Enzymoimmunoassayof Estrone in Saliva

In this solid-phaseenzymoimmunoassayfor estrone in sali-va, microtiterplates are used after extractionof the sample withdiethylether. No chromatographicstep is involved.The detection limit of the assay is 450 fg per well (33 pmol/L). Intra-and interassaycoefficientsof variationfor the assay of low, medium, and high concentrations of estrone in saliva were respectively 4.2, 12.7; 5.2, 8.7; and 2.7, 5.8%. Using this assay, we found a highly significant correlation (P <0.001) between estrone concentrationsin time-matched serumand salivasamples.The analyticalprocedureis rapid and relativelysimple. One person can assay 50-60 saliva samplesdunnga normalworkingday. We concludethat the assay is very suitable, even in small laboratories,for saliva estronemeasurements,which, in facilitatingserialsampling, enablesdynamicobservationsof estroneconcentrationsan