ULTRAMICROELISA FOR DETECTION AND QUANTIFICATION OF HUMAN CHORIONIC-GONADOTROPIN IN URINE AND SERUM

We developed a noncompetitive immunoassay for intact human chorionic g onadotropin (Ultramicro-ELISA-HCG, 10 mu L of samples and reagents) co mpatible with SUMA (Ultramicroanalytical system) technology designed m ainly for screening purposes, We designed two types of assay-one quali tative for urine samples and the other quantitative for serum, with an effective working range from 25 to 400 mIU/mL. The working time was o ne and one-half hours, The calculations and interpretation of the resu lts were done automatically by SUMA equipment, In the quantitative ass ay we found inter- and intrassay coefficient of variation below 10%, a nalytical recovery ranging from 98 to 120%, and good parallelism, The assay for urine was clinically validated using samples from abortion s ervices, resulting in a 100% sensitivity and specificity, We establish ed a 50 mIU/mL cutoff as a criterion for pregnancy.