Abstract: DEVELOPMENT OF RADIOIMMUNOASSAY KIT FOR HUMAN PLACENTAL LACTOGEN IN SERUMHou Huiren Su Jingxian Zhou Ling(Department of Isotope, China Institute of Atomic Energy, Beijing 102413)ABSTRACTThe HPL radioimmunoassay kit provides a rapid and sensitive determination of HPL by direct RIA of serum samples. The standard or serum patient，s circulating HPL competes with the radioactive tracer for the binding sites of HPLspecfic antibody. The standard range is 0.1-10.0 mg/L and the recovery is within 92.7%-106.3%. The intra and inter assay coefficient of variation are 3.4%-3.8% and 9.2%-10.6%,respectively.The analytical sensitivity (lowest detectable dose) is 0.005 mg/L， maximum binding is approximately 30%-70%. The immuno complex formed during the period of 30 minutes incubation is separated from the free HPL by centrifugation.Key words HPL RIA kit