a three-hour radioimmunoassay ( ria ) for serum hcg with a sensitivity of 5 mlu/ml was developed which utilizes an antiserum generated against the beta subunit of hcg , 125i-hcg for tracer purposes , a highly purified hcg standard , and dioxane for separation of bound from free hormone .
C0106132
beta subunit
C0018062
hcg