Highly sensitive immunological assays for human chorionic gonadotrophin and prostatic acid phosphatase using phenacyl phosphate as a chemiluminescent label

A highly sensitive assay for alkaline phosphatase (ALP) was developed using phenacyl phosphate as a substrate for chemiluminescent assays. This substrate is applied to two types of immunological assays based on ALP labelling, an assay for human chorionic gonadotrophin (hCG) in urine by a two-site immunometric assay and an assay for human prostatic acid phosphatase (PAP) adsorbed on a solid phase by an antibody. The results of the validation on these assays were good and detection limits were 15–40 times better than for conventional assays, viz. 6.25 × 10−6 IU for hCG and 1.25 × 10−18 mol PAP.