Human serum albumin as an intrinsic signal amplification amplifier for ultrasensitive assays of the prostate-specific antigen in human plasma.

As the most abundant protein in blood, human serum albumin (HSA) is usually regarded as an interferent in clinical molecular diagnosis. Herein, we report that HSA is an endogenous signal amplifier for the detection of the prostate-specific antigen (PSA) in human plasma. This is the first study to utilize intrinsic biological components as the signal amplifier in blood tests.