Surface plasmon fluorescence immunoassay of free prostate-specific antigen in human plasma at the femtomolar level.
This study describes the development of a surface plasmon fluorescence spectroscopy (SPFS)-based sandwich immunoassay, for the detection of free prostate-specific antigen (f-PSA). The commercial CM5 chip (Biacore) was integrated into the SPFS-based assay making use of its three-dimensionally extended dextran architecture, which offers a large protein retention capacity and alleviates the metal-induced fluorescence quenching. The performance of the f-PSA assay was investigated in buffer and in human plasma, respectively. In the human plasma, the limit of detection of f-PSA was estimated to be approximately 80 fM for 40 min of contact time, which adequately meets clinical requirements.
Yu
Fang
F
Max-Planck-Institute for Polymer Research, Ackermannweg 10, D-55128 Mainz, Germany.
Persson
Björn
B
Löfås
Stefan
S
Knoll
Wolfgang
W
D006801:Humans; D007118:Immunoassay / Q000379:methods*; D007700:Kinetics; D008297:Male; D017430:Prostate-Specific Antigen / Q000097:blood*; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence / Q000379:methods*; D020349:Surface Plasmon Resonance / Q000379:methods*
D017430:Prostate-Specific Antigen