Fig 1: Various shapes of 3D paddle structures. The paddle screw shown in the blue box was selected considering that it was convenient to manufacture it with 3D printing and that it matched well with 1.5 mL microtubes for PSA immunoassay.
Fig 2: Schematic illustration of a sandwich immunoassay reaction for PSA occurring on the surface of a paddle screw-type device utilized in this study.
Fig 3: Changes in fluorescence signal ratio in the paddle screw-based immunoassay according to PSA concentration. The lower plot (solid square marks) shows the results of a well plate sandwich immunoassay. The upper plot (solid circle marks) shows the results of a paddle screw-based sandwich immunoassay. Data in red circles deviated from the logarithmic linear range.
Fig 4: (a) Fluorescence spectra of FITC released by DTT treatment after sandwich immunoassay according to PSA concentration, and (b) fluorescence intensity versus PSA concentration.
Fig 5: A custom-made paddle screw rotating system. Microtubes (1.5 mL) for PSA assay located at the bottom of the system consisted of one solution containing complex of PSA and anti-PSA detecting antibody–FITC conjugates, three PBS buffer solutions, and one DTT solution.
Supplier Page from Abcam for Recombinant Human Prostate Specific Antigen protein