fig1

Figure 1. Analysis of disulfide reduction and PSMA binding specificity of the DUPA-FRET conjugate in Scheme 1. (A) Depiction of changes of emitted fluorescence upon DUPA-FRET conjugate reduction. See Scheme 1 for color coding; (B, C) reduction of the DUPA-FRET conjugate was analyzed using RP-C18 HPLC (Abs = 280 nm) in the absence (B) and presence (C) of a 10-fold excess of dithiothreitol; (D) DUPA-FRET conjugate (100 nmol/L) was incubated with PC-3 (human PSMA-negative) and LNCaP (human PSMA-positive) cells for 1 h at 37 °C. Cells were then excited by a green (488 nm) laser and emitted green and red fluorescence were visualized via confocal microscopy