Figure 4

(a) FRET spectra of PAD at different concentrations of CEA (inset: enlarged portion of the curve peaks); (b) CIE chromaticity coordinates for test zones with different concentration of CEA; (c) Calibration. curve of FRET detection on PAD for the integrated luminescence intensity ratio FITC₅₂₀/Tm₄₈₀ versus the concentration of CEA.