Fig. 3
From: Photosensitizing deep-seated cancer cells with photoprotein-conjugated upconversion nanoparticles
Measurement of FRET between UCNPs and KR-LP. a Schematic of ET pathway from CS-UCNPs (top) or Co-UCNPs (bottom) to KR-LP. b Spectral overlap between the emission of CS-UCNPs (donor) and the absorbance of KR-LP (acceptor). c−d Changes in the fluorescence (FL) intensity spectra of CS-UCNP-NH2 (c) and Co-UCNP-NH2 (d) in the absence and presence of KR-LP. e−f PL decay time curves of CS-UCNP-NH2 (e) and Co-UCNP-NH2 (f) in the absence and presence of KR-LP under 980 nm excitation and 550 nm emission. FRET, fluorescence resonance energy transfer