An oligo(p-phenylene vinylene) derivative (OPV-pfp) functionalized with pentafluorophenol active ester is designed and synthesized. The high reactivity of OPV-pfp with biological small molecules or macro molecules containing amino groups under physiological conditions leads to spectral changes of OPV-pfp; thus, spatial reactivity discrimination for different subcellular structures inside cells is realized by triggering and imaging the fluorescence signal change of the OPV-pfp.