Synthesis and Photophysical Properties of Conjugates of Green Fluorescent Protein (GFP) Chromophore and 2'-Deoxy-Uridine Developed as Labelled Building Blocks for Oligonucleotide Probes

Fluorescent probes with high signal/background ratio are needed for hybridization assays. Hence, the chromophore of green fluorescent protein (GFP), 4-hydroxybenzylidene-imidazolinone (HBI), was targeted as a potential fluorescent intercalator. For producing a building block for fluorescent oligonucleotide probes, 2'-deoxyuridine (dU) was conjugated with HBI via a flexible carbon-spacer. dUHBI conjugates highly fluoresce in glycerol (λem 460 nm, Φ 0.31), and are 109-fold more emissive than in methanol, implying the potential of dUHBI-labeled oligonucleotides as probes for hybridization assays.