The dye-modified deoxyuridine 5'-triphosphates (such as aminoallyl-dUTP) can be used to produce dye-containing DNA by conventional enzymatic incorporation methods such as reverse transcription, nick translation, random primed labeling, or PCR. This enzymatic fluorescence labeling method is widely used for both FISH probes and microarray-based experiments. DEAC-dUTP conjugate (#17011) is widely used as a blue fluorescence color with SpectrumAqua™ filter set (SpectrumAqua™ is the trademark of Vysis) since DEAC and SpectrumAqua have remarkably similar spectral properties. However, the extremely high hydrophobicity of DECA fluorophore make the DEAC conjugates easily adsorbed on plastic surfaces, resulting in high assay errors. iFluor® 440 dyes have excellent water solubility and are designed to be a superior replacement for DEAC dye. iFluor® 440-dUTP conjugate is a superior replacement for DEAC-dUTP conjugate. iFluor® 440 dye conjugates are significantly brighter than the corresponding bioconjugates of DEAC or other spectrally similar dyes (such as SpectrumAqua). iFluor® 440 fluorophore has its spectra well matched with the filter set of SpectrumAqua (SpectrumAqua™ is the trademark of Vysis).