Time-Resolved Luminescence Microscopy and Microarray Using Europium Chelate Labels

The luminescent Eu complex, DTBTA-Eu, is highly stable in terms of ligand-metal dissociation, and can be labelled to amino groups of proteins and other bio-molecules. Owing to the long lifetime of Eu luminescence, time-resolved measurement of DTBTA-Eu removes background fluorescence and enhances the sensitivity of the labelled materials. This property was applied to time-resolved luminescence microscopy and DNA microarray. In these systems the high sensitivity and reliable quantification of the image was proved. In time-resolved images, autofluorescence of tissues and cells was dramatically reduced. In addition, due to the high stability of the metal complex towards photo-bleaching and ozone oxidation, which had been serious problems in the conventional normal fluorescence microscopy and microarray using organic dye labels, deterioration of the images on time elapse turned out to be drastically reduced in the timereesolved imaging, compared to the normal fluorescence images.