Dimethyl-pepep (D-pepep), a newly developed and very efficient two-photon absorber, has been tested here for two-photon excitation (TPE) cellular imaging. The spectral characteristics of the dye following one-photon excitation (OPE) and TPE (excitation and emission spectra, fluorescence lifetime, molecular brightness, saturation intensity) are reported. In vitro interaction studies with biomolecules show that dimethyl-pepep has a large affinity for DNA. A comparison with a widely used DNA stainer, 4-6-diamidino-2-phenylindole (DAPI) bound to DNA shows that the D-pepep brightness is one order of magnitude higher than that of DAPI, making this dye suitable for microscopy and imaging applications. TPE images taken from double-stained yeast Saccharomyces cerevisiae cells have revealed that D-pepep localizes mainly in the nucleus, similarly to DAPI, and in mitochondria, although to a minor extent. Preliminary tests have shown that the dye cellular toxicity is negligible. © 2004 Elsevier B.V. All rights reserved.
Abbotto, A., Baldini, G., Beverina, L., Chirico, G., Collini, M., D'Alfonso, L., et al. (2005). Dimethyl-pepep: A DNA probe in two-photon excitation cellular imaging. BIOPHYSICAL CHEMISTRY, 114(1), 35-41 [10.1016/j.bpc.2004.11.004].
Dimethyl-pepep: A DNA probe in two-photon excitation cellular imaging
ABBOTTO, ALESSANDRO;BALDINI, GIANCARLO;BEVERINA, LUCA;CHIRICO, GIUSEPPE;COLLINI, MADDALENA;D'ALFONSO, LAURA;NARDO, LUCA;PAGANI, GIORGIO ALBERTO
2005
Abstract
Dimethyl-pepep (D-pepep), a newly developed and very efficient two-photon absorber, has been tested here for two-photon excitation (TPE) cellular imaging. The spectral characteristics of the dye following one-photon excitation (OPE) and TPE (excitation and emission spectra, fluorescence lifetime, molecular brightness, saturation intensity) are reported. In vitro interaction studies with biomolecules show that dimethyl-pepep has a large affinity for DNA. A comparison with a widely used DNA stainer, 4-6-diamidino-2-phenylindole (DAPI) bound to DNA shows that the D-pepep brightness is one order of magnitude higher than that of DAPI, making this dye suitable for microscopy and imaging applications. TPE images taken from double-stained yeast Saccharomyces cerevisiae cells have revealed that D-pepep localizes mainly in the nucleus, similarly to DAPI, and in mitochondria, although to a minor extent. Preliminary tests have shown that the dye cellular toxicity is negligible. © 2004 Elsevier B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.