Two-Photon Probes for Golgi Apparatus: Detection of Golgi Apparatus in Live Tissue by Two-Photon Microscopy

Abstract

We have developed blue-and yellow-emitting two-photon probes (BGolgi-blue and PGolgi-yellow) from 6-(benzo[d]oxazol-2-y1)-2-naphthalylamine and 2,5-bis(benzo[d]-oxazol-2-yl)pyrazine derivatives as the fluorophores and trans-Golgi-network peptide (SDYQRL) as the Golgi-apparatus-targeting moiety. HeLa cells labeled with BGolgi-blue and PGolgi-yellow emitted two-photon-excited fluorescence at 462 and 560 nm, respectively, with effective two photon-action cross-section values of 1860 and 1600 x 10(-50) cm(4).s/photon, respectively. The probes can detect the Golgi apparatus in live cells and deep inside live tissue via two-photon microscopy at widely separated wavelength regions with high selectivity and minimal pH interference, and they are photostable and have low cytotoxicity.