Two-photon absorption and cell imaging of two multi-branched dyes based on curcumin

Two novel multibranched dyes curcumin-based: 1,7-bis(4'-propyloxy-3'-methyloxy-phenyl)-3-propyloxy-5-carbonyl-1,6-heptadiene (dye 1) and 1,7-bis(4'-acetate ethyloxy-3'-methyloxy-phenyl)-1,6-heptadiene-4,4-diacetate ethyl-3,5-dione (dye 2) were easily prepared. Their one- and two-photon absorption properties have been investigated carefully. The two-photon absorption (TPA) cross sections measured by two-photon excited fluorescence (TPEF) were determined to be 1143 and 842 GM for dye 1 and dye 2, respectively. Cell viability tests revealed the as-prepared compounds possessed low cytotoxicity against MCF-7 cell lines over a period of at least 24 h. In addition, in vitro and in vivo studies demonstrated the dye 1 could enter into tumor cells, and even rapid accumulate in tumor tissues, which makes it an ideal organic material for biomedical imaging. (C) 2015 Elsevier Ltd. All rights reserved.