title: New luminescent europium(III) chelates for DNA labeling.
abstract: The new europium(III) chelate [2,2',2'',2'''-[[4'-(aminobiphenyl-4-yl)-2,2':6',2''-terpyridine- 6,6''-diyl]bis(methylenenitrilo)]tetrakis(acetato)] europium(III) (ATBTA-Eu3+) and its 4,6-dichloro-1,3,5-triazinyl and succinimidyl derivatives (DTBTA and NHS-ATBTA, respectively) were synthesized and characterized. Both labeling complexes DTBTA-Eu3+ and NHS-ATBTA-Eu3+ are luminescent. Especially DTBTA-Eu3+ is strongly luminescent, with a luminescence quantum yield of 9.1%, molar extinction coefficient of 3.1 x 10(4) cm(-1) M(-1) (335 nm), and luminescence lifetime of 1.02 ms. The excitation and emission maximum wavelengths of DTBTA-Eu3+ are 335 and 616 nm, respectively. The complex is very stable in aqueous buffers, with a conditional formation constant log K(DTBTA-Eu) of 25.0 at pH 8, and can be conjugated to DNA and proteins. The chelates are also highly resistant to thermal decomposition, photodegradation, and ozone oxidation. These properties prove that DTBTA-Eu3+ is suitable as a luminescence label in DNA assays.
authors: Department of Chemistry, Advanced Research Institute for Science and Engineering, Waseda University, Shinjuku-ku 169-8555, Tokyo, Japan.
authors: Takuya
authors: T
authors: Nishioka
authors: Jingli
authors: J
authors: Yuan
authors: Yuji
authors: Y
authors: Yamamoto
authors: Keiko
authors: K
authors: Sumitomo
authors: Zhen
authors: Z
authors: Wang
authors: Kimikazu
authors: K
authors: Hashino
authors: Chihiro
authors: C
authors: Hosoya
authors: Keisuke
authors: K
authors: Ikawa
authors: Guilan
authors: G
authors: Wang
authors: Kazuko
authors: K
authors: Matsumoto