Department of Chemistry, College of Sciences, Shanghai University, Shanghai 200444, PR China.
Spectrochim Acta A Mol Biomol Spectrosc. 2013 Nov;115:370-5. doi: 10.1016/j.saa.2013.06.039. Epub 2013 Jun 27.
Aspartic functionalized water-soluble perylene diimide, N,N'-di(2-succinic acid)-perylene-3,4,9,10-tetracarboxylic diimide (PASP) has two absorbance maximums at 527 and 498nm (ε≈1.7×10(4)Lcm(-1)mol(-1)) and two emission peaks at 547 and 587nm respectively. Emission intensities decrease with the increase of PASP concentrations in 20-100μM ranges. Spectral titrations demonstrate that each PASP can coordinate to two Cu(2+) ions in the absence of HEPES buffer. Its stability constant is estimated to be about 1.0×10(12)L(2)mol(-2) at pH 7.20 and its coordinate stoichiometry increased to 7.5 in the same pH in the presence of HEPES buffer. The emission of PASP will be completely quenched upon formation of Cu(2+) complex. The lowest "turn-off" fluorescence detection limit was calculated to be 0.3μM Cu(2+). PASP-Cu solution was used as a "turn-on" fluorescence biosensor to detect ATP. The sensitivity towards ATP is 0.3μM in 50mM HEPES buffer at pH 7.20, which is one of the most sensitive fluorescence sensors.
具有天冬氨酸功能的水溶性苝二酰亚胺，N，N'-二（琥珀酸）-苝-3,4,9,10-四羧酸二酰亚胺（PASP）在 527nm 和 498nm 处有两个吸收最大值（ε≈1.7×10(4)Lcm(-1)mol(-1)），在 547nm 和 587nm 处分别有两个发射峰。发射强度随 PASP 浓度在 20-100μM 范围内的增加而降低。光谱滴定表明，在没有 HEPES 缓冲液的情况下，每个 PASP 可以与两个 Cu(2+)离子配位。其稳定常数在 pH 7.20 时约为 1.0×10(12)L(2)mol(-2)，在相同 pH 值下存在 HEPES 缓冲液时，其配位化学计量比增加到 7.5。PASP 形成 Cu(2+)配合物时，其发射将完全猝灭。计算出的最低“关闭”荧光检测限为 0.3μM Cu(2+)。PASP-Cu 溶液被用作“开启”荧光生物传感器来检测 ATP。在 pH 7.20 的 50mM HEPES 缓冲液中，对 ATP 的灵敏度为 0.3μM，是最灵敏的荧光传感器之一。
