Single- and Multiphoton Turn-On Fluorescent Fe3+ Sensors Based on Bis(rhodamine)

详细信息    查看全文

• 作者：Aruna J. Weerasinghe ; Carla Schmiesing ; Shankar Varaganti ; Guda Ramakrishna ; Ekkehard Sinn
• 刊名：Journal of Physical Chemistry B
• 出版年：2010
• 出版时间：July 29, 2010
• 年：2010
• 卷：114
• 期：29
• 页码：9413-9419
• 全文大小：387K
• 年卷期：v.114,no.29(July 29, 2010)
• ISSN：1520-5207

文摘

Selective and sensitive turn-on fluorescent Fe³⁺ sensors based on novel bis(rhodamine) dye molecules are reported. The compounds are synthesized with very high yields and characterized with NMR, ESI mass spectrometry, and elemental analysis. Single- and two-photon fluorescence enhancement is observed for both molecules in the presence of Fe³⁺. High selectivity and sensitivity is observed over other metal ions and is shown to be due mainly to the spirolactam ring-opening power of Fe³⁺. All measurements are made in buffer environments simulating biological conditions to facilitate single- and multiphoton fluorescence imaging of Fe³⁺ in vivo and in vitro. Larger enhancement of fluorescence for both one- and two-photon excitation makes them suitable candidates for fluorescent labeling of biological systems. Two photon cross-section and time-resolved fluorescence measurements are utilized to understand the selectivity of the present sensors for Fe³⁺-sensing.