Rhodamine‐formylaniline conjugate RFA has been developed as a Cu²⁺‐selective ratiometric fluorescent probe. The probe shows high selectivity towards Cu²⁺ ion through both its absorption and emission properties; and has been characterized by ¹H NMR, FTIR, ESI‐MS spectroscopy. Sensing of Cu²⁺ proceed through FRET process which is nicely depicted from steady‐state and fluorescence lifetime studies. From the measurement of fluorescence lifetime, the FRET mechanism has been established undoubtedly. The important parameters regarding FRET, namely the energy transfer efficiency (Φ_Et) and the Förster distance (R₀) have also been calculated by fluorescence measurement. The origin of different emission bands has been distinguished by recording excitation spectra. The lowest detection limit (DL) for Cu²⁺ ion was 4.2 ×10⁻⁷ M in Tris‐HCl buffered MeCN: H₂O (10 mM, 1:1 v/v).

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Cu（II）的比例荧光传感：FRET机理的阐明和生物成像应用

罗丹明-甲酰苯胺共轭RFA已开发为Cu 2 ^+-选择性比率荧光探针。该探针通过其吸收和发射特性对Cu ²⁺离子显示出很高的选择性。并通过¹ H NMR，FTIR，ESI-MS光谱进行了表征。Cu ^2+的传感通过FRET过程进行，这在稳态和荧光寿命研究中得到了很好的描述。从荧光寿命的测量，无疑已经建立了FRET机制。关于FRET的重要参数，即能量传递效率（_ΦEt）和Förster距离（R ₀）也已通过荧光测量计算得出。通过记录激发光谱来区分不同发射带的起源。 在Tris-HCl缓冲的MeCN：H ₂ O（10 mM，1：1 v / v）中，Cu ²⁺离子的最低检测限（DL）为4.2×10 ^-7M。