Dennany Lynn, Hogan Conor F, Keyes Tia E, Forster Robert J
National Centre for Sensor Research, School of Chemical Sciences, Dublin City University, Dublin 9, Ireland.
Anal Chem. 2006 Mar 1;78(5):1412-7. doi: 10.1021/ac0513919.
The effect of surface confinement on the electrochemiluminescence (ECL) properties of metallopolymer [Ru(bpy)2(PVP)10]2+, where bpy is 2,2'-bipyridyl and PVP is poly(4-vinylpyridine), is reported. Immobilizing a luminescent material on an electrode surface can substantially modulate its photophysical properties. Significantly, our study revealed that the overall efficiency of the ECL reaction for the metallopolymer film is almost four times higher, at 0.15%, than the highest value obtained for [Ru(bpy)2(PVP)10]2+ dissolved in solution, (phi(ECL) = 0.04%). Electrochemistry has been used to create well-defined concentrations of the quencher Ru3+ within the film. Analysis of both the steady-state luminescence and lifetimes of the film reveals that static quenching by electron transfer between the photoexcited Ru2+ and the Ru3+ centers is the dominant quenching mechanism. The bimolecular rate of electron transfer is (2.5 +/- 0.4) x 10(6) M(-1) s(-1). The implications of these findings for ECL-based sensors, in terms of optimum luminophore loading, is considered.
本文报道了表面限制对金属聚合物[Ru(bpy)2(PVP)10]2+电化学发光（ECL）性质的影响，其中bpy为2,2'-联吡啶，PVP为聚（4-乙烯基吡啶）。将发光材料固定在电极表面可显著调节其光物理性质。值得注意的是，我们的研究表明，金属聚合物薄膜的ECL反应总效率几乎高出四倍，达到0.15%，高于溶解在溶液中的[Ru(bpy)2(PVP)10]2+的最高值（φ(ECL)=0.04%）。利用电化学方法在薄膜中产生了明确浓度的猝灭剂Ru3+。对薄膜的稳态发光和寿命分析表明，光激发的Ru2+与Ru3+中心之间通过电子转移进行的静态猝灭是主要的猝灭机制。电子转移的双分子速率为(2.5±0.4)×10(6) M(-1) s(-1)。本文还考虑了这些发现对基于ECL的传感器在最佳发光团负载方面的意义。
