Dipartimento di Ingegneria dell'Innovazione, Università degli Studi del Salento, I-73100 Lecce, Italy.
Chemphyschem. 2009 Dec 7;10(17):3077-82. doi: 10.1002/cphc.200900451.
In this contribution we report the design, preparation and characterization of bichromophoric Langmuir-Schäfer multilayer films which enable the simultaneous generation of nitric oxide (NO) and singlet oxygen (1)O(2) ((1)Delta(g)). They are achieved by exploiting effective interfacial electrostatic interactions between the floating film of a cationic amphiphilic nitric oxide (NO) photodonor and an anionic porphyrin dissolved in the water subphase. The morphology and the spectroscopic features of the floating films at the water-air interface are inspected by Brewster angle microscopy and UV/Vis reflection spectroscopy, respectively. Multilayer films containing both the chromogenic centres are obtained by horizontal lifting deposition onto hydrophobized quartz substrates and are characterized by steady-state UV/Vis absorption, fluorescence and laser flash photolysis. The anionic porphyrin units are entangled into the films network mainly in their monomeric forms and no significant intra and inter-chromophoric interaction occur in the excited state, preserving the photochemical independency of the two photoactive units in the multilayers. The capability of the bichromophoric films to delivery NO and singlet oxygen, (1)O(2) ((1)Delta(g)), under light excitation is unambiguously demonstrated by the direct and in real time monitoring of these transient species using an ultrasensitive electrode and a time-resolved infrared luminescence apparatus, respectively.
在本研究中，我们报告了双生色 Langmuir-Schäfer 多层膜的设计、制备和表征，该多层膜可同时生成一氧化氮 (NO) 和单线态氧 (1)O(2) ((1)Delta(g))。通过利用阳离子两亲性一氧化氮 (NO) 光供体的浮动膜与溶解在水亚相中的阴离子卟啉之间的有效界面静电相互作用来实现这一点。通过布鲁斯特角显微镜分别检查了在水-气界面处的浮动膜的形态和光谱特征。通过水平提拉沉积到疏水性石英基底上，获得了包含发色中心的多层膜，并通过稳态 UV/Vis 吸收、荧光和激光闪光光解来对其进行表征。阴离子卟啉单元主要以单体形式纠缠在薄膜网络中，在激发态中不会发生显著的内和间发色团相互作用，从而保持了多层膜中两个光活性单元的光化学独立性。通过使用超灵敏电极和时间分辨红外发光仪器直接和实时监测这些瞬态物质，明确证明了双生色薄膜在光激发下输送一氧化氮和单线态氧 ((1)O(2) ((1)Delta(g))) 的能力。
