Fluorescence properties of fluorescein and rhodamine supported on alumina nanowire films

In this paper, alumina nanopore array films and nanowire films were prepared by anodic oxidation method, and fluorescein and rhodamine molecules were loaded onto their surfaces to fabricate composite fluorescent films. The effects of morphologies and annealing temperatures of alumina films on the fluorescence properties of the composite films were investigated. When loaded on alumina nanowire films, the properties of rhodamine B (RB), fluorescein (FL), rhodamine 110 (R110), rhodamine 6G (R6G) and the FRET (fluorescence resonance energy transfer) systems they constituted were studied in detail. Results show that the fluorescence emission of RB is stronger on alumina nanowire films than on alumina nanopore array films. The molecular structure of donor and acceptor can affect the energy transfer efficiency of FRET system (E), the fluorescence emission enhancement multiple of acceptor (IA(DA)/IA) and the transferred energy utilization factor (η). Compared to the systems of FL-R110, FL-R6G, R110-R6G, R110-RB and R6G-RB, FL-RB has the best comprehensive performance with the largest IA(DA)/IA (4.90) and η (6.42), despite its medium E (76.3%).