Optical sensing with metalloporphyrins: towards nanostructured sensing devices

ROLANDO CARABALLO; ROCIO THEA; NICOLAS LOPEZ ABDALA; DIEGO ONNA; MARIANA HAMER; GALO A. A. SOLER ILLIA

Munich

Congreso; International Conference on Porphyrins and Phthalocyanines (ICPP); 2018

Friedrich-Alexander-Universitaet Erlangen-Nuernberg

Metalloporphyrins are excellent molecules for sensing specific targets due to their reactivity could be tune changing the metallic center and the porphyrin ligands. In general, the metalloporphyrin spectra shifts are small, in the order of 30 nm, making necessary a spectrophotometer for transducing the analyte concentration (1). We propose combing a metalloporphyrin thin film (MTF) and a photonic crystal (PC), a nanostructured optical filter synthesized from two oxide thin films with different refractive index, in order to develop a versatile and portatile sensing dipositive for small molecules, shown in Figure. The MTFs, made by layer-by-layer (LbL) deposition of water-soluble metalloporphyrins, were characterized by UV-VIS, fluorescence spectroscopy, cyclic voltammetry, SEM and AFM. These films are homogeneous and their thickness depends on the number of LbL cycles. The small molecules sensing spectra show width peaks and shift respect the original film of less than 50 nm. Using the MTF with their corresponding PC permit to quantify selected small analytes (such as NO, CO and H2O) (Figure).