Self-organization of a sulfonamido-porphyrin in Langmuir monolayers and Langmuir–Blodgett films

Abstract

Langmuir monolayers (LM) and Langmuir-Blodgett (LB) films of pure lipophilic meso-tetra(4-dodecylaminosulfophenyl)porphyrin (PC12) and mixed with the anionic surfactant sodium hexadecylsulfate (SHS) were studied. The molecular packing and structure of PC12 and PC12-4SHS with variable surface pressure were investigated by surface pressure-area measurements, steady-state absorption, fluorescence emission and anisotropy, as well as by fluorescence lifetime imaging microscopy (FLIM). At low surface pressure, the porphyrin molecules are organized with the rings tilted on the water surface whereas at high surface pressure the porphyrin rings achieve a more perpendicular arrangement. Using the FLIM images a gradual change of aggregates into large "islands" is observed. Different patterns are observed in the pure PC12 multilayer films (n = 3 and 5) with ordered patches superimposed which are not observed in the PC12-4SHS multilayer LB films.

Imaging proteins in vivo using fluorescence lifetime microscopy

“…Applications in forensic science, 10 combustion research, 11 microfluidic systems, [12][13][14][15] artworks 16 and lipid order problems in physical chemistry 17,18 have also been reported.…”

Fluorescence Spectroscopy of Porphyrins and Phthalocyanines: Some Insights into Supramolecular Self-Assembly, Microencapsulation, and Imaging Microscopy

“…FLIM has been a privileged technique in our group to further investigate the interaction of porphyrinoids in supramolecular and nanostructured systems that include micelles [ 89 , 115 ], liposomes [ 92 ], molecular self-aggregates [ 34 , 43 ], Langmuir-Blodgett films [ 168 ], dendrimers [ 21 ], polyelectrolyte microcapsules [ 89 , 90 , 169 ], carbon nanotubes [ 39 ], graphene oxide [ 40 ], and gold nanostructures [ 150 , 152 , 154 , 155 , 156 ], as highlighted in some examples previously described in this review.…”

Fluorescence lifetime imaging (FLIM): Basic concepts and some recent developments

“…However, applications in diverse areas such as forensic science (Bird et al, 2007), combustion research (Ehn et al, 2011;Ni and Melton, 1996), luminescence lifetime mapping in diamond (Liaugaudas et al, 2009(Liaugaudas et al, , 2012, microfluidic systems (Benninger et al, 2005a(Benninger et al, , 2006Elder et al, 2006;Graham et al, 2010;Magennis et al, 2005;Robinson et al, 2008), art conservation (Comelli et al, 2004(Comelli et al, , 2005, remote sensing (Esposito, 2012;Ge et al, 2012;Lin et al, 2012), lipid order problems in physical chemistry (Togashi et al, 2005), the spatial distribution of dopants in perovskite oxides (Rodenbücher et al, 2013) and temperature sensing (Bennet et al, 2011;Benninger et al, 2006;Graham et al, 2010;Mendels et al, 2008;Okabe et al, 2012) have also been reported. FLIM has been carried out from the UV (Li et al, 2004;Schüttpelz et al, 2006) to the near infrared (Becker and Shcheslavskiy, 2013) and it is not surprising that fluorescence lifetime-based imaging is widely used in the biomedical sciences, and that this trend shows no signs of abating.…”