Effect of interaction with micelles on the excited-state optical properties of zinc porphyrins and J-aggregates formation

Studying the intersystem crossing rate and triplet quantum yield of meso-substituted porphyrins by means of pulse train fluorescence technique

“…For example, Gonçalves et al [20] demonstrated that the insertion of zinc in sulfonated porphyrin free-bases drastically reduced the ISC rate from 13 ns [21] to 2.2 ns [20]. Sampaio et al [22] have shown that free-base 5,10,15,20-tetra(4-pyridyl)porphyrin (H 2 TP y P) with ruthenium(II) ions bound at the peripheral groups of the macrocycle increases the ISC time about twofolds compared to porphyrins without Ru(II) (from 14 ns to 25 ns).…”

Photophysical Properties and Aggregation Behavior of Transition Metal Tetraphenylporphyrin Tetrasulfonate Complexes in Microheterogeneous Media

“…[28] The above findings are in a good agreement with the results obtained under similar experimental conditions earlier. [7,9,10,26] A special type of ionic associate formation was observed for CoTPPS in presence of PDDA. Unlike the bulk water CoTPPS solution, a freshly prepared PDDAcontaining system exhibited significant fluorescence at 609 nm, resulting from the possible heteroaggregate formation (Figure 6,a).…”

“…During the past decade much work has been done on TPPS interactions with surfactants, [7][8][9][10][11] polyelectrolytes [12][13][14][15] and especially biomacromolecules. [16][17][18] The increasing research interest in porphyrin behavior within microorganized systems is due to their possible application as photosensitizers in photodynamic therapy (PDT), [19] since the microheterogeneous medium is known to favor supramolecular ionic associate and 341 Макрогетероциклы / Macroheterocycles 2013 6(4) 340-344 M. A. Gradova, A. V. Lobanov heteroaggregate formation, especially at low pH abundant in cancer cells.…”

Influence of halogen atoms and protonation on the photophysical properties of sulfonated porphyrins

“…Combination of Z-scan measurements, UV-vis absorption and fluorescence spectroscopies have allowed to find contributions from radiative, internal conversion and intersystem crossing processes, which allow evaluating its potential for optical applications [30,31]. In this way, the present work reports on the study of photophysical characteristics of sulfonated porphyrins and how they are influenced by presence of one or two halogens (fluorine of chlorine) in the ortho positions of phenyl rings and the macrocycle protonation.…”

“…The Z-scan technique was shown to be an appropriated and powerful tool to investigate nonlinear properties and photophysical characteristics of organic molecules aiming at applications in photonic and photomedicine [27][28][29][30][31]. Combination of Z-scan measurements, UV-vis absorption and fluorescence spectroscopies have allowed to find contributions from radiative, internal conversion and intersystem crossing processes, which allow evaluating its potential for optical applications [30,31].…”