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Copper-doped semiconductors are designed to photoassist the alkyne-azide cycloaddition catalysis by Cu(I). Upon irradiation, injection of electrons from the semiconductor into copper oxide nanostructures produces the catalytic Cu(I) species. The new catalysts are air- and moisture-tolerant and can be readily recovered after use and reused several times.

A covalently linked BODIPY−fullerene C60 dyad (BDP−C60) was synthesized as a two‐segment structure, which consists of a visible light‐harvesting antenna attached to an energy or electron acceptor moiety. This structure was designed to improve the photodynamic action of fullerene C60 to inactivate bacteria. The absorption spectrum of BDP−C60 was found to be a superposition of the spectra of its constitutional moieties, whereas the fluorescence emission of the BODIPY unit was strongly quenched by the fullerene C60. Spectroscopic, calculations, and redox studies indicate a competence between photoinduced energy and electron transfer. Protonating the dimethylaminophenyl substituent through addition of an acidic medium led to a substantial increase in the fluorescence emission, triplet excited state formation, and singlet molecular oxygen production. At physiological pH, photosensitized inactivation of Staphylococcus aureus mediated by 1 μM BDP−C60 exhibited a 4.5 log decrease of cell survival (>99.997 %) after 15 min irradiation. A similar result was obtained with Escherichia coli using 30 min irradiation. Moreover, proton‐activated photodynamic action of BDP−C60 turned this dyad into a highly effective photosensitizer to eradicate E. coli. Therefore, BDP−C60 is an interesting photosensitizing structure in which the light‐harvesting antenna effect of the BODIPY unit combined with the protonation of dimethylaminophenyl group can be used to improve the photoinactivation of bacteria.

A novel biscarbazol-triphenylamine end-capped dendrimeric zinc(II) porphyrin (DP 5) was synthesized by click chemistry. This compound is a cruciform dendrimer, which bears a nucleus of zinc(II) tetrapyrrolic macrocycle substituted at the meso positions by four identical substituents. These are formed by a tetrafluorophenyl group that possess in the para position a triazole unit. This nitrogenous heterocyclic is connected to a 4,4'-di(N-carbazolyl)triphenylamine group by means of a phenylenevinylene bridge, which allows the conjugation between the nucleus and this external electropolimerizable carbazoyl group. In this structure, dendrimeric arms act as light-harvesting antennas, increasing the absorption of blue light and as electroactive moieties. The electrochemical oxidation of the carbazole groups contained in the terminal arms of the DP 5 was used to obtain novel stable and reproducible fully π-conjugate photoactive polymeric films (FDP 5). First, the spectroscopic characteristics and photodynamic properties of DP 5 were compared with its constitutional components derived of porphyrin P 6 and carbazole D 7 moieties in solution. The fluorescence emission of the dendrimeric units in DP 5 were strongly quenched by the tetrapyrrolic macrocycle, indicating photoinduced energy transfer. In addition, FDP 5 film showed the Soret and Q absorption bands and red fluorescence emission of the corresponding zinc(II) porphyrin. Also, FDP 5 film was highly stable to photobleaching and it was able to produce singlet molecular oxygen in both N,N-dimethylformamide and water. Therefore, the porphyrin units embedded in the polymeric matrix of FDP 5 film mainly retain the photochemical properties. Photodynamic inactivation mediated by FDP 5 film was investigated in Staphylococcus aureus and Escherichia coli. When a cell suspension was deposited on the surface, complete eradication of S. aureus and a 99% reduction in E. coli survival were found after 15 min and 30 min irradiation, respectively. Also, FDP 5 film was highly effective to eliminate individual bacteria attached to the surface. In addition, PDI sensitized by FDP 5 film produced more than 99.99% bacterial killing in biofilms formed on the surface after 60 min irradiation. The results indicate that FDP 5 film Page 2 of 49 ACS Paragon Plus Environment ACS Applied Materials & Interfaces represents an interesting and versatile photodynamic active material to eradicate bacteria as planktonic cells, individual attached microbes or biofilms.

Experimental and theoretical study on the effect of shallow and deep defects on photovoltaic performance, luminescence, surface photovoltage, and density of states.

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A porphyrin-fullerene C60 dyad (TCP-C60) substituted by carbazoyl groups was used to obtain electrogenerated polymeric films on optically transparent indium tin oxide (ITO) electrodes. This approach produced stable and reproducible polymers, holding fullerene units. The properties of this film were compared with those formed by layers of TCP/TCP-C60 and TCP/ZnTCP. Absorption spectra of the films presented the Soret and Q bands of the corresponding porphyrins. The TCP-C60 film produced a high photodecomposition of 2,2-(anthracene-9,10-diyl)bis(methylmalonate), which was used to detect singlet molecular oxygen O2((1)Δg) production in water. In addition, the TCP-C60 film induced the reduction of nitro blue tetrazolium to diformazan in the presence of NADH, indicating the formation of superoxide anion radical. Moreover, photooxidation of L-tryptophan mediated by TCP-C60 films was found in water. In biological media, photoinactivation of Staphylococcus aureus was evaluated depositing a drop with 2.5 × 10(3) cells on the films. After 30 min irradiation, no colony formation was detected using TCP-C60 or TCP/TCP-C60 films. Furthermore, photocytotoxic activity was observed in cell suspensions of S. aureus and Escherichia coli. The irradiated TCP-C60 film produced a 4 log decrease of S. aureus survival after 30 min. Also, a 4 log reduction of E. coli viability was obtained using the TCP-C60 film after 60 min irradiation. Therefore, the TCP-C60 film is an interesting and versatile photodynamic active surface to eradicate bacteria.

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