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In the continuation of our sustained interest in porphyrin-based dendrimers and their use as luminescent photosensitizers for two-photon photodynamic therapy (2P-PDT), we wondered about the effect of changing the connectors in our macromolecular structures. We also wanted to initiate preliminary studies on meso-tetraarylporphyrins decorated with more electron-releasing arms. Thus, various meso-tetrafluorenylporphyrin-cored star-shaped and dendrimeric derivatives have been synthesized and characterized, as well as their zinc(II) complexes. In the new dendrimeric derivatives, the peripheral fluorenyl units of the dendrons are linked to the inner core either by N-phenylcarbazole (CCbz) or triphenylamine (CTpa) connectors instead of the more classic 1,3,5-phenylene (CPh) linkers previously used by us. Selected linear and non-linear optical (LO and NLO) properties were then determined for these compounds via absorption or emission studies and by two-photon excited fluorescence (TPEF) measurements. It was found that the CCbz-containing dendrimer, which has the most rigid structure, exhibits a significantly lower two-photon absorption (2PA) cross-section than its CTpa analog, presenting a more flexible structure while rather similar luminescence and singlet oxygen activation quantum yields are found for both. The origin of this unexpected discrepancy is briefly discussed based on our photophysical data. It is then demonstrated that the latter dendrimer also outperforms several closely related dendrimers in terms of 2PA action cross-section and 2PA-oxygen sensitization, making its molecular architecture quite appealing for developing new 2PA photosensitizers suited to theranostic uses.

The luminol chemiluminescent reaction is among well-known quantitative methods in analytical spectroscopy due to its high sensitivity to presence of catalyst and low background signal. In this study, magnetic nanocomposite of Fe3O4/SiO2/TiO2/CoIIITHPP (THPP : tetrahyroxyphenylporphyrin) has been synthesized by co-precipitation method and characterized with fourior transform-infrared (FT-IR), X-ray photoelectron spectroscopy (XRD), vibrating sample magnetometer (VSM), scanning electron microscope (SEM), trasmiddion electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS. For the fist time, this magnetic nanocomposite has been used as catalyst of chemolumincence reactions and showed high catalytic effect on the luminol-H2O2 system. The recovery of catalyst was easily performed by applying the external magnetic field.

Abstract In this work, we present Zn, CoII, and MnIII metalated meso‐tetra‐[4‐(methylthio) phenyl] porphyrin ([Zn(TMtPP)], [CoII(TMtPP], and [MnIII(TMtPP)Cl]) as electrocatalysts and photoelectrocatalysts for electrochemical detection and photoelectrocatalytic degradation of pentachlorophenol (PCP). The complexes were characterized using UV‐visible spectroscopy, mass spectroscopy, and elemental analysis. Proton nuclear magnetic resonance (1H NMR) studies were only conducted for the Zn derivative. The electrochemical detection of PCP was carried out using cyclic voltammetry and chronoamperometry. [CoII(TMtPP)] showed better detection limit. For photoelectrocatalytic (PEC) degradation studies of PCP, linear sweep voltammetry and UV‐visible spectra were employed. [Zn(TMtPP)] showed better removal efficiency. The main species responsible for the PEC degradation were found to be superoxide radicals (⋅O2) and electron holes (h+).

Abstract Molecular layer deposition (MLD) is an incredibly powerful and flexible tool for designing completely new materials with novel and unique properties. The low temperature layer‐by‐layer approach and the use of highly reactive reactants allows one to combine vastly different organic and inorganic species and construct nanostructures with subnanometer precision. If not limited by the volatility of the reactants involved, the possibilities will be endless. This is most notable for the organic building blocks where an overall low volatility severely limits the toolbox of large molecules with interesting optical and electrical properties such as red‐ox activity and optical conversion. In this work, different strategies for molecular design of large molecules are investigated that allow vaporization while still having the necessary reactivity for MLD growth. Using these strategies, film growth with perylene and porphyrin derivatives, both molecules well known for their functional and optical properties are successfully achieved. With this knowledge, there is an opening to include much larger and more complex organic molecules into the world of vapor phase chemistry.

The synthesis of photoluminescent pyrene derivatives and their biomaterial applications in sugar, porphyrin, perylene, and dendrimer systems hold great promise in advancing biomaterial science and technology. They are explored in depth, emphasizing their potential in various biomedical fields. The review discusses their use in biosensing, imaging, drug delivery, and other biomaterial applications. It highlights the advantages offered by each derivative system, such as biocompatibility, stability, and functionalization capabilities, which are essential for their successful integration into biomaterial systems. This review provides a comprehensive analysis of the current state of research in this field, highlighting the potential for these derivatives to contribute to innovative biomaterial applications and pave the way for future advancements.

The aim of this study was to investigate whether antimicrobial blue light (aBL) can cause the death of Aggregatibacter actinomycetemcomitans (A.a) and to determine the influence of different culture media, specifically brain heart infusion and blood agar, on bacterial survival fraction. An LED emitting at 403 ± 15 nm, with a radiant power of 1W, irradiance of 588.2 mW/cm2, and an irradiation time of 0 min, 1 min, 5 min, 10 min, 30 min, and 60 min, was used. The plates were incubated in microaerophilic conditions at 37 °C for 48 h, and the colony-forming units were counted. The photosensitizers were investigated using spectroscopy and fluorescence microscopy. There was no significant difference between the culture media (p > 0.05). However, a statistical reduction in both media was observed at 30 min (1058 J/cm2) (p < 0.05). The findings of this study suggest that aBL has the potential to kill bacteria regardless of the culture media used. Light therapy could be a promising and cost-effective strategy for preventing periodontal disease when used in combination with mechanical plaque control. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) as a coating material for gold nanorods (AuNRs) has gained interest in reducing toxicity and improving the photothermal profiling of AuNRs. However, there is still a challenge regarding the storage of colloidal suspensions of GO-coated AuNRs (GO@AuNRs). Hence, the conjugation of GO@AuNRs to meso-tetra-(4-sulfonatophenyl)porphyrin (TPPS4), an anionic water-soluble porphyrin, has been reported to enhance their re-dispensability and improve their phototherapeutic properties. The AuNRs and GO were synthesised using seed-mediated and Hummers' methods, respectively. The GO@AuNRs were conjugated to TPPS4 and characterised using ultraviolet–visible–near-infrared (UV-Vis-NIR) spectroscopy, zeta analyser, dynamic light scattering (DLS), photoluminescence spectroscopy (PL), x-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM) and Fourier-transform infrared spectroscopy (FTIR) before freeze-drying. The results showed that the AuNRs were sandwiched between GO and TPPS4. After freeze-drying, the freeze-dried conjugate was dispensed in deionised water without adding cryoprotectants and its properties were compared to those of the unfreeze-dried conjugate. The results showed that the freeze-dried conjugate contained similar optical properties to the unfreeze-dried conjugate. However, the bare GO@AuNRs showed a change in the optical properties after freeze-drying. These results revealed that porphyrin is an excellent additive to reduce the freeze-drying stress tolerance of GO@AuNRs. The freeze-dried conjugate also showed both singlet oxygen and photothermal properties of GO@AuNRs and porphyrin. These results indicated that the freeze-dried conjugate is a promising dual photodynamic and photothermal agent, and porphyrin can act as a cryoprotectant. [ABSTRACT FROM AUTHOR]

Porphyrin‐based porous organic polymers (Por‐POPs) are attracting increasing attention because of their potential in visible light photocatalysis. The distinctive attributes of Por‐POPs have been elucidated by investigating their response to specific reactions, such as the aerobic oxidation of sulfides. However, most researchers choose porphyrin molecules with relatively short peripheral substituent chains and strong stiffness to construct porphyrin‐based materials, especially Por‐POPS. Herein, we designed and prepared a flexible POP material H2Pp‐TAPM by incorporating extra π‐conjugated rigid units TAPM into a relatively flexible porphyrin monomer H2Pp through imine linkages. The POP synthesized in this study has demonstrated the ability to facilitate the transfer and dissociation of photogenerated electron–hole pairs, leading to the production of singlet oxygen 1O2 and superoxide radical anions O2˙−. These anions act as effective mediators for the selective aerobic oxidation of sulfides, resulting in the conversion of 99% and the selectivity more than 99%. Furthermore, the H2Pp‐TAPM has excellent stability and recyclability, indicating its attractiveness as heterogeneous photocatalyst for the transformation of organic compounds. This makes it a promising candidate for visible‐light‐driven reactions. [ABSTRACT FROM AUTHOR]

Bacterial resistance to antibiotics is a critical global health issue and the development of alternatives to conventional antibiotics is of the upmost relevance. Antimicrobial photodynamic therapy (aPDT) is considered a promising and innovative approach for the photoinactivation of microorganisms, particularly in cases where traditional antibiotics may be less effective due to resistance or other limitations. In this study, two β-modified monocharged porphyrin-imidazolium derivatives were efficiently incorporated into polyvinylpyrrolidone (PVP) formulations and supported into graphitic carbon nitride materials. Both porphyrin-imidazolium derivatives displayed remarkable photostability and the ability to generate cytotoxic singlet oxygen. These properties, which have an important impact on achieving an efficient photodynamic effect, were not compromised after incorporation/immobilization. The prepared PVP-porphyrin formulations and the graphitic carbon nitride-based materials displayed excellent performance as photosensitizers to photoinactivate methicillin-resistant Staphylococcus aureus (MRSA) (99.9999% of bacteria) throughout the antimicrobial photodynamic therapy. In each matrix, the most rapid action against S. aureus was observed when using PS 2. The PVP-2 formulation needed 10 min of exposure to white light at 5.0 µm, while the graphitic carbon nitride hybrid GCNM-2 required 20 min at 25.0 µm to achieve a similar level of response. These findings suggest the potential of graphitic carbon nitride-porphyrinic hybrids to be used in the environmental or clinical fields, avoiding the use of organic solvents, and might allow for their recovery after treatment, improving their applicability for bacteria photoinactivation. [ABSTRACT FROM AUTHOR]

Results are presented from investigating the dependence of the ratio of the intensity of these bands on temperature in the range of 25–75°C for nonmetalated and zinc metalated porphyrins, along with porphyrin dyads in solutions of 1,2-dichloroethane. A comparative analysis of the thermometric parameters of these molecules is performed. [ABSTRACT FROM AUTHOR]

Gold nanoparticles are widely used as local heaters under optical excitation. Hybrid molecular-plasmon nanostructures based on gold nanoparticles and water-soluble porphyrin have been developed. A colloidal solution of gold nanoparticles was obtained by laser ablation of metallic gold in water, ensuring its highest chemical purity. The hybrid nanostructures formation was performed due to the Coulomb interaction of cationic porphyrin and gold nanoparticles. The revealed functional properties of hybrid nanostructures make them promising for controllable nano-heater applications (for example, photothermal therapy). Gold nanoparticles act as heaters, whereas porphyrin serves as a fluorescent thermometer with a single optical excitation. [ABSTRACT FROM AUTHOR]

Ferrocenyl‐substituted nickel(II) norcorrole and nickel(II) porphyrin (Fc2NiNc and Fc2NiPor, respectively) are prepared as active electrode materials for dual‐ion batteries, which enables the systematically study of aromaticity and antiaromaticity for organic electrode materials. Intrinsically, Fc2NiNc and Fc2NiPor electrodes have excellent electrochemical behaviors with dual ion interaction with Li cations and bis(fluorosulfonyl)amide [FSA]– inorganic anions from the ionic liquid electrolyte, inducing high capacities (259 mAh g−1 for Fc2NiNc and 200 mAh g−1 for Fc2NiPor). The dominance of pseudocapacitive charge storage is exhibited by the Fc2NiNc and Fc2NiPor electrodes giving rise to rapid charge‐discharge processes. Computational calculation conclusively demonstrates the mechanism of multi‐electron redox reaction resulting in high discharge capacities and aromatic stabilization energy toward achieving a stable long‐term cyclability over 1000 cycles at high current density. Furthermore, Li4Ti5O12/IL/Fc2NiNc cells exhibit high power and energy densities (234 Wh kg−1 at 118 W kg−1) and accomplish outstanding cyclability over 10 000 cycles. This work provides a strategy for designing robust organic electrode materials for dual‐ion batteries. [ABSTRACT FROM AUTHOR]

Heterogeneous photocatalysts have attracted extensive attention in photo‐induced electron transfer‐reversible addition–fragmentation chain transfer (PET‐RAFT) polymerization due to their remarkable advantages such as easy preparation, tunable photoelectric properties, and recyclability. In this study, zinc (II) 5,10,15,20‐tetrakis(4‐aminophenyl)porphyrin (ZnTAPP)‐based poly‐porphyrin nanoparticles (PTAPP‐Zn) are constructed by an emulsion‐directed approach. It is investigated as a heterogeneous photocatalyst for PET‐RAFT polymerization of various methacrylate monomers under visible light exposure, and the reactions show refined polymerization control with high monomer conversions. Furthermore, it is demonstrated that the PTAPP‐Zn nanoparticles with the larger pore size enhance photocatalytic activity in PET‐RAFT polymerization. In addition, the capabilities of oxygen tolerance and temporal control are demonstrated and PTAPP‐Zn particles can be easily recycled and reused without an obvious decrease in catalytic efficiency. [ABSTRACT FROM AUTHOR]

Recently, carbon-based nanomaterials have attracted significant attention as promising metal-free nanocatalysts for activating persulfates in wastewater treatment via nonradical oxidative pathways (1O2 and electron transfer). Herein, a series of N-doped carbon nanosponges have been designed and synthesized by calcination of organic porphyrins as efficient and metal-free nanocatalysts for activating peroxymonosulfate (PMS) on acid orange 7 (AO7) degradation via a nonradical pathway. In this work, the key point of this strategy is the choice of substituent groups (including –OH, –COOH, and –NO2) on 5,10,15,20-tetraphenylporphyrin (TPP), which could serve both the heteroatom-doped source and the morphological conditioning agent. Further studies reveal that the doping of the N atom in carbon nanosponges could greatly improve their catalytic performance for activating PMS on AO7 degradation by regulating the morphology and physicochemical properties. The quenching tests and EPR analysis verified that 1O2, which contributed to 74.0% of total AO7 degradation, is selectively produced from the TPP-NO2-800/PMS system without any radicals (e.g., SO4•–, O2•–, and HO•). The minor contribution (26.0%) for AO7 elimination is probably attributed to electron transfer between AO7 and PMS. [ABSTRACT FROM AUTHOR]

Background Since effective antiviral drugs for COVID-19 are still limited in number, the exploration of compounds that have antiviral activity against SARS-CoV-2 is in high demand. Porphyrin is potentially developed as a COVID-19 antiviral drug. However, its low solubility in water restricts its clinical application. Reconstruction of porphyrin into carbon dots is expected to possess better solubility and bioavailability as well as lower biotoxicity. Methods and results In this study, we investigated the antiviral activity of porphyrin and porphyrin-derived carbon dots against SARS-CoV-2. Through the in silico analysis and assessment using a novel drug screening platform, namely dimer-based screening system, we demonstrated the capability of the antivirus candidates in inhibiting the dimerization of the C-terminal domain of SARS-CoV-2 Nucleocapsid. It was shown that porphyrin-derived carbon dots possessed lower cytotoxicity on Vero E6 cells than porphyrin. Furthermore, we also assessed their antiviral activity on the SARS-CoV-2-infected Vero E6 cells. The transformation of porphyrin into carbon dots substantially augmented its performance in disrupting SARS-CoV-2 propagation in vitro. Conclusions Therefore, this study comprehensively demonstrated the potential of porphyrin-derived carbon dots to be developed further as a promisingly safe and effective COVID-19 antiviral drug. [ABSTRACT FROM AUTHOR]

A novel approach was used to synthesize the 5,10,15,20-tetrakis (p-thiophenol) porphyrin (TPTH-P) (2), which involved the demethylation of tetra (p-anisole) porphyrin (1) in the presence of ZnCl2 as a catalyst and DMF as a solvent at 100 °C. The demethylation step was followed by an acidification step with concentrated H2SO4 to yield the desired TPTH-P (2) in an almost quantitative yield (95%). The chemical structure of the synthesized porphyrin thiol (TPTH-P) (2) was verified through spectroscopic techniques (NMR, IR, UV-Vis). The catalytic activity of TPTH-P in the hydrogen evolution reaction (HER) was investigated in 0.1 M of H2SO4 and 1 M of KNO3. A self-assembled monolayer (SAM) of TPTH-P was formed on a gold electrode. The immersion time during SAM formation and the electrochemical activation cycles in H2SO4 were found to be important to enhancing the activity of the Au-TPTH-P electrode in the HER. Contact angle measurements and electrochemical techniques, including cyclic voltammetry (CV), linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS), and chronoamperometry, were used to characterize and evaluate the electrochemical activities of the SAM. [ABSTRACT FROM AUTHOR]

To improve bacterial photodynamic inactivation (PDI), this work analyzes the photodynamic effect caused by the combination of photosensitizers (PSs) on two bacterial models and different growth mode. Simultaneous administration of PSs from different families, zinc(II) 2,9,16,23-tetrakis[4-(N-methylpyridyloxy)]phthalocyanine (ZnPPc4+), 5,10,15,20-tetra(4-N,N,N-trimethylammonium phenyl)porphyrin (TMAP4+), meso-tetrakis(9-ethyl-9-methyl-3-carbazoyl)chlorin (TEMCC4+) and 5,10,15,20-tetrakis[4-(3-N,N-dimethylaminopropoxy)phenyl] chlorin (TAPC) was investigated against Staphylococcus aureus and Escherichia coli, in planktonic form, biofilm and growth curve. Various PSs combinations showed greater inactivation compared to when used separately under the same conditions but at twice the concentration. However, differences were found in the effectiveness of the PSs combinations on Gram positive and negative bacteria, as well as in planktonic or biofilm form. Likewise, the combination of three PSs completely stopped E. coli growth under optimal nutritional conditions. PSs combination allows extending the range of light absorption by agents that absorb in different areas of the visible spectrum. Therefore, PDI with combined PSs increases its antimicrobial capacity using agents' concentrations and light fluences lower than those necessary to cause the same effect as single PS. These advances represent a starting point for future research on the potentiation of PDI promoted by the combined use of PSs. [ABSTRACT FROM AUTHOR]

Tetraphenylethylene (TPE)‐conjugated porphyrin TPE‐ZnPF is synthesized in high yield and characterized by single‐crystal X‐ray diffraction. The propeller‐shaped TPE groups not only enable exceptional aggregation‐induced emission (AIE) in the solid state but also abolish the strong π‐π stacking of porphyrin moieties and thus prohibit aggregation‐caused quenching (ACQ). TPE‐ZnPF aggregates feature long‐lived photoexcited states, which subsequently suppress non‐radiative decay channels and enhance emission intensity. Moreover, its aggregates show more efficient light‐harvesting ability due to the Förster resonance energy transfer from the TPE energy donor to the porphyrin core energy acceptor, well‐defined nanosphere morphology, and more efficient photoinduced charge separation than the porphyrin Ph‐ZnPF, which possesses ACQ and agglomerated morphology. As a result, an excellent photocatalytic hydrogen evolution rate (ηH2) of 56.20 mmol g‒1 h‒1 is recorded for TPE‐ZnPF aggregates, which is 94‐fold higher than that of the aggregates of Ph‐ZnPF (0.60 mmol g‒1 h‒1) without the TPE groups. [ABSTRACT FROM AUTHOR]

Porous organic polymers (POPs) are a class of materials that combine the properties of both polymers and porosity. They are characterized by their network structure composed of repeating organic units, which form pores or cavities throughout the material. Owing to their unique features including tunable porosity, abundant accessible active sites and synthetically control ability, POPs have been widely employed in the fields of catalysis, adsorption, and biomedicine. The incorporation of porphyrin building units into POPs endows POPs with unique structural characteristics and excellent optical properties. In this work, the aldehyde porphyrin with polyethylene glycol chain was successfully synthesized with good hydrophilicity, which was then reacted with tetrakis(4-aminophenyl) methane to construct the porphyrin-based porous organic polymers. The porphyrin-based POPs was then metallized to yield iron-containing porous organic polymers (Fe-POPs), which could catalyze the transformation of colorless substrate (3,3′,5,5′-tetramethylbenzidine (TMB)) to a blue product (ox-TMB) in the presence of hydrogen peroxide (H2O2). Upon the addition of the ascorbic acid (AA) to the aforementioned system, the blue solution faded gradually to colorless. Based on this phenomenon, a rapid and sensitive colorimetric assay for the measurement of H2O2 and AA was developed using Fe-POPs as mimetic enzyme. Fe-POPs was then successfully applied in real samples to detect AA with high accuracy. As a potential peroxidase mimic, Fe-POPs demonstrated the benefits of excellent stability and catalytic efficiency, which presented the promising application in the area of biocatalysis and biosensing. [ABSTRACT FROM AUTHOR]

Modulating the surface charge transport behavior of hole transport materials (HTMs) would be as an potential approach to improve their hole mobility, while yet realized for fabricating efficient photovoltaic devices. Here, an oxygen bridged dimer‐based monoamine FeIII porphyrin supramolecule is prepared and doped in HTM film. Theoretical analyses reveal that the polaron distributed on dimer can be coupled with the parallel arranged polarons on adjacent dimers. This polaron coupling at the interface of supramolecule and HTM can resonates with hole flux to increase hole transport efficiency. Mobility tests reveal that the hole mobility of doped HTM film is improved by 8‐fold. Doped perovskite device exhibits an increased efficiency from 19.8 % to 23.2 %, and greatly improved stability. This work provides a new strategy to improve the mobility of HTMs by surface carrier modulation, therefore fabricating efficient photovoltaic devices. [ABSTRACT FROM AUTHOR]

Since the development of the first method for porphyrin synthesis by Rothemund in 1935, porphyrin derivatives have been widely investigated and have played an essential role in chemical sciences. Most synthetic routes of porphyrins involve oxidative aromatization. Herein, we present a synthetic method to produce ABCD‐porphyrins, including chiral ones, through a one‐pot reaction involving "coordination, cyclization, and dehydrative aromatization" using a mono‐dipyrrinatoPt(II)Cl(COE) (COE=cyclooctene) complex as a platinum template. [ABSTRACT FROM AUTHOR]

A new fluorinated manganese porphyrin, (Mn‐TPP‐p‐CF3) is reported capable of providing, based on the Mn(III)/Mn(II) equilibrium, dual 1H relaxivity and 19F NMR response to redox changes. The physical‐chemical characterization of both redox states in DMSO‐d6/H2O evidenced that the 1H relaxometric and 19F NMR properties are appropriate for differential redox MRI detection. The Mn(III)‐F distance (dMn−F=9.7–10 Å), as assessed by DFT calculations, is well tailored to allow for adequate paramagnetic effect of Mn(III) on 19F T1 and T2 relaxation times. Mn‐TPP‐p‐CF3 has a reversible Mn(II)/Mn(III) redox potential of 0.574 V vs. NHE in deoxygenated aqueous HEPES/ THF solution. The reduction of Mn(III)‐TPP‐p‐CF3 in the presence of ascorbic acid is slowly, but fully reversed in the presence of air oxygen, as monitored by UV‐Vis spectrometry and 19F NMR. The broad 1H and 19F NMR signals of Mn(III)‐TPP‐p‐CF3 disappear in the presence of 1 equivalent ascorbate replaced by a shifted and broadened 19F NMR signal from Mn(II)‐TPP‐p‐CF3. Phantom 19F MR images in DMSO show a MRI signal intensity decrease upon reduction of Mn(III)‐TPP‐p‐CF3, retrieved upon complete reoxidation in air within ~24 h. 1H NMRD curves of the Mn(III)/(II)‐TPP‐p‐CF3 chelates in mixed DMSO/water solvent have the typical shape of Mn(II)/Mn(III) porphyrins. [ABSTRACT FROM AUTHOR]

During transition into a dormant state, Mycolicibacterium (Mycobacterium) smegmatis cells are able to accumulate free porphyrins that makes them sensitive to photodynamic inactivation (PDI). The formation of dormant cells in a liquid medium with an increased concentration of magnesium (up to 25 mM) and zinc (up to 62 µM) resulted in an increase in the total amount of endogenous porphyrins in dormant M. smegmatis cells and their photosensitivity, especially for bacteria phagocytosed by macrophages. To gain insight into possible targets for PDI in bacterial dormant mycobacterial cells, a proteomic profiling with SDS gel electrophoresis and mass spectrometry analysis were conducted. Illumination of dormant forms of M. smegmatis resulted in the disappearance of proteins in the separating SDS gel. Dormant cells obtained under an elevated concentration of metal ions were more sensitive to PDI. Differential analysis of proteins with their identification with MALDI-TOF revealed that 45.2% and 63.9% of individual proteins disappeared from the separating gel after illumination for 5 and 15 min, respectively. Light-sensitive proteins include enzymes belonging to the glycolytic pathway, TCA cycle, pentose phosphate pathway, oxidative phosphorylation and energy production. Several proteins involved in protecting against oxygen stress and protein aggregation were found to be sensitive to light. This makes dormant cells highly vulnerable to harmful factors during a long stay in a non-replicative state. PDI caused inhibition of the respiratory chain activity and destroyed enzymes involved in the synthesis of proteins and nucleic acids, the processes which are necessary for dormant cell reactivation and their transition to multiplying bacteria. Because of such multiple targeting, PDI action via endogenous porphyrins could be considered as an effective approach for killing dormant bacteria and a perspective to inactivate dormant mycobacteria and combat the latent form of mycobacteriosis, first of all, with surface localization. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) have emerged as a promising platform for photocatalysts. Their crystalline porous nature allows comprehensive mechanistic studies of photocatalysis, which have revealed that their general photophysical parameters, such as light absorption ability, electronic band structure, and charge separation efficiency, can be conveniently tailored by structural modifications. However, further understanding of the relationship between structure‐property‐activity is required from the viewpoint of charge‐carrier transport, because the charge‐carrier property is closely related to alleviation of the excitonic effect. In the present study, COFs composed of a fixed cobalt (Co) porphyrin (Por) centered tetraamine as an acceptor unit with differently conjugated di‐carbaldehyde based donor units, such as benzodithiophene (BDT), thienothiophene (TT), or phenyl (TA), were synthesized to form Co‐Por‐BDT, Co‐Por‐TT, or Co‐Por‐TA, respectively. Their photocatalytic activity for reducing carbon dioxide into carbon monoxide was in the order of Co‐Por‐BDT>Co‐Por‐TT>Co‐Por‐TA. The results indicated that the excitonic effect, associated with their charge‐carrier densities and π‐conjugation lengths, was a significant factor in photocatalysis performance. [ABSTRACT FROM AUTHOR]

The role of the molecular structure in the formation of the bathochromic shift of the S0 → S1 transition for a family of N-substituted porphine derivatives was studied. Molecular conformations of porphine, four of its N-substituted derivatives, and two model porphines with selected fixed bond angles and lengths in the macrocycles were optimized, the energies of the molecular orbitals were determined, and electronic absorption spectra were calculated using quantum-chemistry methods. It was found that N-substitution led to significant pyramidalization of the nitrogen atom. The degree of hybridization λ2 of the N atom depended on the volume of the N-substituent and reached a value of λ2 = 2.729 in porphyrin H(N–CCl3)P. The degree of hybridization λ2 of the N atom was established as the factor determining the energy of the long-wavelength S0 → S1 transition because the conjugation along the inner Ca–N–Ca fragment of the pyrrole ring decreased upon pyramidalization of the N atom while π-conjugation via the outer Ca–Cb–Cb–Ca fragment, which led to an increase in the size of the conjugated π-system, simultaneously strengthened. The tilt of the N-substituted pyrrole ring relative to the macrocycle mean plane and the electron-donating/electron-withdrawing properties of the N-substituents did not directly affect the bathochromic shift of the S0 → S1 transition. [ABSTRACT FROM AUTHOR]

The photophysical properties of Cu(II) complexes with 5,10,15,20-meso-tetrakis(phenyl)porphyrin and 5,10,15,20-meso-tetrakis(N-methylpyridium-4-yl)porphyrin are examined via the luminescence and femtosecond time-resolved absorbance methods, respectively. These studies are supported by DFT and TD-DFT calculations, which highlight the important role played by ligand-to-metal charge-transfer states in directing the system toward either intersystem crossing to the triplet hypersurface or coordinative expansion to a five-coordinate quasi-stable intermediate. The latter processes occur when the porphyrin is photolyzed in the presence of suitably located Lewis bases. Femtosecond time-resolved absorbance measurements of Cu(II)-5,10,15,20-meso-tetrakis(N-methylpyridium-4-yl)porphyrin confirm that the coordinative expansion in water occurs in approximately 700 fs, while crossing to the triplet hypersurface takes approximately 140 fs in the same solvent. These processes are mutually exclusive, although both can occur simultaneously depending on the environment of the porphyrin. The ratio of the two processes depends on the relative orientation of the Lewis base with respect to the copper atom at the time of excitation. As a consequence, copper porphyrins such as these are excellent probes in the environment of the porphyrin and can be used to identify the location of the porphyrin when interacting with DNA fragments. [ABSTRACT FROM AUTHOR]

Bright pink-orange-red photoluminescent (fluorescent and/or phosphorescent) fur is being found in an increasing number and diversity of mammal species. With the molecules causing these colours of photoluminescent emission suspected to be mostly photosensitive porphyrins, degradation from light exposure is an unquantified contributor to false negatives in museum-based surveys. I tested the resistance of pink photoluminescent bandicoot, Peramelidae, fur to exposure to natural sunlight and artificial laboratory lighting. Photoluminescence underwent visibly noticeable photobleaching in two minutes of direct sun exposure, or a few hours when exposed to indoor lighting. The fleeting nature of porphyrins means that an accurate representation of pink-orange-red photoluminescence should not be expected in specimens that have been exposed to light, whether in life, post-mortem, during taxidermy or on display. [ABSTRACT FROM AUTHOR]

Opinion Statement : Photodynamic therapy (PDT) has garnered increasing attention in cancer treatment because of its advantages such as minimal invasiveness and selective destruction. With the development of PDT, impressive progress has been made in the preparation of photosensitizers, particularly porphyrin photosensitizers. However, the limited tissue penetration of the activating light wavelengths and relatively low light energy capture efficiency of porphyrin photosensitizers are two major disadvantages in conventional photosensitizers. Therefore, tissue penetration needs to be enhanced and the light energy capture efficiency of porphyrin photosensitizers improved through structural modifications. The indirect excitation of porphyrin photosensitizers using fluorescent donors (fluorescence resonance energy transfer) has been successfully used to address these issues. In this review, the enhancement of the light energy capture efficiency of porphyrins is discussed. [ABSTRACT FROM AUTHOR]

The possibility of the formation of supramolecular hybrids based on two photosensitizers, an octahedral molybdenum(II) iodide cluster with six terminal isonicotinate ligands (Bu4N)2[{Mo6I8}(OOC–C5H4N)6] (PyMoC, C) and A4-type zinc(II) porphyrin (ZnTPP, P), has been demonstrated. Spectrophotometric and NMR titration methods have shown that the formation of CPn complexes (n = 1–6) occurs in solutions of noncoordinating chlorinated solvents due to the formation of metal–N-ligand coordination bonds between the components. The use of an octahedral cluster as a hexatopic N-ligand and the lability of the Zn···NPy bonds together lead to the formation of a series of CPn complexes (n = 1–6), which are in dynamic equilibrium in solution. Nevertheless, conditions have been selected to isolate single crystals of individual forms CP4 + 2 and CP6 + 2, and their structures have been determined by X-ray diffraction analysis. The PyMoC cluster turns out to coordinate four or six ZnTPP molecules, respectively, while both structures contain two "extramolecules" of zinc(II) porphyrin bound to the cluster via hydrogen bonds involving the oxygen atoms of the isonicotinate groups and protons of water axially coordinated to the porphyrin metal center. [ABSTRACT FROM AUTHOR]

In the continuation of our sustained interest in porphyrin-based dendrimers and their use as luminescent photosensitizers for two-photon photodynamic therapy (2P-PDT), we wondered about the effect of changing the connectors in our macromolecular structures. We also wanted to initiate preliminary studies on meso-tetraarylporphyrins decorated with more electron-releasing arms. Thus, various meso-tetrafluorenylporphyrin-cored star-shaped and dendrimeric derivatives have been synthesized and characterized, as well as their zinc(II) complexes. In the new dendrimeric derivatives, the peripheral fluorenyl units of the dendrons are linked to the inner core either by N-phenylcarbazole (CCbz) or triphenylamine (CTpa) connectors instead of the more classic 1,3,5-phenylene (CPh) linkers previously used by us. Selected linear and non-linear optical (LO and NLO) properties were then determined for these compounds via absorption or emission studies and by two-photon excited fluorescence (TPEF) measurements. It was found that the CCbz-containing dendrimer, which has the most rigid structure, exhibits a significantly lower two-photon absorption (2PA) cross-section than its CTpa analog, presenting a more flexible structure while rather similar luminescence and singlet oxygen activation quantum yields are found for both. The origin of this unexpected discrepancy is briefly discussed based on our photophysical data. It is then demonstrated that the latter dendrimer also outperforms several closely related dendrimers in terms of 2PA action cross-section and 2PA-oxygen sensitization, making its molecular architecture quite appealing for developing new 2PA photosensitizers suited to theranostic uses. [ABSTRACT FROM AUTHOR]

In this research, first, the cobalt (III) complex of 20,15,10,5-tetrakis (tetra(4-carboxyphenol)) porphyrin (Co-THPBP) was synthesized and its terminal acidic groups were chlorinated using thionyl chloride. Then, in order to stabilize the desired complex on the chitosan polymer substrate, the chlorinated cobalt-porphyrin complex was modified using protected 4-aminophenol, and as well as by deprotection of the terminal hydroxyl group of 4-aminophenol, the modified complex was attached to the chitosan polymer substrate. The prepared compounds were characterized using Fourier transform infrared spectroscopy (FT-IR), 1H NMR, Ultraviolet–visible spectroscopy (UV-Vis), scanning electron microscope (SEM), Diffuse Reflectance Spectroscopy (DRS). The prepared compound was applied for the photocatalytic removal of methylene blue in the presence of visible light. The results confirmed that the presence of chitosan polymer substrate has a significant effect on increasing the photodegradation of methylene blue dye.

Among all the available approaches in organic synthesis, the “click chemistry” protocol is very common nowadays to covalently connect two diverse moieties in a single framework. Therefore, this review focuses on the synthesis and photophysical studies of β- and meso-substituted and 1,2,3-triazole-fused porphyrin conjugates. All of the porphyrin conjugates discussed here are synthesized via a copper(I)-catalyzed Huisgen 1,3-dipolar cycloaddition reaction between an azide and a terminal alkyne, also popular as "click reaction" or CuAAC reaction. Moreover, the 1,2,3-triazole ring also serves as a spacer and an electron transfer bridge between the porphyrin and the attached chromophores. In order to provide a critical overview of the synthesis and properties of various porphyrin-triazole hybrids, this review will discuss some of the key reactions involved in the preparation of triazole-linked porphyrin conjugates.

Locking nonequilibrium shapes of liquids into targeted architectures by interfacial jamming of nanoparticles is an emerging area in material science. 5,10,15,20-tetrakis(4-sulfonatophenyl) porphyrin (H6 TPPS) shows three different aggregation states that present an absorption imaging platform to monitor the assembly and jamming of supramolecular polymer surfactants (SPSs) at the liquid/liquid interface. The interfacial interconversion of H6 TPPS, specifically H4 TPPS2- dissolved in water, from J- to an H-aggregation was induced by strong electrostatic interactions with amine-terminated polystyrene dissolved in toluene at the water/toluene interface. This resulted in color-tunable liquids due to interfacial jamming of the SPSs formed between H4 TPPS2- and amine-terminated polystyrene. However, the formed SPSs cannot lock in nonequilibrium shapes of liquids. In addition, a self-wrinkling behavior was observed when amphiphilic triblock copolymers of PS-block-poly(2-vinylpyridine)-block-poly(ethylene oxide) were used to interact with H4 TPPS2- . Subsequently, the SPSs formed can lock in nonequilibrium shapes of liquids.

Iron porphyrins are known to provide CH4 as an eight-electron reduction product of CO2 in a photochemical reaction. However, there are still some aspects of the reaction mechanism that remain unclear. In this study, we synthesized iron porphyrin dimers and carried out the photochemical CO2 reduction reactions in N,N-dimethylacetamide (DMA) containing a photosensitizer in the presence of 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (BIH) as an electron donor. We found that, despite a low catalytic turnover number, CH4 was produced only when these porphyrins were facing each other. The close proximity of the cyclic dimers, distinguishing them from a linear Fe porphyrin dimer and monomers, induced multi-electron CO2 reduction, emphasizing the unique role of their structural arrangement in CH4 formation.

We present a Raman spectroscopy study of the vibrational properties of free-base meso-tetra(4-pyridyl) porphyrin polycrystals under various temperature and hydrostatic pressure conditions. The combination of experimental results and Density Functional Theory (DFT) calculations allows us to assign most of the observed Raman bands. The modifications in the Raman spectra when excited with 488 nm and 532 nm laser lights indicate that a resonance effect in the Qy band is taking place. The pressure-dependent results show that the resonance conditions change with increasing pressure, probably due to the shift of the electronic transitions. The temperature-dependent results show that the relative intensities of the Raman modes change at low temperatures, while no frequency shifts are observed. The experimental and theoretical analysis presented here suggest that these molecules are well represented by the C2v point symmetry group.

Access to clean drinking water is a basic requirement, and eliminating pollutants from wastewater is important for saving water ecosystems. The porous structure and surface characteristics of metal–organic frameworks (MOFs) can function as a perfect scaffold for removing toxic compounds from wastewater. Porphyrins are promising building blocks for constructing MOFs. Porphyrin-based metal–organic frameworks (P-MOFs) have been fabricated using porphyrin ligands, metal clusters, or ions. These materials can harvest light from a wide region of the solar spectrum, and their framework morphology and physicochemical properties can be controlled by changing their peripheral subunits or metal ions. These porous crystalline materials have generated interest because of their distinctive characteristics, including large permanent porosity, interesting surface morphology, broad conformational diversity, high photostability, and semiconducting nature. This article discusses the recent progress and usefulness of P-MOFs. The fabrication procedures of P-MOFs are discussed, followed by the adsorptive and photocatalytic removal of contaminants from wastewater. The relationships between the geometries of P-MOFs and their light-harvesting and charge-transfer mechanisms for the photocatalytic degradation of pollutants are highlighted. Finally, some future perspectives and obstacles in the photodegradation usage of P-MOFs are discussed, along with feasible research directions to standardize efficient photocatalysts for improved photodegradation for water treatment.

In this study, dinuclear and tetranuclear arene ruthenium porphyrins were synthesized and assessed for their potential as photosensitizers (PSs) in photodynamic therapy (PDT) using the Colo205 colon cancer cell line as a model system. Reactive oxygen species (ROS) production, cellular uptake, impact on cell viability, and mechanisms of cell death induced by the synthesized compounds were comprehensively investigated. Our results revealed that the number of arene ruthenium units, as well as zinc (Zn) metalation of the porphyrin core, significantly influenced ROS production and increased it two-folds compared to the Zn-free analogs. The uptake of tetra-substituted Zn-porphyrins by the cancer cells increased to 2.8 nmol/106 cells compared to 0.6 nmol/106 cells of the disubstituted Zn-free and Zn-chelating porphyrins. The anticancer photo-activity of the complexes, where the percentage of metabolic activity of disubstituted Zn-porphyrins decreased to 26% when Zn was inserted, was compared to disubstituted Zn-free analogs. A further decrease in metabolic activity was observed, when the number of arene ruthenium units increased in the tetra-substituted Zn-porphyrins and tetra-substituted Zn-free compounds, reaching 4% and 14% respectively. Moreover, the percentage of apoptotic cell deaths increased to 40% when Zn was inserted into disubstituted porphyrins, compared to disubstituted Zn-free analog, and 50% when the number of arene ruthenium units increased. Overall, the tetra-substituted Zn chelating porphyrins exhibited the highest PDT efficiency, followed by the di-substituted Zn-porphyrins. These findings underscore the importance of structural design in optimizing the efficacy of arene ruthenium porphyrins as PSs for PDT, offering valuable insights for the development of targeted cancer therapeutics.

This study investigated the adsorption of CO2 molecules on transition metal ions (TM) porphyrins induced carbon nanocone (TM-PICNC) (TM = Sc2+, Ti2+, V2+, Cr2+, Fe2+, Co2+, Ni2+, Cu2+, and Zn2+) using density functional theory (DFT) to determine the stabilities, energetic, structural, and electronic properties. The results showed that the CO2 molecule is adsorbed on TM-PICNC with adsorption energies ranging from 0.03 to −12.12 kcal/mol. The weak interactions of CO2 gas with Cr, Ni, Cu, and Zn-PICNC were observed, while strong adsorption was found on Sc, Ti, and V-PICNC. The Ti, V, and Cr-PCNC structures were shown to have a suitable energy gap (Eg) for sensing ability because of the effective and physical interaction between these structures and CO2 gas, leading to a short recovery time. DFT calculations also revealed that V-PCNC had a high %ΔEg (about %56.79) and hence high sensitivity to CO2 gas, making it a promising candidate for having good sensing ability to CO2 gas in presence of O2 and H2O gas.

Abstract Tetraphenylethylene (TPE)‐conjugated porphyrin TPE‐ZnPF is synthesized in high yield and characterized by single‐crystal X‐ray diffraction. The propeller‐shaped TPE groups not only enable exceptional aggregation‐induced emission (AIE) in the solid state but also abolish the strong π‐π stacking of porphyrin moieties and thus prohibit aggregation‐caused quenching (ACQ). TPE‐ZnPF aggregates feature long‐lived photoexcited states, which subsequently suppress non‐radiative decay channels and enhance emission intensity. Moreover, its aggregates show more efficient light‐harvesting ability due to the Förster resonance energy transfer from the TPE energy donor to the porphyrin core energy acceptor, well‐defined nanosphere morphology, and more efficient photoinduced charge separation than the porphyrin Ph‐ZnPF, which possesses ACQ and agglomerated morphology. As a result, an excellent photocatalytic hydrogen evolution rate (ηH2) of 56.20 mmol g‒1 h‒1 is recorded for TPE‐ZnPF aggregates, which is 94‐fold higher than that of the aggregates of Ph‐ZnPF (0.60 mmol g‒1 h‒1) without the TPE groups.

Abstract A series of triazole‐bearing oligo(ethylene glycol)‐strapped zinc porphyrins (PZn4EG and PZn5EG) have been prepared as artificial ion‐binding receptors. Both PZn4EG and PZn5EG exhibit UV/Vis absorption changes in a solvent‐dependent manner upon titration with halides and alkali metal ions. In tetrahydrofuran, both PZn4EG and PZn5EG exhibit spectral shifts upon the addition of halide ions through axial coordination, whereas the absorption does not change upon the addition of alkali metal ions. On the other hand, in 10% MeCN/CHCl3, the UV/Vis absorption spectra of both PZn4EG and PZn5EG do not change upon the addition of an excess amount of halide ions; however, PZn4EG and PZn5EG show selective alkali metal ion‐binding properties in this solvent. PZn4EG and PZn5EG display dramatic color changes and spectral shifts upon the addition of Li+ and K+, respectively. Because of the dramatic color changes that occurred upon binding, the determination of alkali metal ions would be possible.

An oriented cylindrical mesoporous silica (MPS) film has been synthesized on rubbing-treated (rubbed) polyimide (PI), which has the potential to be used as a surface-modified technology for biomedical catheters. However, the oriented cylindrical MPS film lacked isotropic mechanical properties because the cylindrical mesostructures were uniaxially oriented. Thus, it is possible to improve the isotropic properties of cylindrical MPS films by cross-laminating their cylindrical mesostructure. In this study, an orthogonally stacked and cylindrically oriented MPS film with two layers (2-L-MPS) was successfully synthesized through the following processes: (i) The 1st-layer-oriented MPS film was synthesized on the 1st-layer-rubbed PI film. (ii) The 2nd-layer-rubbed PI film was coated on the 1st-layer-oriented MPS film where the rubbing direction was perpendicular to that of the 1st-layer-rubbed PI film. (iii) The 2nd-layer-oriented MPS film was synthesized on the 2nd-layer-rubbed PI film. As for the 2-L-MPS film, it was proved that the orthogonally stacked and cylindrically oriented MPS film with 2-layer from the φ-scan XRD patterns, and the pore diameters of the 1st- and 2nd-layer-oriented MPS films were 3.7 and 4.8 nm from the Barrett–Joyner–Halenda (BJH) pore size distributions. The isotropic mechanical property of the 2-L-MPS film is thought to be enhanced by orthogonal stacking. Subsequently, the 2-L-MPS films were immersed into α,β,γ,δ-tetrakis-(1-methylpyridinium-4-yl)-porphyrin p-toluenesulfonate (TMPyP) solutions with different concentrations, and the structures of the immersed 2-L-MPS films were evaluated and the adsorption states of TMPyP were investigated. The mesostructures of the 2-L-MPS films were still maintained after being immersed in the TMPyP solutions. Moreover, 2-L-MPS showed the different molecular adsorption states of TMPyP at the 1st- and 2nd-layer-oriented mesopores because of the difference in the pore size between each MPS layer. In the future, it is expected to be applied as a surface modification technology to endue biomedical materials such as PI catheters with excellent mechanical properties and oriented cell adhesion properties. Moreover, it has the potential to be used as a coating material that loads two drug molecules with different molecular diameters and releases them in a sustained manner by utilizing the difference in the pore size between the 1st- and 2nd-layer-oriented mesopores. [ABSTRACT FROM AUTHOR]