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Photocatalyst adsorbents are an appealing group of materials for environmental applications. Herein, we study a new simple, inexpensive, yet very effective adsorbent photocatalyst based on porphyrin immobilized activated carbon-decorated polyacrylonitrile, InP(PAN/AC), for removal of methylene blue dye and Ciprofloxacin in water under Xe-lamp and sunlight irradiation (the latter for Ciprofloxacin only). Our results shed light on developing the most effective and sustainable adsorbent photocatalysts that can easily be industrialized due to the ease of preparation through electrospinning coupled with the readily available preparation materials. After five cycles, the InP(PAN/AC) maintained high methylene dye removal efficiency and structural integrity. Significantly, we propose the coordinated contribution of singlet oxygen and hydroxyl radical in the photodegradation process and highlight the importance of such an integrated system with adsorption and photodegradation capabilities for water treatment.

Antimicrobial resistance is a matter of concern to all biological systems. This work investigates the antimicrobial activity of porphyrins conjugated to pristine graphene quantum dots (pGQDs) through non-covalent linking. A novel In 5,10,15,20-tetrakis[4-(benzyloxy) phenyl] porphyrin (InTBnOPP) was synthesized and fully characterized. The photophysicochemical parameters of H2TBnOPP, ZnTBnOPP, InTBnOPP, and their conjugates were investigated. It was found that pGQDs improved the singlet oxygen quantum yield upon conjugation with the porphyrins. pGQDs-InTBnOPP had a higher singlet oxygen quantum yield of 0.80 when compared to all other conjugates. Porphyrins are well-known photosensitizers for photodynamic antimicrobial chemotherapy (PACT); this was also confirmed by pGQDs-ZnTBnOPP and pGQDs-InTBnOPP which completely inhibited both S. aureus and E. coli with log reduction values of 9.42 and 8.59 with an irradiated time of 5 and or 10 min, respectively. The porphyrins alone had significant antibacterial activities. In general, the obtained results demonstrate a good response of these nanoconjugates against Gram (+) and Gram (-) bacteria.

The optical limiting properties of three meso-pyridyl-distyrylBODIPY dyes with differing alkyl substitution patterns at the 2,6- and 1,7-positions on the pyrrole moieties are investigated. Styryl groups are introduced at the 3,5-positions to form dyes with strong donor-[Formula: see text]-acceptor (D-[Formula: see text]-A) properties. Favorable optical limiting properties are obtained for all three dyes, with the highest second-order hyperpolarizability obtained for a dye that is unsubstituted at both the 2,6- and 1,7-positions suggesting that the optical limiting properties are enhanced when the meso-aryl ring can freely rotate into the plane of the BODIPY core.

Research on recently reported Sn(iv) porphyrinoids, including corroles, chlorins and N-confused porphyrins, focusing primarily on their photodynamic therapy (PDT) and photodynamic antimicrobial chemotherapy (PACT) activity properties is reviewed.

The ease of functionalization of BODIPY dyes provides scope for preparing pH indicators by introducing suitable functional groups. In this work, two dimethylamino substituted BODIPY dyes 3 and 4 with styryl and phenylbuta-1,3-dienyl groups introduced at the 3,5-positions were synthesized, characterized, and studied for use as pH indicators. Incorporation of the electron-rich vinylene substituents yielded dyes that absorb in the NIR region with emission wavelengths of 796 and 797 nm for 3 and 4, respectively, in dimethylsulfoxide (DMSO). Time-dependent density functional theory (TD-DFT) calculations were performed to study the effect of adding an extra alkene bond in 4 on the photophysical properties. The extra alkene bond in 4 resulted in a 3 nm shift in the main NIR region absorption band, lower molar extinction coefficient values, higher emission wavelength, and a decrease in fluorescence quantum yield in all solvents studied. Upon protonation of the amino groups, a large blue shift is observed in both the absorption and emission wavelengths, along with an increase in the fluorescence quantum yields and longer fluorescence lifetimes. The [Formula: see text] values for 3 and 4 were estimated to be 2.9 (± 0.05) and 1.2 (± 0.05), respectively.

The photodynamic antimicrobial chemotherapy (PACT) activities of four meso-pentafluorophenylBODIPY dyes were studied against Staphylococcus aureus to identify structure-property relationships related to the introduction of different substituents on the BODIPY core. 1,3,5,7-Tetramethyl dyes with bromine and iodine atoms at the 2,6-positions (2a and 3a) were synthesized and characterized along with 3,5-dimethyl dyes that were either tetrabrominated at the 1,2,6,7-positions (2b) or diiodinated (3b) at the 2,6-positions. The incorporation of iodine atoms on the BODIPY core at the 2,6-positions enhanced the PACT activity relative to those of the di- and tetrabrominated dyes. Replacing the methyl groups at the 1,7-positions with protons to form 3b results in greater PACT activity than is the case with 3a since the absence of steric hindrance related to methyl groups at the 1,7-positions allows the meso-aryl ring to rotate closer to the plane of the [Formula: see text]-system of the BODIPY core. The tetrabrominated dye was found to have the lowest PACT activity due to a lack of stability in solution and poor uptake by the bacteria being studied. The electron-withdrawing pentafluorophenyl group was selected to lower the dipole moment of the BODIPY core dye since poor PACT activity was observed when a 2,6-dibromo-1,3,5,7-tetramethyl BODIPY dye was prepared with a thiomethylphenyl group (2c).

In this study, novel mono- and dipyridylvinyl boron dipyrromethene dyes are prepared to compare their photodynamic antimicrobial chemotherapy (PACT) activities against Staphylococcus aureus to the corresponding core dyes. Pyridylvinyl substitution at the 3- or 3,5-positions of a meso-4-bromophenylBODIPY core dye via a Knoevenagel reaction with an aromatic 2-bromopyridinecarboxaldehyde shifts the major BODIPY spectral band to longer wavelength. The extended π-conjugation red shifts the main spectral band into the 602-618 nm region in CHCl

Novel 5-(pyridyl)-10-15-20-tris(4-bromophenyl) porphyrin (complex 1), indium metal derivative (complex 2), and quaternized derivative (complex 3) were synthesized and conjugated to graphene quantum dots (GQDs). The conjugation of the porphyrins to GQDs was through [Formula: see text]-[Formula: see text] stacking. Herein, the [Formula: see text]-[Formula: see text] stacking approach was used to avoid covalent conjugation which might compromise the intrinsic chemical and physical properties. The photodynamic activities of the proposed nanomaterials were assessed towards Staphylococcus aureus cell obliteration. The photophysical properties of the prepared complexes were also studied prior to the application. Moreover, a decrease in fluorescence lifetimes was observed upon metalation of complex 1. As anticipated, singlet oxygen quantum yield ([Formula: see text] increased notably upon heavy metal (indium) insertion and upon composite formation. Antimicrobial photodynamic therapy comparative studies were done on quaternized and unquaternized indium porphyrins conjugated to GQDs. Complex 3-GQDs exhibited the highest antibacterial activities compared to other complexes, and this was attributed to the high [Formula: see text] which plays an imperative role in photodynamic therapy applications.

In this study, we report for the first time on the photodynamic antimicrobial chemotherapy (PACT) of asymmetrical zinc(II) phthalocyanines and their conjugates with nickel tungstate (NiWO4), cobalt tungstate (CoWO4) and bismuth tungstate (Bi2WO6) nanoparticles. CoWO4, NiWO4 and Bi2WO6 were capped with glutathione and covalently linked to three asymmetrical zinc(II) phthalocyanines for PACT. The plate count method was used to investigate the effect of covalently linking asymmetrical zinc(II) phthalocyanines to nanoparticles under light (for PACT against Staphylococcus aureus) and in the dark. Both Pc complexes and the conjugates indicated minimum dark-toxicity. The conjugates showed greater antimicrobial activity against a gram-positive and drug resistant bacteria, Staphylococcus aureus, than Pc complexes alone.

Two GaIIItriarylcorroles with carbazole substitutions at 10-positions were synthesized, characterized, and their biomedical propeties were also investigated.

A Sn(iv) porphyrin with a mitochondria targeting triphenylphosphonium moiety has a high ΦΔ value (ca. 0.72) and does not aggregate in aqueous solution. The dye exhibits favorable photodynamic activity against MCF-7 cells with an IC50 value of 2.9 μM.

In this study, free-base meso 5,10,15,20-tetra(pyren-1-yl)porphyrin (H2TPyP) and its corresponding indium(III) complex (InClTPyP) were synthesized and characterized on the basis of mass spectrometry, 1H NMR spectroscopy and elemental analysis. InClTPyP was obtained in good yield by treating the free base H2TPyP with indium(III) chloride. Purification of these compounds was achieved through column chromatography using different solvent systems. Metallation of the free base to form a metallo-porphyrin afforded improved photophysical properties. There was a bathochromic shift in wavelength of absorption from the parent free base H2TPyP ([Formula: see text] = 431 nm) to metallated indium(III) complex ([Formula: see text] = 443 nm). The fluorescence quantum yield in H2TPyP was higher ([Formula: see text] = 0.131) than in InClTPyP ([Formula: see text] = 0.017) due to efficient intersystem crossing to the triplet manifold in the metallated porphyrin. Upon illumination, both H2TPyP and InClTPyP show effective dose dependent antimicrobial activity against Staphylococcus aureus with photoinactivation IC[Formula: see text] values of 27.89 and 16.67 [Formula: see text]M, respectively.

A liposome loaded‑silicon (IV) phthalocyanine (SiPc) containing naphthoquinone axial ligands as hypoxia-responsive a prodrug-like moieties (Prodrug-SiPc), is herein reported. With the help of computational methods, this study assessed the photophysical, photochemical and electrochemical redox properties of the Prodrug-SiPc to elucidate the relationship between material structure and properties. The attachment of the axial quinoid moieties endowed the Prodrug-SiPc with Type I/II photochemical and prodrug-like properties. Following liposomal encapsulation, the therapeutic efficacy of Prodrug-SiPc-liposomes was investigated against Michigan Cancer Foundation-7 (MCF-7) and Henrietta Lacks (Hela) cancer cells as in vitro cancer models and revealed that the as-synthesized Prodrug-SiPc-liposomes are potential photodynamic therapy (PDT) drug candidates. The Prodrug-SiPc-liposome takes full advantage of the hypoxic microenvironment of tumors - a side effect PDT - to trigger therapy, resulting in significantly enhanced efficacy compared to typical PDT. This work highlights the importance of multiple characteristics in designing new and effective photosensitizer candidates.

In this work, cobalt tetra phenoxy acetic acid phthalocyanine (CoTAPc) is investigated as an electron mediator, immobilization platform for an HB5 aptamer and to enhance the electrochemical signal for the detection of human epidermal growth factor receptor 2 (HER2). Furthermore, the CoTAPc was combined individually with sulphur/nitrogen doped graphene quantum dots (SNGQDs), gold nanoparticles (AuNPs) and cerium oxide nanoparticles (CeO

The synthesis and characterization of neutral zinc and indium substituted mercaptobenzothiazole substituted phthalocyanines (Pcs) and their respective cationic derivatives are presented. The phthalocyanines were further covalently linked to two differently shaped amino-functionalized ZnO nanoparticles (ZnONPs): namely nanospheres (NH

An account on the synthesis of an asymmetric cobalt phthalocyanine, 4-((2(3),16(17),23(24)-tri-tert-butylphthalocyanine-9-yl)oxy)benzoic acid cobalt (II) (complex 1) and its symmetric counterpart, 2,9,16,23-tetra-tert-butylphthalocyanine cobalt (II) (complex 2) is provided in this work. The complexes reported were applied in the electrooxidation of hydrazine with a glassy carbon electrode serving as a support for the electrocatalysts. In comparing the two, complex 1 produced the more favourable result with a higher peak current. A further assessment on the reactivity of the complexes was carried out using theoretical calculations. Using the density functional theory method, the electronic parameters including the gap between the highest occupied molecular orbital and the lowest unoccupied molecular orbital, electrophilicity (ω), electronegativity (χ), chemical softness (S) and hardness (η) were determined. The theoretical results deemed complex 1 as the more reactive structure as it had higher values for both the electronegativity and electrophilicity. The donor-acceptor hardness (ηDA) values were also found to be in alignment with the experimental results were complex 1 produced the lower oxidation potential as it had the higher ηDA value.

Three ABAB-type cobalt

Photodynamic antimicrobial chemotherapy (PACT) coupled with an antibiotic, ciprofloxacin (CIP), was investigated using two indium metallated cationic photosensitizers, a porphyrin (1) and a phthalocyanine (2). Applying PACT followed by the antibiotic treatment led to a remarkable reduction in the biofilm cell survival of two antibiotic-resistant bacterial strains, S. aureus (Gram + bacteria) and E. coli (Gram- bacteria). Treating both bacteria strains with PACT alone showed no significant activity at 32 µM with 15 min irradiation, while CIP alone exhibited a minimum biofilm inhibition concentration (MBIC) at 4 and 8 µg/mL on S. aureus and E. coli respectively following 24 h incubation. The combined treatment resulted in the complete eradication of the matured biofilms with high log

A series of tetraarylchlorins with 3-methoxy-, 4-hydroxy- and 3-methoxy-4-hydroxyphenyl meso-aryl rings (1-3-Chl) and their Sn(IV) complexes (1-3-SnChl) were synthesized and characterized so that their potential utility as photosensitizer dyes for use in photodynamic therapy (PDT) and photodynamic antimicrobial chemotherapy (PACT) can be assessed. The photophysicochemical properties of the dyes were assessed prior to in vitro PDT activity studies against MCF-7 breast cancer cells through irradiation with Thorlabs 625 or 660 nm LED for 20 min (240 or 280 mW·cm−2). PACT activity studies were performed against both planktonic bacteria and biofilms of Gram-(+) S. aureus and Gram-(−) E. coli upon irradiation with Thorlabs 625 and 660 nm LEDs for 75 min. The heavy atom effect of the Sn(IV) ion results in relatively high singlet oxygen quantum yield values of 0.69−0.71 for 1-3-SnChl. Relatively low IC50 values between 1.1−4.1 and 3.8−9.4 µM were obtained for the 1-3-SnChl series with the Thorlabs 660 and 625 nm LEDs, respectively, during the PDT activity studies. 1-3-SnChl were also found to exhibit significant PACT activity against planktonic S. aureus and E. coli with Log10 reduction values of 7.65 and >3.0, respectively. The results demonstrate that the Sn(IV) complexes of tetraarylchlorins merit further in depth study as photosensitizers in biomedical applications.

In this study, peripherally benzimidazole unit substituted ZnPc (1) and its conjugation to nitrogen doped graphene quantum dot (NGQD) as potential phthalocyanine support via π-π stacking have been presented and fully characterized. The bottom-up solution-based synthesized NGQDs was conjugated non-covalently to zinc phthalocyanine to form NGQDs-Pc nanoconjugates. The photophysical and photochemical properties of both such as absorption, fluorescence, fluorescence life time, singlet oxygen quantum yields, triplet state quantum yields and exited state lifetimes were investigated in solutions. We observed a decrease in the fluorescence quantum yields with a corresponding increase in the triplet quantum yield and singlet oxygen quantum yield of the nanoconjugates in comparison to the phthalocyanine complex alone. Photodynamic antimicrobial chemotherapy activities (PACT) of ZnPc alone and its nanoconjugate were determined towards Staphylococcus aureus.

The synthesis and characterization of tetrakis[4(4-acetlyphenoxy)phthalocyanato] cobalt (II) (1) are presented. Complex 1 together with the reported tetrakis dimethyl 5-(phenoxy)-isophthalatephthalocyaninato] cobalt (II) (2) are conjugated to carbon-based nanomaterials: graphene quantum dots (GQDs) and single-walled carbon nanotubes (SWCNTs) via π-π stacking, taking advantage of the π electrons on the graphitic structure of the nanomaterial as well as on the aromatic rings of the Co phthalocyanines (CoPcs). The electrocatalytic behaviour of the CoPcs, GQDs, SWCNTs and their respective conjugates towards the electrochemical oxidation of catechol was studied. The electrocatalytic probes were drop-dried onto the electrode surface of the glassy carbon electrode (GCE). The electrochemical oxidation of catechol was studied using cyclic voltammetry, electrochemical impedance spectroscopy and chronoamperometry. Complex 2 when linked to GQDs gave the lowest oxidation peak potentials of 0.33 V. Low catechol detection limits (LOD) of 0.057 µM was obtained for complex 2 with SWCNT. Thus, complex 2 containing more oxygen atoms outperformed complex 1 with less oxygen atoms. The CoPcs on their own showed moderate electrocatalytic behaviour, hence showing the importance of conjugating them to the carbon nanomaterials. SWCNT-based electrodes performed better than GQDs, and an improvement in the LoDs, sensitivity and the catalytic rate was observed upon conjugation.

A novel alternative route to access rhenium(V)-phthalocyanine complexes through direct metalation of metal-free phthalocyanines (H

Two A

In this research report, we prepared an electrochemical sensor based on the molecularly imprinted poly(p-aminophenol) supported by silver nanoparticles capped with 2-mercaptobenzoxazole for the selective and sensitive detection of endocrine disrupting 17-β-estradiol (E2). The electropolymerization of the functional monomer prepared the proposed molecularly imprinted polymer (MIP) composite-based sensor in the presence of E2 as a template. The recognition materials were characterized using Fourier transform infrared, cyclic voltammetry (CV), square wave voltammetry (SWV), scanning electron microscopy, energy-dispersive X-ray spectroscopy and X-ray powder diffraction techniques. The electrochemical measurements were performed by employing both CV and SWV methods. We did the optimization of critical parameters affecting the sensor performances through the experimental design and verification. The developed sensor showed a linear range from 10 pM to 100 nM with the calculated quantification and detection limits of 1.86 and 6.19 pM, respectively. The incorporation of AgNP with high electrical conductivity into the MIP matrix enhanced the sensor's performance. Furthermore, the sensor was applied to determine E2 in real water samples without any sample preconcentration steps to achieve the percent recovery of 91.87% to 98.36% and acceptable reusability and storage stability performances.

Meso-tetra(4-methylthiolphenyl)chlorin (3) and its Sn(IV) complex (3-Sn) have been synthesized and characterized. The heavy atom effects of the Sn(IV) ion and sulfur atoms result in relatively high singlet oxygen quantum yield values of 0.40 and 0.48. The photodynamic activities against MCF-7 breast cancer cells were determined through irradiation with a Thorlabs 660 nm LED for 30 min (280 mW.cm

Glass carbon electrodes (GCE) were modified with metal organic frameworks (MOFs) containing molybdenum polyoxometallates (Mo POMs) in a copper benzene tricarboxylate framework (HKUST-1). The Mo POM...

The rational design and preparation of three A2B type Co(III)triarylcorroles with push- and pull-substituents are reported. The structure-property relationships were identified by comparing their optically spectroscopic and electrochemical properties to trends predicted in DFT and TD-DFT calculations. The results demonstrate that the Co(III)triarylcorroles are highly efficient catalysts for electrocatalyzed hydrogen evolutions (HERs) and oxygen reductions (ORRs), and that their reactivity can be modulated by changing the meso-B-substituent of the Co(III)Corroles.

This work focuses on the study of the effects of the ultrasonic frequency (MHz) and power (W.cm