Design of N-heterocycle based-phthalonitrile/metal phthalocyanine-silver nanoconjugates for cancer therapies.

This study reports the anticancer properties of carbazole-containing phthalonitrile/phthalocyanine-modified silver nanoparticles for the first time. In this study, a new mono-substituted phthalonitrile namely 3-[9H-carbazole-9-ethoxy]phthalonitrile and its metal phthalocyanines {M = Zn, Co, and Mn(Cl)} were synthesized by template cyclotetramerization of phthalonitrile derivatives. The newly synthesized compounds were characterized using UV-vis, FT-IR, 1H NMR, 13C NMR, and mass spectroscopy. The resultant compounds were successfully linked to the surface of silver nanoparticles. The characterization of the surficial modification was carried out by applying the TEM technique. The cytotoxic activities of the studied nanoconjugates were tested against A549, DLD-1, and Wi38 cell lines by performing a (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) (MTT) assay with/without irradiation. Although the functionalization of silver nanoparticles increased the solubility of phthalocyanines in aqueous media, the presence of phthalonitrile/phthalocyanine derivatives on the silver nanoparticles' surface improved their biological properties. All the studied biological candidates exhibited antiproliferative activities against the cell lines. The IC50 values calculated were between 6.80 and 97.99 µM against the studied cell lines in the dark. However, the IC50 values determined were between 3.11 and 88.90 µM with irradiation. The highest IC50 values obtained were 3.11 and 3.52 µM against the DLD-1 cell line for nanoconjugates 1-AgNP and 3-AgNP, respectively. The findings indicated that the compounds may be utilized as anticancer agents after further studies.

Effect of Axial Ligand Length on Biological and Anticancer Properties of Axially Disubstituted Silicon Phthalocyanines.

In this study, three new axially disubstituted silicon phthalocyanines (SiPc1-3) and their quaternized phthalocyanine derivatives (QSiPc1-3) were prepared and characterized. The biological properties (antioxidant, antimicrobial, antibiofilm, and microbial cell viability activities) of the water-soluble silicon phthalocyanines were examined, as well. A 1 % DMSO diluted with pure water was used as a solvent in biological activity studies. All the compounds exhibited high antioxidant activity. They displayed efficient antimicrobial and antimicrobial photodynamic therapeutic properties against various microorganisms, especially Gram (+) bacteria. Additionally, they demonstrated high antibiofilm activities against S. aureus and P. aeruginosa. In addition, 100 % bacterial reduction was obtained for all the studied phthalocyanines against E. coli viable cells. Besides, the DNA cleavage and binding features of compounds (QSiPc1-3) were studied using pBR322 DNA and CT-DNA, respectively. Furthermore, the human topoisomerase I enzyme inhibition activities of compounds QSiPc1-3 were studied. Anticancer properties of the water-soluble compounds were investigated using cell proliferation MTT assay. They exhibited anticarcinogenic activity against the human colon cancer cell line (DLD-1). Compounds QSiPc1 and QSiPc3 displayed a high anticarcinogenic effect on the DLD-1 cell line. The obtained results indicated that all the studied compounds may be effective biological agents and anticancer drugs after further investigations.

Anticancer and biological properties of new axially disubstituted silicon phthalocyanines.

This study reports the synthesis of three novel axially disubstituted silicon phthalocyanines (1-3-Si) and their quaternized phthalocyanines (1-3-QSi). The resulting compounds were characterized by applying spectroscopic techniques including 1H NMR, FT-IR, UV-vis, and mass spectroscopy. The biological properties of compounds 1-3-QSi, including DNA cleavage activities, DNA binding modes, and topoisomerase enzyme inhibition activities, were investigated using agarose gel electrophoresis. pBR322 plasmid DNA, CT-DNA, and AL-DNA (isolated from apricot leaf) were used for DNA studies. All the quaternized compounds exhibited acceptable DNA cleavage activities. Human topoisomerase I and E. coli topoisomerase enzymes were used for the topoisomerase I inhibition studies. All the quaternized complexes inhibited topoisomerase I activity. Moreover, these compounds were screened for cytotoxic and apoptotic effects against a human colon cancer cell line (DLD-1) by performing MTT and Annexin V assays. They exhibited toxicity and apoptotic effect on the DLD-1 cell line. The findings reveal that the compounds can be utilized for cancer therapy after further investigations.

New phthalonitrile/metal phthalocyanine-gold nanoparticle conjugates for biological applications.

The emergence of nanoscience and its effect on the development of diverse scientific fields, particularly materials chemistry, are well known today. In this study, a new di-substituted phthalonitrile derivative, namely 4,5-bis((4-(dimethylamino)phenyl)ethynyl)phthalonitrile (1), and its octa-substituted metal phthalocyanines {M = Co (2), Zn (3)} were prepared. All the newly synthesized compounds were characterized using a number of spectroscopic approaches, including FT-IR, mass, NMR, and UV-vis spectroscopy. The resultant compounds modified the surface of the gold nanoparticles (NG-1-3). Characterization of the newly synthesized conjugates was carried out by transmission electron microscopy. The antioxidant activity of compounds 1-3, NG-1-3, and NG was evaluated using the DPPH scavenging process and the highest radical scavenging activity was obtained with compounds 1, NG-1, 2, and NG-2 (100%). The antimicrobial activity of compounds 1-3, NG-1-3, and NG was studied using a microdilution assay and the most effective antimicrobial activity was obtained for NG-3 against all the tested microorganisms. The newly synthesized compounds demonstrated high DNA cleavage activity. Compounds 1-3, NG-1-3, and NG significantly inhibited the microbial cell viability of E. coli and exhibited perfect antimicrobial photodynamic therapeutic activity with 100% inhibition after 20 min LED irradiation. Besides, the biofilm inhibition activity of compounds 1-3, NG-1-3, and NG on the growth of S. aureus and P. aeruginosa were examined and compounds 1-3 and NG-1-3, especially NG-1-3, displayed high biofilm inhibition activities.

Investigation of the photoconductive properties of thiophene substituted metallo-phthalocyanines.

The synthesis of 4-(thiophen-3-ylethynyl)phthalonitrile was achieved via the Sonogashira cross-coupling reaction. Herein, we report the synthesis of symmetrical metallo-phthalocyanines with cobalt, zinc, and manganese as the metal ions, and tetrakis(ethynylthiophene) groups substituted at the peripheral positions. The new compounds have been characterized by using mass, 1H NMR, 13C NMR, FT-IR and UV-vis spectroscopy. Dark and photoconductivity measurements were carried out on spin coated thiophene substituted metallo-phthalocyanines at various temperatures fixed between 300 and 440 K. Photocurrent generation and charge transport mechanisms are discussed as well. The evaluation of the photoconductive properties of these compounds indicated that the photocurrent generation efficiency and charge transport mechanism exhibited a strong temperature dependence. On the other hand, conductivity measurements revealed that the temperature dependence of the conductivity can be described by the Arrhenius type exponential equation under dark conditions. Furthermore, it was found that the photoconductive behavior of the film can be described successfully by the variable range hopping model for the whole investigated temperature range.

Sensing alcohol vapours with novel unsymmetrically substituted metallophthalocyanines.

Unsymmetrically substituted phthalocyanines were synthesized by the well-known statistical condensation method using two differently substituted precursors, 4-tert-butylphthalonitrile and 4-(4-pyrrol-1-yl)phenoxyphthalonitrile. Spin-coated thin films of these compounds were subsequently exposed to varying concentrations of methanol, ethanol and butanol between 25 and 150 ppm in order to investigate the effects of the number of carbon atoms in the alcohol vapors. The results of this preliminary investigation indicated that sensor performance parameters such as sensitivity, response and recovery time strongly depend on the number of carbon atoms in the analyte molecules. It was found that the sensitivity of the sensors decreases with increasing number of carbon atoms. Electrochemistry studies of CoPc and MnClPc were carried out with cyclic and square wave voltammetry methods. Both complexes illustrated metal and ring-based electron transfer reactions. While CoPc underwent only one metal-based reduction ([CoIIPc2-]/[CoIPc2-]1-), two metal-based reductions ([Cl-MnIIIPc2-]/[Cl-MnIIPc2-]1- and [Cl-MnIIPc2-]1-/[Cl-MnIPc2-]2-) were observed with MnPc. Color changes during the in situ spectroelectrochemical measurements illustrated the versatility of the compounds for display technologies. Pyrrole-containing substituents of the complexes triggered their electropolymerization on the working electrode, which enhances their value as functional materials for modified electrodes.

Microwave-assisted synthesis of novel non-peripherally substituted metallophthalocyanines and their sensing behaviour for a broad range of Lewis bases.

The synthesis of novel, symmetrical, tetrasubstituted metallophthalocyanines (cobalt, zinc, and manganese) bearing four 2-(4-methyl-1,3-thiazol-5-yl)ethoxy units is reported. The new compounds have been characterized using UV-Vis, IR, (1)H NMR, (13)C NMR, and mass spectroscopy data. Photophysical properties of zinc(ii) phthalocyanines were found, including electronic absorption and fluorescence quantum yields. The fluorescence of the complexes was investigated in DMF and it was found that benzoquinone (BQ) was an effective quencher. The response and recovery behaviours of the spin coated films to different analytes, which span a broad range of Lewis bases, have been investigated by means of conductivity measurements. It was observed that the operating temperature had a considerable effect on the gas sensing performance of the sensors investigated. The sensing behaviour of the films for a broad range of Lewis bases and the correlation between the sensor sensitivity and Lewis base enthalpies were investigated. Results show that the sensitivity of the films may be correlated exponentially with the binding enthalpy.