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Development of robust and cost-effective smart materials requires rational chemical nanoengineering to provide viable technological solutions for a wide range of applications. Recently, a powerful approach based on the electrografting of diazonium salts has attracted a great deal of attention due to its numerous technological advantages. Several studies on graphene-based materials reveal that the covalent attachment of aryl groups via the above approach could lead to additional beneficial properties of this versatile material. Here, we developed the covalently linked metalorganic wires on two transparent, cheap, and conductive materials: fluorine-doped tin oxide (FTO) and FTO/single-layer graphene (FTO/SLG). The wires are terminated with nitrilotriacetic acid metal complexes, which are universal molecular anchors to immobilize His6-tagged proteins, such as biophotocatalysts and other types of redox-active proteins of great interest in biotechnology, optoelectronics, and artificial photosynthesis. We show for the first time that the covalent grafting of a diazonium salt precursor on two different electron-rich surfaces leads to the formation of the molecular wires that promote p-doping of SLG concomitantly with a significantly enhanced unidirectional cathodic photocurrent up to 1 ?A cm-2. Density functional theory modeling reveals that the exceptionally high photocurrent values are due to two distinct mechanisms of electron transfer originating from different orbitals/bands of the diazonium-derived wires depending on the nature of the chelating metal redox center. Importantly, the novel metalorganic interfaces reported here exhibit minimized back electron transfer, which is essential for the maximization of solar conversion efficiency. © 2022 American Chemical Society. All rights reserved.

This article addresses the fabrication of a novel and eco-friendly ceramic membrane based on basalt powder via press and sintering methods with a pore size of 1.5–2 μm. The basalt ceramic membrane (BCM) was grafted by SiO2 nanoparticles (50–60 nm) and ZnO nanorods (2.2 μm). The water permeability for the prepared membranes was measured 345.3, 701.4, and 801.9 L/m2 h bar for bare BCM, SiO2-BCM, and ZnO-BCM, respectively. The prepared membranes were used in Escherichia coli (E. coli) removal, and 100% E. coli removal efficiency was achieved at a transmembrane pressure of 0.5 bar for all membranes. The antimicrobial activities of the solid surfaces for BCM, SiO2-BCM, and ZnO-BCM were also studied using E. coli as a model test microorganisms. The antimicrobial activities for bare BCM, SiO2-BCM, and ZnO-BCM were 20.57%, 74.90%, and 100%, respectively. The results are of great importance in terms of the reusability of membranes and the prevention of biofilm formation in wastewater treatment processes.

Construction of green nanodevices characterised by excellent long-term performance remains high priority in biotechnology and medicine. Tight electronic coupling of proteins to electrodes is essential for efficient direct electron transfer (DET) across the bio-organic interface. Rational modulation of this coupling depends on in-depth understanding of the intricate properties of interfacial DET. Here, we dissect the molecular mechanism of DET in a hybrid nanodevice in which a model electroactive protein, cytochrome c(553) (cyt c(553)), naturally interacting with photosystem I, was interfaced with single layer graphene (SLG) via the conductive self-assembled monolayer (SAM) formed by pyrene-nitrilotriacetic acid (pyr-NTA) molecules chelated to transition metal redox centers. We demonstrate that efficient DET occurs between graphene and cyt c(553) whose kinetics and directionality depends on the metal incorporated into the bio-organic interface: Co enhances the cathodic current from SLG to haem, whereas Ni exerts the opposite effect. QM/MM simulations yield the mechanistic model of interfacial DET based on either tunnelling or hopping of electrons between graphene, pyr-NTA-M2+ SAM and cyt c(553) depending on the metal in SAM. Considerably different electronic configurations were identified for the interfacial metal redox centers: a closed-shell system for Ni and a radical system for the Co with altered occupancy of HOMO/LUMO levels. The feasibility of fine-tuning the electronic properties of the bio-molecular SAM upon incorporation of various metal centers paves the way for the rational design of the optimal molecular interface between abiotic and biotic components of the viable green hybrid devices, e.g. solar cells, optoelectronic nanosystems and solar-to-fuel assemblies.

In this study, RuO2-embedded PES membrane was prepared and it was used for protein separation. The antifouling properties of the fabricated composite membranes were also investigated using bovine serum albumin (BSA) as protein solution. The mean roughness increased proportionally by introducing RuO2 particles. The porosity of the composite membranes was higher than that of the pristine PES membrane. On the other hand, composite membranes has smaller average pore size after addition of RuO2 particles. The blending of RuO2 particles to the PES membrane caused to increase the hydrophilicity of the pristine membrane from 76.67° to 67.13°. The thermal studies of the PES/RuO2 membranes were performed by DTA/TG. The Activation Energy (Ea) values of the PES/RuO2 membranes were found to be 57.67-641.34 kJ/mol for Flynn-Wall-Ozawa (FWO) and 55.13–659.10 kJ/mol for Kissenger-Akahira-Sunose (KAS). The pure water flux of the composite membranes decreased from the pristine PES to PES/RuO2 1.00 wt%. The pore size was calculated as 14.5 nm and pore size decreased up to 6.5 nm when blended RuO2 particles increased up to 1.00 wt.%. BSA fluxes were 84.1 ± 2.1, 86.3 ± 2.5, and 93.9 ± 3.2 L/m2/h for pristine, PES/RuO2 0.50 wt%, and PES/RuO2 0.75 wt% membranes, respectively. PES/RuO2 1.00 wt%. membrane supplied the lowest BSA flux (73.6 ± 3.1 L/m2/h). BSA rejection efficiencies increased from 45.5 ± 1.8% to 92.6 ± 1.5% when blended RuO2 particles increased from 0 to 1.00 wt%. The results depicted that Rir values decreased while Rr values increased after the blending of RuO2.

Antibiotic resistance has been a growing problem for the public health. Especially the hospitalized patients are at high risk due to emergence of superbugs that can evade a wide range of antibiotics in use. In order to circumvent this major problem, new candidates of antimicrobial agents should be created and tested for their efficacies. Moreover, having antimicrobial agents that could get activated with light exposure (antimicrobial PDT) would create a great advantage in terms of decreasing the required effective dose as well as controlled localized activation of the candidate drugs. Schiff base derivatives have antimicrobial, antitumor, and anti-inflammatory activities. In this study, we used a unique set of Schiff base derivatives with and without copper for antimicrobial PDT applications both on gram-negative Escherichia coli and gram-positive Staphylococcus aureus. Our compounds had strong antimicrobial PDT potential especially with the addition of copper into their structures. Moreover, these Schiff base derivatives’ possible immunomodulatory activities were tested on mammalian macrophages in vitro. These compounds had photodynamic anti-inflammatory activities as well. Our results suggest that these unique Schiff bases can be utilized in antimicrobial PDT applications that can also alter the function of the immune system cells to suppress excessive inflammation.

We experimentally demonstrate that oriented assembly of red algal photosystem I (PSI) reaction centers on a plasmonically active Silver Island Film (SIF) leads to strong enhancement of both the fluorescence intensity and photocurrent generated upon illumination. PSI complexes were specifically attached to a monolayer of graphene deposited on the SIF layer. The results of comprehensive fluorescence microscopy point to the critical role of the SIF layer in enhancing the optical response of PSI, as we observe increased emission intensity. Hence, importantly, the strong increase of photocurrent generation demonstrated for the biohybrid electrodes can be directly associated with the plasmonic enhancement of the optical and electrochemical functionalities of PSI. The results also indicate that the graphene layer is not diminishing the influence of the plasmonic excitations in SIF on the absorption and emission of PSI. © The Royal Society of Chemistry 2020.

In this study, graphitic carbon nitride (g-C3N4)-based ZnO heterostructure was synthesized using a facile calcination method with urea and zinc nitrate hexahydrate as the initiators. According to the scanning electron microscopic (SEM) images, spherical ZnO particles can be seen along the g-C3N4 nanosheets. Additionally, the X-ray diffraction (XRD) analysis reveals the successful synthesis of the g-C3N4/ZnO. The photocatalytic activity of the synthesized catalyst was tested for the decolorization of crystal violet (CV) as an organic refractory contaminant. The impacts of ZnO molar ratio, catalyst amount, CV concentration, and H2O2 concentration on CV degradation efficiency were investigated. The obtained outcomes conveyed that the ZnO molar ratio in the g-C3N4 played a prominent role in the degradation efficiency, in which the degradation efficiency reached 95.9% in the presence of 0.05 mmol of ZnO and 0.10 g/L of the catalyst in 10 mg/L of CV through 120 min under UV irradiation. Bare g-C3N4 was also tested for dye decolorization, and a 76.4% dye removal efficiency was obtained. The g-C3N4/ZnO was also tested for adsorption, and a 32.3% adsorption efficiency was obtained. Photocatalysis, in comparison to adsorption, had a dominant role in the decolorization of CV. Lastly, the results depicted no significant decrement in the CV degradation efficiency in the presence of the g-C3N4/ZnO photocatalyst after five consecutive runs.

Here, we report the development of a novel photoactive biomolecular nanoarchitecture based on the genetically engineered extremophilic photosystem I (PSI) biophotocatalyst interfaced with a single layer graphene via pyrene-nitrilotriacetic acid self-assembled monolayer (SAM). For the oriented and stable immobilization of the PSI biophotocatalyst, an His6-tag was genetically engineered at the N-terminus of the stromal PsaD subunit of PSI, allowing for the preferential binding of this photoactive complex with its reducing side towards the graphene monolayer. This approach yielded a novel robust and ordered nanoarchitecture designed to generate an efficient direct electron transfer pathway between graphene, the metal redox center in the organic SAM and the photo-oxidized PSI biocatalyst. The nanosystem yielded an overall current output of 16.5 µA·cm−2 for the nickel- and 17.3 µA·cm−2 for the cobalt-based nanoassemblies, and was stable for at least 1 h of continuous standard illumination. The novel green nanosystem described in this work carries the high potential for future applications due to its robustness, highly ordered and simple architecture characterized by the high biophotocatalyst loading as well as simplicity of manufacturing.

Here, we report the development of a novel photoactive biomolecular nanoarchitecture based on the genetically engineered extremophilic photosystem I (PSI) biophotocatalyst interfaced with a single layer graphene via pyrene-nitrilotriacetic acid self-assembled monolayer (SAM). For the oriented and stable immobilization of the PSI biophotocatalyst, an His6-tag was genetically engineered at the N-terminus of the stromal PsaD subunit of PSI, allowing for the preferential binding of this photoactive complex with its reducing side towards the graphene monolayer. This approach yielded a novel robust and ordered nanoarchitecture designed to generate an efficient direct electron transfer pathway between graphene, the metal redox center in the organic SAM and the photo-oxidized PSI biocatalyst. The nanosystem yielded an overall current output of 16.5 µA·cm−2 for the nickel- and 17.3 µA·cm−2 for the cobalt-based nanoassemblies, and was stable for at least 1 h of continuous standard illumination. The novel green nanosystem described in this work carries the high potential for future applications due to its robustness, highly ordered and simple architecture characterized by the high biophotocatalyst loading as well as simplicity of manufacturing.

Photodynamic therapy (PDT) is a noninvasive therapy based on the photodynamic effect. in this study, we sought to determine intracellular uptake and in vivo photodynamic therapy potential of Zn phthalocyanine-loaded mesoporous silica nanoparticles (MSNPS) against pancreatic cancer cells. MSNPS were labeled with I-131; the radiolabeling efficiency was found to 95.5 +/- 1.2% in pH 9 and 60 min reaction time. Besides, the highest intracellular uptake yields of I-131-MSNPS nanoparticles in MIA PaCa-2, AsPC-1, and PANC-1 cells were determined as 43.9 +/- 3.8%, 41.8 +/- 0.2%, and 37.9 +/- 1.3%, respectively, at 24 h incubation time. in vivo PDT studies were performed with subcutaneous xenograft cancer model nude mice with AsPC-1 pancreatic cancer cells. For photodynamic therapy, 685 nm red laser light 100 J/cm(2) light dose using and 5-20 mu M ZnPc containing MSNPS concentrations were applied. Histopathological studies revealed that the ratio of necrosis in tumor tissue was higher in the treatment group than the control groups., Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [2214/A]; Ege University, Scientific Research Project (BAP)Ege University [16 NBE 001], This research was funded by the Scientific and Technological Research Council of Turkey (TUBITAK; grant number2214/A), Ege University, Scientific Research Project (BAP; grant Number: 16 NBE 001).

In this study, Subphthalocyanine (SubPc) and SubPc integrated TiO2 nanoparticles (SubPc- TiO2) were examined as theranostic agents. In vitro photodynamic therapy (PDT) efficiency of SubPc/SubPc-TiO2 and nuclear imaging potential of 131I labeled SubPc/TiO2-SubPc were determined on hepatocellular carcinoma (HepG2), colorectal adenocarcinoma (HT29) and human healthy lung (WI38) cell lines. As a result, 131I-SubPc and 131I-SubPc-TiO2 have been identified as a nuclear imaging agent for liver cancer. Additionally, 131I-SubPc-TiO2 has been found to be promising for imaging colon tumors. According to the in vitro photodynamic therapy studies, SubPc and SubPc-TiO2 were determined suitable PDT agents for liver and colon tumors. These results suggest that SubPc-TiO2 might be a theranostic agent with both PDT and nuclear imaging potential.

In recent years, photocatalysis upon semiconductor-based hybrid materials has received much attention for the improved environmental effects and energy applications. Many good semiconductors such as ZnO have large bandgaps and suffer from fast charge recombination which hinders photocatalytic activity. One possible strategy to overcome this problem is introducing a narrow bandgap co-catalyst. Within the context of this study, triple hybrid nanostructures comprised of ZnO nanorods and MoS2/rGO (MG) co-catalyst were synthesized and characterized by various analytical methods. Accordingly, 25ZnO/75MG and 75ZnO/25MG hybrid materials were synthesized for two different MG co-catalyst comprised of 0.5% (named as 25ZnO/75MG1) and 5% (named as 25ZnO/75MG2) graphene oxide. The photocatalytic activities of the heterostructures and pristine ZnO nanorods were evaluated by the degradation of BR 18 dye, a common water pollutant mainly from the textile industry. When introduced with the co-catalyst, 25ZnO/75MG1 heterostructures achieved 100% degradation for 180 min. Furthermore, when the GO amount in the co-catalyst was increased to 5%, fully degradation of the dye solution was realized by 25ZnO/75MG2 in the first 30 min. These results are indicative of a positive synergistic effect of MoS2-rGO co-catalyst. Also, it is shown that increasing the GO amount is an effective approach to accelerate charge separation and electron transport properties.

This study aims to investigate the modification of polyethersulfone (PES) membrane with boron nitride quantum dots (BNQD) for improving the antifouling performance. The composite membranes were synthesized by blending different amounts of BNQD (0.50, 1.00, and 2.00 wt.%) into PES with the non-solvent induced phase separation (NIPS) method. UV–vis absorption, X-ray diffraction (XRD), and transmission electron microscopy (TEM) were used to characterize BNQD. Moreover, porosity, pore size, contact angle, permeability, bovine serum albumin (BSA) rejection, and antifouling properties were determined for composite membranes. The enhanced biological activity of BNQD was investigated based on antioxidant, antimicrobial, anti-biofilm, bacterial viability inhibition, and DNA cleavage studies. The BNQD showed 19.35 % DPPH radical scavenging activity and 76.45 % ferrous ion chelating activity at 500 mg/L. They also exhibited good chemical nuclease activity at all concentrations. BNQD had moderate antibacterial activity against all tested microorganisms. Biofilm inhibition percentage of BNQD was determined as 82.31 % at 500 mg/L. Cell viability assay demonstrated that the BNQD showed strong cell viability inhibition 99.9 % at the concentration of 1000 mg/L. The porosity increased from 56.83 ± 1.17%–61.83 ± 1.17 % while BNQD concentration increased from 0 to 2.00 wt%. Moreover, the hydrophilicity of BNQD nanocomposite membranes also increased from 75.42 ± 0.56° to 65.34 ± 0.25°. The mean pore radius is far slightly changed from 16.47 ± 0.35 nm to 19.16 ± 0.22 nm. The water flux increased from 133.5 ± 9.5 L/m2/h (for pristine membrane) to 388.6 ± 18.8 L/m2/h (for PES/BNQD 2.00 wt% membrane). BSA flux increased from 38.8 ± 0.9 L/m2/h to 63.2 ± 2.7 L/m2/h up to 1.00 wt% amount of BNQD nanoparticles.

This study aims to investigate the modification of polyethersulphone (PES) membrane with graphitic carbon nitride (g-C3N4) nanosheets for improving the antifouling and separation performance. The nanocomposite membranes were fabricated with blending of different g-C3N4 nanosheets (0.50, 1.00, and 2.00 wt%) into PES and they were synthesized by the phase inversion method. The fabricated g-C3N4 nanosheets and composite membranes were analyzed for their morphology. Scanning electron microscopy (SEM) with Energy Dispersive X-Ray Analysis (EDX) mapping were used to detect the distribution of g-C3N4 nanosheets on membrane surface, whereas surface roughness of membrane was evaluated by atomic force microscopy (AFM). The composite membrane surface was found to be hydrophilic (67.54°), while the water flux of the composite membrane was found to be 254.8 L/m2/h for 2.00 wt% g-C3N4/PES membrane. The bovine serum albumin (BSA) separation tests indicated that the composite membrane supplied 98.5% BSA rejection ratio. Moreover, a significant improvement in antifouling characteristics were verified from BSA filtration experiments. g-C3N4 was also investigated for some of its biological properties such as antioxidant, antimicrobial, DNA cleavage, biofilm inhibition, and bacterial viability effect. g-C3N4 showed good free radical scavenging activity and moderate chelating activity at 500 mg/L. It was also determined that single-strand DNA cleavage activities occurred at all tested concentrations. g-C3N4 exhibited significant antibiofilm activity and inhibitory effects on E. coli vitality as 90.9%, 97.1%, and 98.9% at 250, 500, and 1000 mg/L, respectively. This study provides a simple and useful guideline to create a UF membrane resistant against organic fouling and expand its practical applications for wastewater treatment.

The highly efficient bioelectrodes based on single layer graphene (SLG) functionalized with pyrene self-assembled monolayer and novel cytochrome c553 (cyt c553) peptide linker variants were rationally designed to optimize the direct electron transfer (DET) between SLG and the heme group of cyt. Through a combination of photoelectrochemical and quantum mechanical (QM/MM) approaches we show that the specific amino acid sequence of a short peptide genetically inserted between the cyt c553 holoprotein and the surface anchoring C-terminal His6-tag plays a crucial role in ensuring the optimal orientation and distance of the heme group with respect to the SLG surface. Consequently, efficient DET occurring between graphene and cyt c553 leads to a 20-fold enhancement of the cathodic photocurrent output compared to the previously reported devices of a similar type. The QM/MM modeling implies that a perpendicular or parallel orientation of the heme group with respect to the SLG surface is detrimental to DET, whereas the tilted orientation favors the cathodic photocurrent generation. Our work confirms the possibility of fine-tuning the electronic communication within complex bio-organic nanoarchitectures and interfaces due to optimization of the tilt angle of the heme group, its distance from the SLG surface and optimal HOMO/LUMO levels of the interacting redox centers.

A series of non-aggregated zinc phthalocyanine derivatives containing either bulky thiophenol or phenol substituents were synthesized as a novel donor component for bulk heterojunction (BHJ) solar cell applications. The molecular structure and photophysical properties of ZnPc derivatives were investigated by combined experimental and theoretical studies using density functional theory (DFT) and time-dependent DFT (TD-DFT) methods. In order to evaluate the physical properties of ZnPcs in the solvent environment, we applied the conductor-like polarizable continuum model (CPCM). Within this scope, light-harvesting efficiency (LHE), excited-state lifetime (τ), maximum absorption wavelengths (λmax), oscillator strength (f) and hyperpolarizability (β tensors) were calculated both in vacuum and chloroform (e = 4.9) medium. Furthermore, divergent types of global descriptors such as EHOMO, ELUMO, and bandgap (Egap) energies, ionization potential (I), electron affinity (A), hardness (η), and electrophilicity index (ω) were also calculated. Our computational findings revealed that the linker heteroatoms [sulfur for the ZnPc (1–2); oxygen for the ZnPc (3–4) including the substituent type (isopropyl for the ZnPc (2–4), and phenyl for the ZnPc (1–3] severely affected the photophysical properties of the dyes. In relation, theoretical results are in good accordance with our experimental observations. Finally, ZnPc derivatives were used as a donor component and PC61BM as an acceptor material in BHJ solar cells, displaying a maximum power conversion efficiency of 0.8%. Compared with ZnPcs 1–2, ZnPc 3–4 based cells showed an inferior photovoltaic performance. These results are promising and should encourage further studies on BHJ solar cells using near-infrared absorbing and non-aggregated ZnPcs.

Zinc chlorin derivatives consisting of primary, secondary and tertiary amine unit were prepared and their aggregation properties have been studied both in solution and in solid state in order to investigate the influence of the amine moiety on the formation of self-assembled nanostructures. The supramolecular organization ability of these derivatives have been investigated on the solid substrate, namely, highly oriented pyrolytic graphite (HOPG) by using AFM (atomic force microscopy) and STM (scanning tunneling microscopy) spectroscopy. The supramolecular organization of zinc chlorin derivatives in solution has been further supported by UV-vis spectroscopy. Zinc chlorins bearing primary, secondary amine exhibit well-ordered J-type aggregation in solution and well-defined self-organization on HOPG. On the other hand, the self-organization of tertiary amine substituted zinc chlorin both in solution and in solid state was less pronounced. (C) 2017 Elsevier B.V. All rights reserved.

WOS: 000460467300022, Antibiotic resistance is an increasing healthcare problem worldwide. In the present study, the effects of antimicrobial photodynamic therapy (APDT) of ZnPc and ZnPc-integrated TiO2 nanoparticles (ZnPc-TiO2) were investigated against Staphylococcus aureus. A light emitting diode (LED) (630-700 nm, 17.4 mW/cm(2)) was used on S. aureus at different light doses (8 J/cm(2) for 11 min, 16 J/cm(2) for 22 min, 24 J/cm(2) for 33 min) in the presence of the compounds under the minimum inhibitory concentration values. Both compounds showed similar phototoxicity toward S. aureus when high light doses (16 and 24 J/cm(2)) were applied. In addition, the success of APDT increased with an increasing light dose., Ege University, Scientific Research Project (BAP)Ege University [18NBE003], This research was supported by the Ege University, Scientific Research Project (BAP), Project Number: 18NBE003.

EgeUn###, This study, subphthalocyanines (SubPc) and SubPc integrated TiO2 nanoparticles (SubPc-TiO2) were synthesized as novel photosensitizers. Their PDT effects were evaluated. Furthermore, nuclear imaging potential of 131I-labelled SubPc/SubPc-TiO2 were examined in mouse mammary carcinoma (EMT6) and cervix adenocarcinoma (HeLa) cell lines. The uptake results show that SubPc labelled with 131I radionuclide (131I-SubPc) in EMT6 and HeLa cell lines was found to be approximately the same as in the WI38 cell line. However, the uptake values of SubPc-TiO2 labelled with 131I (131I-SubPc-TiO2) in EMT6 and HeLa cell lines were determined to be two times higher than in the WI38 cell line. In other words, the target/non-target tissue ratio was identified as two in the EMT6 and HeLa cell lines. 131I-SubPc-TiO2 is promising for imaging or treatment of breast and cervix tumors. In vitro photodynamic therapy studies have shown that SubPc and SubPc-TiO2 are suitable agents for PDT. In addition, SubPc-TiO2 has higher phototoxicity than SubPc. As a future study, in vivo experiments will be held and performed in tumor-bearing nude mice. © 2019 World Scientific Publishing Company., Mersin Üniversitesi Ege Üniversitesi TR33400 114Z430, aDepartment of Nuclear Applications, Institute of Nuclear Science, Ege University, Bornova, 35100, Izmir, Turkey bDepartment of Energy Systems Engineering, Faculty of Technology, Tarsus University, TR33400, Tarsus, Turkey cDepartment of Biomedical Technology, Institute of Science, Ege University, Bornova, 35100, Izmir, Turkey dDepartment of Medical Biology, Faculty of Medicine, Ege University, Bornova, 35100, Izmir, Turkey eAdvanced Technology Research & Application Center, Mersin University, Ciftlikkoy Campus, TR33343, Yenisehir, Mersin, Turkey -- The authors gratefully acknowledge financial support by The Scientific and Technological Research Council of Turkey, TUBITAK (Grant no: 114Z430).

A major bottleneck in the fabrication of efficient bio-organic nanoelectronic devices resides in the strong charge recombination that is present at the different interfaces forming the complex system. An efficient way to overcome this bottleneck is to add a self-assembled monolayer (SAM) of molecules between the biological material and the electrode that promotes an efficient direct electron transfer whilst minimising wasteful processes of charge recombination. In this work, the presence of a pyrene-nitrilotriacetic acid layer carrying different metal centers as SAM physisorbed on graphene is fully described by mean of electrochemical analysis, field emission scanning electron microscopy, photoelectrochemical characterisation and theoretical calculations. Our multidisciplinary study reveals that the metal center holds the key role for the efficient electron transfer at the interface. While Ni2+ is responsible for an electron transfer from SAM to graphene, Co2+ and Cu2+ force an opposite transfer, from graphene to SAM. Moreover, since Cu2+ inhibits the electron transfer due to a strong charge recombination, Co2+ seems the transition metal of choice for the efficient electron transfer., Comment: 28 pages, 7 figures

In this study, a novel polyethersulphone (PES) composite membrane incorporated with two different zinc phthalocyanines (ZnPc), tetra-iodo and octa(2,6-diphenylphenoxy), was fabricated through the phase inversion approach. Three different concentrations of zinc phthalocyanines (0.5, 1.0, and 2.0 wt.%) were blended into the PES membrane. The morphology and performance of the fabricated composite membranes were systematically studied by scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS) mapping, atomic force microscopy (AFM), porosity, water contact angle, antifouling, and rejection measurements. Hydrophobicity of the pristine membrane decreased from 79.67° to 77.03° and from 79.67° to 67.57° after blending of 2.0 wt.% tetra-iodo ZnPc (TI-ZnPc) and octa(2,6-diphenylphenoxy) ZnPc (DP-ZnPc), respectively. Furthermore, the porosity and mean pore radius decreased due to the introducing of ZnPc. Porosity of the pristine membrane decreased from 60.60 % to 44.96 % and 42.21 % after blending of TI-ZnPc and DP-ZnPc, respectively. Mean pore size of the pristine membrane decreased from 22.70 nm to 9.11 nm and 17.93 nm after blending of TI-ZnPc and DP-ZnPc, respectively. BSA filtration mostly affected the flux of pristine membrane and caused it to decrease from 133.5 to 87.1 L/m2h (relative flux reduction (RFR) of 34.7 %). RFR decreased up to 19.2 % and 17.3 % for TI-ZnPc 2.0 wt% and DP-ZnPc 2.0 wt% composite membranes. Pristine PES membrane rejected 45.8 % BSA. However, TI-ZnPc 2.0 wt% and DP-ZnPc 2.0 wt% composite membranes supplied 91.0 % and 70.6 % BSA rejections, respectively. In comparison to pristine PES membrane, the total resistance (Rt) values of the composite membranes decreased. The pristine PES membrane showed the lowest flux recovery ratio (FRR, 71.89 %) against BSA, while all-composite membranes showed promising antifouling properties. FRR increased up to 97.44 % and 89.06 % for TI-ZnPc 2.0 wt% and DP-ZnPc 2.0 wt% composite membranes, respectively. The pristine PES membrane showed the lowest FRR against activated sludge, while all composite membranes showed promising antifouling properties. Moreover, ZnPc-embedded PES composite membranes were irradiated with appropriate wavelengths of light in the presence of oxygen to generate reactive oxygen species to clean fouled membranes’ surface. The results showed that photo-cleaning was very effective to recover membrane flux.

In this study, a novel polyethersulphone (PES) nanocomposite membrane incorporated with copper zinc tin sulfide (Cu2ZnSnS4) nanoparticles (CZTS NPs) was prepared through the phase inversion method. First, the samples containing different copper and zinc ratios in CZTS stoichiometry were prepared and characterized. The effect of copper and zinc ratio changes were examined on the photocatalytic properties of both NPs and nanocomposite membranes. The photocatalytic effect was tested and BR18 dye was degraded at 88.0% efficiency when exposed to visible light for 180 min in the presence of CZTS1.0 NPs catalyst. The results also exhibited that CZTS NPs blended membrane showed good self-cleaning performance. Second, we investigated the antioxidant, DNA cleavage, and biofilm inhibition activities of CZTS NPs. The antimicrobial activities of CZTS NPs were tested against seven microbial strains. The highest 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging and chelating activities were found as 81.80 ± 1.75% and 72.19 ± 4.63%, respectively. CZTS NPs exhibited double-strand DNA cleavage activity at 500 mg/L. They showed significant biofilm inhibition as 92.15 ± 5.67% against Staphylococcus aureus. CZTS NPs displayed moderate antimicrobial effects against tested microorganisms. Third, CZTS NPs were blended in polyethersulphone (PES) membrane and the morphology as well as performance of the fabricated nanocomposite membranes were systematically investigated by SEM-EDX, porosity, water contact angle, antifouling, and rejection measurements. The water flux of resulting nanocomposite membranes was markedly enhanced due to the introducing of CZTS NPs. Meanwhile, the nanocomposite membranes demonstrated remarkable antifouling properties (flux recovery ratio ∼94%) in contrast with the bare PES (flux recovery ratio ∼51%) when BSA was filtrated. The high retention of BSA (100%) as well as high permeation flux (73.8 ± 9.8 L/m2/h) of the CZTS2.00 wt% membrane demonstrated that the constructed nanocomposite membrane possessed the characteristics of a promising membrane for purification of proteins.

This study was performed to synthesize membranes of polyethersulfone (PES) blended with graphene oxide (GO) and PES blended with GO functionalized with photoactive semiconductor catalyst (TiO2 and ZnO). The antifouling and self-cleaning properties of composite membranes were also investigated. The GO was prepared from natural graphite powder by oxidation method at low temperature. TiO2 and ZnO nanopowders were synthesized by anhydrous sol–gel method. The surface of TiO2 and ZnO nanopowders was modified by a surfactant (myristic acid) to obtain a homogeneously dispersed mixture in a solvent, and then GO was functionalized by loading with these metal oxide nanopowders. The PES membranes blended with GO and functionalized GO into the casting solution were prepared via phase inversion method and tested for their antifouling as well as self-cleaning properties. The composite membranes were synthesized as 14%wt. of PES polymer with three different concentrations (0.5, 1.0, and 2.0%wt.) of GO, GO-TiO2, and GO-ZnO. The functionalization of membranes improved hydrophilicity property of membranes as compared to neat PES membrane. However, the lowest flux was obtained by functionalized membranes with GO-TiO2. The results showed that functionalized membranes demonstrated better self-cleaning property than neat PES membrane. Moreover, the flux recovery rate of functionalized membranes over five cycles was higher than that of neat membrane.

The stability of the optical parameters of a ruthenium polypyridyl complex (Ru-PC K314) film under varying annealing temperatures between 278 K and 673 K was investigated. The ruthenium polypyridyl complex thin film was prepared on a quartz substrate by drop casting technique. The transmission of the film was recorded by using Ultraviolet/Visible/Near Infrared spectrophotometer and the optical band gap energy of the as-deposited film was determined around 2.20 eV. The optical parameters such as refractive index, extinction coefficient, and dielectric constant of the film were determined and the annealing effect on these parameters was investigated. The results show that Ru PC K314 film is quite stable up to 595 K, and the rate of the optical band gap energy change was found to be 5.23 × 10- 5 eV/K. Furthermore, the thermal analysis studies were carried out in the range 298-673 K. The Differential Thermal Analysis/Thermal Gravimmetry/Differantial Thermal Gravimmetry curves show that the decomposition is incomplete in the temperature range 298-673 K. Ru-PC K314 is thermally stable up to 387 K. The decomposition starts at 387 K with elimination of functional groups such as CO2, CO molecules and SO3H group was eliminated between 614 K and 666 K., State Planning Organization of Turkey (DPT2003K120390); Scientific and Technological Research Council of Turkey (TBAG-109T240)

Photodynamic therapy (PDT) is a medical treatment for the removal of target tissues involving the delivery of a photosensitizer agent followed by irradiation with visible light. In the present study, symmetric Zn(II) Pc 1 and asymmetrically substituted Zn(II) Pc 2 were synthesized and examined multifunctional agents for tumor nuclear imaging and PDT potential. The Zn(II) Pc 1 and Zn(II) Pc 2 were radiolabeled with 131 I with high efficiency (93.4 ± 1.6% and 91.4 ± 1.6%, respectively). The results of the biodistribution study showed that radiolabeled Zn(II) Pc 1 had high uptake on lung, large intestine, ovary and pancreas. However, the uptake of radiolabeled Zn(II) Pc 2 was statically significant in pancreas and intestine. In PDT studies, EMT6/P (mouse mammary cell) and HeLa (cervical adenocarcinoma cell) with Zn(II) Pc 1 and Zn(II) Pc 2 were exposed to red light at the doses of 10–30 J/cm 2 . Although PDT activity of Zn(II) Pc 2 in HeLa cell line was determined, Zn(II) Pc 1 showed no phototoxic effect in both cell lines. In conclusion, radiolabeled Zn(II) Pc 1 might be a promising imaging agent for the lung, the ovary pancreas, and the colon tumors. However, radiolabeled Zn(II) Pc 2 might be a promising nuclear imaging agent for the colon and the pancreas tumors and promising PDT agent for cervical tumors.

ZnO nanopowder was synthesized via a hydrothermal route and characterized with several methods such as XRD, TG/DTA, FT-IR, FE-SEM, TEM and Electron Paramagnetic Resonance spectroscopy (EPR) in order to investigate the effect of growing time and Mn doping on the defects which occurred. The pure ZnO nanopowder was obtained in a hexagonal phase with (101) as the preferred orientation except for the one prepared for 36 h which is (002). The growing time does effect the orientation of the crystallite whereas the Mn-doping does not. The concentration of Mn2+ significantly increases the spin–spin interaction in the ZnO : Mn nanopowder. It was observed that there was a competition between intrinsic (Zn and O vacancies) and extrinsic (Mn2+ ion) structural defects but still the former defects are dominant in ZnO : Mn. The effect of growing time and concentration of Mn2+ on the activation energy of ZnO and the ZnO : Mn nanopowder are calculated by Kissinger–Akahira–Sunose (KAS) and Flynn–Wall–Ozawa (FWO) methods.

WOS: 000500166500141, The effects of Fe2O3 based DOCs (Diesel Oxidation Catalyst) and SCR (Selective Catalytic Reduction) catalysts on the exhaust emissions of diesel engine were investigated in this experimental study. The investigated catalysts, Al2O3 - TiO2/CeO2/Fe2O3 (ATCF) and Al2O3- Nb2O5/CeO2/Fe2O3 (ANCF), were produced with impregnation method and aged for 6 h at 600 degrees C. FE-SEM (Field Emission Scanning Electron Microscopy), XRD (X-Ray Diffraction), XRF (X-Ray Fluorescence) and BET (Brunauer-Emmett-Teller) Surface Area analyzes were carried out to determine the specifications of catalysts. The catalytic performances of the DOCs were tested for the oxidation of CO, HC, PM, NO while SCR catalysts were tested for SCR of NOx using NH3. An individual exhaust system was built up and mounted to the engine for tests of catalysts. An electronic control system and a software were developed to control the SCR system. After the completion of experimental setup, catalysts placed inside the exhaust system were subjected to the engine tests to determine their effects on the exhaust emissions. Tests were carried out under actual working conditions with a single cylinder direct injection diesel engine. In conclusion, the catalysts made significant decrease in pollutant emissions while brake specific fuel consumption (BSFC) increased slightly. ANCF released better conversion efficiency in all pollutant emissions compared to the ATCF. Maximum decreases in CO, HC and NOx emissions, which are resulted from ANCF catalyst, were obtained at a rate of 83.51%, 80.83% and 80.29% respectively.

The fabrication of highly efficient bio-organic nanoelectronic devices is still a challenge due to the difficulty in interfacing the biomolecular component to the organic counterparts. One of the ways to overcome this bottleneck is to add a self-assembled monolayer (SAM) in between the electrode and the biological material. The addition of a pyrene–nitrilotriacetic acid layer to a graphene metal electrode enhances the charge transfer within the device. Our theoretical calculations and electrochemical results show that the formation of a pyrene–nitrilotriacetic acid SAM enforces a direct electron transfer from graphene to the SAM, while the addition of the Ni2+ cation and imidazole reverses the charge transfer direction, allowing an atomic control of the electron flow, which is essential for a true working device.

It has become inevitable to design non-enzymatic biosensors to eliminate the drawbacks of enzymatic biosensors prepared using enzymes which are expensive and without long-term stability. For this purpose, a single layer graphene film was prepared by chemical vapor deposition method on Cu foil and transferred to the FTO glass slide. After that copper nanoparticles (CuNP) were decorated by the inert-gas condensation method based on DC magnetron sputtering on it. The prepared CuNP decorated graphene film was characterized and used as a non-enzymatic sensor platform for the detection of glucose. The sensor platform exhibited a fast response time of less than 4 s and the sensitivity of 430.52 μA mM−1 cm-2 with linear concentration range (0.01–1.0 mM) having detection limit 7.2 μM. Electrochemical investigations indicate that the sensor platform which is decorated CuNP graphene film possess an excellent performance toward glucose. Prepared biosensors platform could be used and applied in the field of new drug discovery, biomedical, clinical diagnosis and forensic science to miniaturize of detection instrument and reduce detection sample and period. © 2018 Elsevier B.V.

In this study, the biological potential of a nickel chlorophyll derivative (Ni-PH-A) as a multimodal agent for tumor imaging and photodynamic therapy (PDT) was investigated. Optimum conditions of labeling with I-131 were investigated and determined as pH 10 and 1 mg amount of iodogen. Biodistribution results of I-131 labeled Ni-PH-A in female rats indicated that radiolabeled Ni-PH-A maximum uptake in the liver, spleen and ovary was observed at 30 min. Intercellular uptake and PDT efficacy of Ni-PH-A were better in MDAH-2774 (human ovarian endometrioid adenocarcinoma) than in MCF-7 (human breast adenocarcinoma) cells. Ni-PH-A might be a promising multimodal agent for lung, ovary and liver tumor imaging and PDT.

In this paper, we report the synthesis and characterization of a new cyclometallated iridium complex, [tetrakis(2,2'-bipyridine-4,4'-dicarboxylic acid)(p-dichloro)diiridium (III)] chloride complex, [(dcbpy)(2)lr(mu-CI)](2)Cl-4. Four different ionic liquids are also synthesized and characterized for electrolyte combinations. Photovoltaic performance of dye sensitized solar cells have been studied by using four different ionic liquids. The dye sensitized nanocrystalline TiO2 solar cell (DSSC) based on the iridium complex using triethyleneglycol-bis(3-methylimidazolium)diiodide [K36-TFSI] as ionic liquid in electrolyte showed the best photovoltaic performance with a maximum short-circuit photo-current density (f(sc)) of 4.45 mA cm(-2), an open circuit photovoltage (V-oc) of 550 mV, and a Fill factor (FF) of 0.60, corresponding to an overall conversion efficiency of 1.47% under AM 1.5 sun light. (C) 2014 Elsevier Ltd. All rights reserved

Two ruthenium complexes with carboxyl and sulfonyl groups have been synthesized, [Ru-II(L1)(2)(NCS)(2)] Ru(II)bis(4,7-diphenyl-1,10-phenanthroline-disulfonic acid disodium salt)-di(thiocyanate) 110131, [Ru-II(L1)(2)(dcbpy)] Ru-II bis(4,7-dipheny1-1,10-phenanthroline-disulfonic acid disodium salt)(4,4'dicarboxy-2,2'-bipyridyl) [1014] as photosensitizers. UV vis, fluorescence emissjon, AFM and CV measurements are also supplied for ruthenium complexes. Photovoltaic properties of dye sensitized nanocrystalline semiconductor solar cells based on Ruthenium complexes which bear carboxyl and sunfonyl groups have been tested under standard AM 1.5 sunlight. Under the standard global AM 1.5 solar conditions, 1(314 and 1(K313-sensitized solar cells demonstrate short circuit photocurrent densities of 14.92 mA/cm(2) and 11.23 mA/cm(2) and overall conversion efficiencies of 5.09% and 4.02%, respectively. (C) 2013 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.

The electronic coupling between a robust red algal photosystem I (PSI) associated with its light harvesting antenna (LHCI) and nanocrystalline n-​type semiconductors, TiO2 and hematite (α-​Fe2O3) is utilized for fabrication of the biohybrid dye-​sensitized solar cells (DSSC)​. PSI-​LHCI is immobilized as a structured multilayer over both semiconductors organized as highly ordered nanocrystalline arrays, as evidenced by FE-​SEM and XRD spectroscopy. Of all the biohybrid DSSCs examined, α-​Fe2O3/PSI-​LHCI biophotoanode operates at a highest quantum efficiency and generates the largest open circuit photo-​current compared to the tandem system based on TiO2/PSI-​LHCI material. This is accomplished by immobilization of the PSI-​LHCI complex with its reducing side towards the hematite surface and nanostructuring of the PSI-​LHCI multilayer in which the subsequent layers of this complex are organized in the head-​to-​tail orientation. The biohybrid PSI-​LHCI-​DSSC is capable of sustained photoelectrochemical H2 production upon illumination with visible light above 590 nm. Although the solar conversion efficiency of the PSI-​LHCI​/hematite DSSC is currently below a practical use, the system provides a blueprint for a genuinely green solar cell that can be used for molecular hydrogen production at a rate of 744 μmoles H2 mg Chl-​1 h-​1, placing it amongst the best performing biohybrid solar-​to-​fuel nanodevices.

Ocakoglu, Kasim/0000-0003-2807-0425; colak, suleyman gokhan/0000-0002-4978-1499; Tuncel, Ayca/0000-0003-0699-3309, WOS: 000494641300170, PubMed: 31667420, A series of imidazolium bromide salts (NIM-Br 1a, 1b and 1c) bearing different lengths of alkyl chains were synthesized and theirin vitro antibacterial activities were determined by measuring the minimum inhibitory concentration (MIC) values for Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Enterococcus faecalis. in addition, these imidazolium derivatives were also evaluated against biofilm produced by these bacterial strains. All compounds were found to be effective against Gram-positive and Gram-negative bacteria, and also more effective on the S. aureus biofilm production than the others., Ege University, Scientific Research Project (BAP)Ege University [16FBE008], This work was supported by the Ege University, Scientific Research Project (BAP), and Project Number: 16FBE008.

A new method for synthesis of titanium dioxide (TiO2)-dye nanoparticles is reported. TiO2 nanocrystals were obtained at 150 and 200 degrees C by using chemically bonded TiO2-sensitizer dye as a precursor. Titanium tetraisopropoxide was first modified with a dye molecule and then precipitated by dropping into acidic water. A strongly colored precipitate was obtained. Hydrothermal growth of a colloidal solution was carried out in a Teflon-lined stainless steel autoclave. Dye sensitized solar cell efficiencies obtained were comparable and fill factor values were close to the analogous cells prepared by the use of conventional TiO2 paste techniques. This method allows the use of different substrates together with nanocrystalline TiO2 for many technological applications. (C) 2013 Elsevier Ltd. All rights reserved.

The development of new energy materials that can be utilized to make renewable and clean fuels from abundant and easily accessible resources is among the most challenging and demanding tasks in science today. Solar-powered catalytic water-splitting processes can be exploited as a source of electrons and protons to make clean renewable fuels, such as hydrogen, and in the sequestration of CO2 and its conversion into low-carbon energy carriers. Recently, there have been tremendous efforts to build up a stand-alone solar-to-fuel conversion device, the "artificial leaf", using light and water as raw materials. An overview of the recent progress in electrochemical and photo-electrocatalytic water splitting devices is presented, using both molecular water oxidation complexes (WOCs) and nano-structured assemblies to develop an artificial photosynthetic system.

The change in the crystal and electronic structure properties of wurtzite ZnO nanoparticles was studied according to Mn doping in the powder samples. The investigations were conducted by X-ray Absorption Fine Structure Spectroscopy (XAFS) technique for the samples prepared with different heating and doping processes. Electronic analysis was carried out by the collected data from the X-ray Absorption Near-Edge Structure Spectroscopy (XANES) measurements. Additional crystal structure properties were studied by Extended-XAFS (EXAFS) analysis. Longer heating periods for the undoped wurtzite ZnO samples were determined to own stable crystal geometries. However, for some doped samples, the distortions in the crystal were observed as a result of the low doping amounts of Mn which was treated as an impurity. Besides, the changes in oxygen locations were determined to create defects and distortions in the samples. (C) 2016 Chinese Materials Research Society. Production and hosting by Elsevier B.V.

Novel artificial zinc chlorin dyes comprising amine anchoring groups zinc aminochlorin (ZnChl-NH2), zinc monomethylaminochlorin (ZnChl-NHMe) and zinc dimethylaminochlorin (ZnChl-NMe2) are synthesized and their photovoltaic performances are evaluated in dye-sensitized solar cells. To the best of our knowledge, -NH2 functionalized Zn chlorin dyes are tested in dye-sensitized solar cells for the first time. Best efficiency is obtained with ZnChl-NHMe sensitizer with a 2.67 mA/cm(2) short circuit photocurrent density, 414 mV of open circuit voltage, 0.64 of filling factor, and 0.68 of overall light to power conversion efficiency. (C) 2015 Elsevier B.V. All rights reserved.

In this paper we proposed a new approach to modify the Langmuir model by considering nonlinear effects such as diffusion of water molecules in/out of an adsorbing film for humidity adsorption and desorption kinetics. The model was tested on the humidity adsorption and desorption data of a spin coated 50. nm thick Ruthenium polypridyl complex (Ru-PC K314) film, measured under relative humidity between 11% and 97% using by Quartz Crystal Microbalance (QCM) technique. © 2011 Elsevier B.V.

New dicationic bis-imidazolium salts based ionic liquids were synthesized to develop new electrolytes to improve photovoltaic properties of dye sensitized solar cells. Various properties of electrolytes such as viscosities, ion diffusion coefficients, charge transfer resistances and photovoltaic properties were studied. Electrochemical impedance spectroscopy has been performed to investigate diffusion coefficients and charge transfer resistances. Influence of polarity and chain length on the photovoltaic performance, was investigated. A DSSC employing the K34 (butyl-1,4-bis(3-methylimidazolium iodide) gives an open-circuit voltage of 0.64 V, a short-circuit current of 17.11 mA/cm(2) and conversion efficiency of 5.60% under light intensity of 100 mW/cm(2) while the DSSC based on 1-butyl-3-methylimidazolium iodide which is a reference ionic liquid exhibited 5.64% efficiency due to the lowest viscosity, highest diffusion coefficient. (C) 2009 Elsevier Ltd. All rights reserved.

Background and Objective: Pancreatic cancer is very common and difficult to diagnose in early stage. Imaging systems for diagnosing cancer have many disadvantages. However, combining different imaging modalities offers synergistic advantages. Optical imaging is the most multidirectional and widely used imaging modality in both clinical practice and research. Methods: In present study, Zinc(II) phthalocyanine [Zn(II)Pc] was synthesized, labeled with iodine- 131 and in vitro study was carried out. The intracellular uptake studies of radiolabeled Zn(II)Pc were performed in WI-38 [ATCC CCL-75™, tissue: human fibroblast lung] and MIA PaCa-2 [ATCC CRL-1420™, tissue: human epithelial pancreas carcinoma] cell lines. Results: The intracellular uptake efficiency of radiolabeled Zn(II)Pc in MIA PaCa-2 cells was determined two times higher than WI-38 cells. Also, fluorescence imaging (FI) efficiency of synthesized Zn(II)Pc was investigated in MIA PaCa-2 cells and significant uptake was observed. Conclusion: Zn(II)Pc might be used as a new agent for dual fluorescence/nuclear imaging for pancreatic cancer.