Antibacterial and antioxidant activity of gold and silver nanoparticles in dextran-polyacrylamide copolymers.

Search for new antimicrobial agents is of great significance due to the issue of antimicrobial resistance, which nowadays has become more important than many diseases. The aim of this study was to evaluate the toxicity and biological effects of a dextran-graft-polyacrylamide (D-PAA) polymer-nanocarrier with/without silver or gold nanoparticles (AgNPs/D-PAA and AuNPs/D-PAA, respectively) to analyze their potential to replace or supplement conventional antibiotic therapy. The toxicity of nanocomplexes against eukaryotic cells was assessed on primary dermal fibroblasts using scratch, micronucleus and proliferation assays. DPPH (2,2-diphenyl-1-picrylhydrazylradical) assay was used to evaluate the antioxidant capacity of D-PAA, AgNPs/D-PAA and AuNPs/D-PAA. DNA cleavage, antimicrobial and biofilm inhibition effects of nanocomplexes were investigated. Nanocomplexes were found to be of moderate toxicity against fibroblasts with no genotoxicity observed. AgNPs/D-PAA reduced motility and proliferation at lower concentrations compared with the other studied nanomaterials. AgNPs/D-PAA and AuNPs/D-PAA showed radical scavenging capacities in a dose-dependent manner. The antimicrobial activity of AgNPs/D-PAA against various bacteria was found to be much higher compared to D-PAA and AuNPs/D-PAA, especially against E. hirae, E. faecalis and S. aureus, respectively. D-PAA, AgNPs/D-PAA and AuNPs/D-PAA showed DNA-cleaving and biofilm inhibitory activity, while AgNPs/D-PAA displayed the highest anti-biofilm activity. AgNPs/D-PAA and AuNPs/D-PAA were characterized by good antimicrobial activity. According to the findings of the study, AgNPs/D-PAA and AuNPs/D-PAA can be evaluated as alternatives for the preparation of new antimicrobial agents, the fight against biofilms, sterilization and disinfection processes. Our findings confirm the versatility of nanosystems based on dextran-polyacrylamide polymers and indicate that AgNPs/D-PAA and AuNPs/D-PAA can be evaluated as alternatives for the preparation of novel antimicrobial agents.

Development of a Cr2AlC MAX phase/g-C3N4 composite-based electrochemical sensor for accurate cabotegravir determination in pharmaceutical and biological samples.

A highly sensitive electrochemical sensor is reported that employs a modified electrode for the precise measurement of cabotegravir, a potent anti-HIV drug. Cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS) were utilized for this purpose. Electrode modification involved the immobilization of Cr2AlC MAX phase/g-C3N4 onto a glassy carbon electrode (GCE) to enhance its electrocatalytic activity and selectivity for cabotegravir detection. Under the optimal experimental conditions, the working potential (vs. Ag/AgCl) was to 0.93 V. The developed sensor exhibited a good linear relationship in the range 0.05 µM to 9.34 µM with a low limit of detection of 4.33 nM, signifying its exceptional sensitivity. Additionally, it demonstrated successful cabotegravir detection in pharmaceutical formulations and biological samples, achieving an RSD below 3.0%. The recoveries fell within the range 97.7 to 102%, confirming the sensor's potential for real-sample applications. This innovative electrochemical sensor represents a significant advancement, providing a simple, reliable, and sensitive tool for the accurate measurement of cabotegravir. Its potential applications include optimizing drug dosages, monitoring treatment responses, and supporting the development of cabotegravir-based pharmaceutical products, thereby contributing to advancements in HIV therapy and prevention strategies.

Synthesis of PES membranes modified with polyurethane-paraffin wax nanocapsules and performance of bovine serum albumin and humic acid rejection.

Membrane fouling is a serious handicap of membrane-based separation, as it reduces permeation flux and hence increases operational and maintenance expenses. Polyurethane-paraffin wax (PU/PW) nanocapsules were integrated into the polyethersulfone membrane to manufacture a composite membrane with higher antifouling and permeability performance against humic acid (HA) and bovine serum albumin (BSA) foulants. All manufactured membranes were characterized by scanning electron microscopy (SEM), scanning electron microscopy-energy dispersive spectrometry (SEM-EDS), and contact angle. The contact angle of the pristine polyethersulfone (PES) membrane was measured 73.40 ± 1.32. With the embedding of nanocapsules, the contact angle decreased to 64.55 ± 1.23 for PES/PU/PW 2.0 wt%, and the pure water flux of all composite membranes increased when compared to pristine PES. The pristine PES membrane also has shown the lowest steady-state fluxes at 45.84 and 46.59 L/m2h for BSA and HA, respectively. With the increase of PU/PW nanocapsule ratio from 0.5 to 1.0 wt%, steady-state fluxes increased from 51.96 to 71.61 and from 67.87 to 98.73 L/m2h, respectively, for BSA and HA. The results depicted that BSA and HA rejection efficiencies of PU/PW nanocapsules blended PES membranes increased when compared to pristine PES membranes.

Antifouling and antibacterial performance evaluation of polyethersulfone membranes modified with AZ63 alloy.

Antibacterial membranes have attracted researchers' interest in recent years as a possible approach for dealing with biofouling on the membrane surface. This research aims to see if blending AZ63 Mg alloy into a polyethersulphone (PES) membrane can improve antifouling and separation properties. The composite membranes' pure water flux continued to increase from pristine PES to PES/AZ63 2.00 wt%. The results showed that PES/AZ63 2.00 wt% membrane supplied the highest permeate flux of E. coli. The steady-state fluxes of AZ63 composite membranes were 113.24, 104.38 and 44.79 L/m2h for PES/AZ63 2.00 wt%, 1.00 wt%, and 0.50 wt%, respectively. The enhanced biological activity of AZ63 was studied based on antioxidant activity, DNA cleavage, antimicrobial, anti-biofilm, bacterial viability inhibition and photodynamic antimicrobial therapy studies. The maximum DPPH scavenging activity was determined as 81.25% with AZ63. AZ63 indicated good chemical nuclease activity and also showed moderate antimicrobial activity against studied strains. The highest biofilm inhibition of AZ63 was 83.25% and 71.63% towards P. aeruginosa and S. aureus, respectively. The cell viability inhibition activity of AZ63 was found as 96.34% against E. coli. The photodynamic antimicrobial therapy results displayed that AZ63 demonstrated 100% bacterial inhibition when using E. coli.

Antimicrobial Effects of Nanostructured Rare-Earth-Based Orthovanadates.

The search for novel antimicrobial agents is of huge importance. Nanomaterials can come to the rescue in this case. The aim of this study was to assess the cytotoxicity and antimicrobial effects of rare-earth-based orthovanadate nanoparticles. The cytotoxicity against host cells and antimicrobial activity of LaVO4:Eu3+ and GdVO4:Eu3+ nanoparticles were analyzed. Effects of nanomaterials on fibroblasts were assessed by MTT, neutral red uptake and scratch assays. The antimicrobial effects were evaluated by the micro-dilution method estimating the minimum inhibitory concentration (MIC) of nanoparticles against various strains of microorganisms, DNA cleavage and biofilm inhibition. GdVO4:Eu3+ nanoparticles were found to be less toxic against eukaryotic cells compared with LaVO4:Eu3+. Both nanoparticles exhibited antimicrobial activity and the highest MIC values were 64 mg/L for E. hirae, E. faecalis and S. aureus shown by GdVO4:Eu3+ nanoparticles. Nanoparticles demonstrated good DNA cleavage activity and induction of double-strand breaks in supercoiled plasmid DNA even at the lowest concentrations used. Both nanoparticles showed the biofilm inhibition activity against S. aureus at 500 mg/L and reduced the microbial cell viability. Taken the results of host toxicity and antimicrobial activity studies, it can be assumed that GdVO4:Eu3+ nanoparticles are more promising antibacterial agents compared with LaVO4:Eu3+ nanoparticles.

Experimental confirmation of antimicrobial effects of GdYVO4:Eu3+ nanoparticles.

Nanotechnology can be applied to design antibacterial agents to combat antibiotic resistance. The aim of the present study was to assess the antimicrobial effects and cytotoxicity of GdYVO4:Eu3+ nanoparticles (NPs). Biofilm inhibition activity, antimicrobial activity, bacterial viability inhibition and DNA cleavage activity of GdYVO4:Eu3+ NPs were studied. In addition, the impact of GdYVO4:Eu3+ NPs on the mitochondrial membrane potential (ΔΨM) of host immune cells and, hence, their apoptosis was analyzed by JC-1 staining using flow cytometry. GdYVO4:Eu3+ NPs demonstrated good antimicrobial, cell viability inhibition and DNA cleavage activities. In addition, GdYVO4:Eu3+ NPs showed good biofilm inhibition activity against S. aureus and P. aeruginosa and inhibition percentages were 89.15% and 79.54%, respectively. However, GdYVO4:Eu3+ NPs promoted mitochondrial depolarization and apoptosis of leukocytes at high concentrations. GdYVO4:Eu3+ nanoparticles are promising antibacterial agents. However, more efforts should be exerted to ensure their safety.

Development of a Novel Nanoarchitecture of the Robust Photosystem I from a Volcanic Microalga Cyanidioschyzon merolae on Single Layer Graphene for Improved Photocurrent Generation.

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.

Radiolabeling, In Vitro Cell Uptake, and In Vivo Photodynamic Therapy Potential of Targeted Mesoporous Silica Nanoparticles Containing Zinc Phthalocyanine.

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 (MSNP5) against pancreatic cancer cells. MSNP5 were labeled with 131I; 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 131I-MSNP5 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/cm2 light dose using and 5-20 µM ZnPc containing MSNP5 concentrations were applied. Histopathological studies revealed that the ratio of necrosis in tumor tissue was higher in the treatment group than the control groups.

Effects of silica nanoparticles on isolated rat uterine smooth muscle.

In spite of their widespread use, toxicity of silica nanoparticles (SiO2 NPs) to mammalian has not been extensively investigated. In the present study, it is aimed to investigate the effects and the mechanism of action of 20 nm sized SiO2 NPs on isolated uterine smooth muscle. A total number of 84 preparations of uterine strips were used in the experiments. Study was designed as four groups: group I (control), group II (0.2 mM SiO2 NPs), group III (0.4 mM SiO2 NPs) and group IV (0.8 mM SiO2 NPs). Spontaneous contractions were recorded using mechanical activity recording system. Superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities and malondialdehyde (MDA) levels were measured using the spectrophotometric methods. Apoptosis of the cells was detected using immunofluorescence staining assay. SiO2 NP distribution and ultrastructural changes were determined by transmission electron microscopy. In groups II-IV, the frequency of contraction was significantly lower than that of the group I, whereas the contraction energy significantly decreased only in group IV. SOD and GSH-Px activities were significantly lower in experimental groups compared to the control group. MDA level and apoptotic cells were significantly higher in all SiO2 groups compared to the control group. Numerous SiO2 NPs in cytoplasm and connective tissue were observed in all dose groups. These findings showed that 20 nm sized SiO2 NPs enter the connective tissue and cytoplasm of uterine muscle cells and cause oxidative stress and apoptosis leading to impaired uterine contractile activity.

Selective Photokilling of Human Pancreatic Cancer Cells Using Cetuximab-Targeted Mesoporous Silica Nanoparticles for Delivery of Zinc Phthalocyanine.

BACKGROUND: Photodynamic therapy (PDT) is a non-invasive and innovative cancer therapy based on the photodynamic effect. In this study, we sought to determine the singlet oxygen production, intracellular uptake, and in vitro photodynamic therapy potential of Cetixumab-targeted, zinc(II) 2,3,9,10,16,17,23,24-octa(tert-butylphenoxy))phthalocyaninato(2-)-N29,N30,N31,N32 (ZnPcOBP)-loaded mesoporous silica nanoparticles against pancreatic cancer cells. RESULTS: The quantum yield (ΦΔ) value of ZnPcOBP was found to be 0.60 in toluene. In vitro cellular studies were performed to determine the dark- and phototoxicity of samples with various concentrations of ZnPcOBP by using pancreatic cells (AsPC-1, PANC-1 and MIA PaCa-2) and 20, 30, and 40 J/cm² light fluences. No dark toxicity was observed for any sample in any cell line. ZnPcOBP alone showed a modest photodynamic activity. However, when incorporated in silica nanoparticles, it showed a relatively high phototoxic effect, which was further enhanced by Cetuximab, a monoclonal antibody that targets the Epidermal Growth Factor Receptor (EGFR). The cell-line dependent photokilling observed correlates well with EGFR expression levels in these cells. CONCLUSIONS: Imidazole-capped Cetuximab-targeted mesoporous silica nanoparticles are excellent vehicles for the selective delivery of ZnPcOBP to pancreatic cancer cells expressing the EGFR receptor. The novel nanosystem appears to be a suitable agent for photodynamic therapy of pancreatic tumors.

Synthesis and performance of antifouling and self-cleaning polyethersulfone/graphene oxide composite membrane functionalized with photoactive semiconductor catalyst.

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.

Nuclear imaging potential and in vitro photodynamic activity of symmetrical and asymmetrical zinc phthalocyanines.

Photodynamic therapy (PDT) is based on exposing a light-sensitive material that has been localized in target tissues with visible light. In the current study, symmetric Zn(II) octaoctadodecylphthalocyanine (1) and the asymmetrically substituted hydroxyhexyloxy derivative (2) were examined as a multifunctional agent for tumour nuclear imaging and for PDT potential. Zn(II)Pc 1 and Zn(II)Pc 2 were radiolabelled with (131) I using an iodogen method with high efficiency (93.5 ± 3.5% and 93.0 ± 2.8%, respectively) under the optimum conditions. Biodistribution study results showed that radiolabelled Zn(II)Pc 1 had a high uptake in the large intestine and unchanging uptake in the ovary. However, radiolabelled Zn(II)Pc 2 uptake was statically significant in the large intestine, pancreas, ovary and lung. For the PDT studies, EMT6/P (mouse mammary cell line) and HeLa (cervical adenocarcinoma cell line) with Zn(II)Pc 1 and Zn(II)Pc 2 were exposed to red light (650 nm) at 10-30 J/cm(2) . Zn(II)Pc 1 and Zn(II)Pc 2 had a good PDT efficacy in the EMT6/P cell line. In conclusion, radiolabelled Zn(II)Pc 1 might be a promising imaging agent for pancreas, ovary and colon tumours. However, the radiolabelled Zn(II)Pc 2 might be a promising nuclear imaging and PDT agent for colon, lung, pancreas and ovary tumours.

SiO2 Nanoparticule-induced size-dependent genotoxicity - an in vitro study using sister chromatid exchange, micronucleus and comet assay.

Fine particles with a characteristic size smaller than 100 nm (i.e. nanoparticlesspread out in nowadays life. Silicon or Si, is one of the most abundant chemical elements found on the Earth. Its oxide forms, such as silicate (SiO4) and silicon dioxide, also known as silica (SiO2), are the main constituents of sand and quartz contributing to 90% of the Earth's crust. In this work, three genotoxicity systems "sister chromatid exchange, cytokinesis block micronucleus test and single cell gel electrophoresis (comet) assay" were employed to provide further insight into the cytotoxic and mutagenic/genotoxic potential of SiO2 nanoparticules (particle size 6 nm, 20 nm, 50 nm) in cultured peripheral blood lymphocytes as in vitro. It was observed that there is a significant decrease in Mitotic index (MI), Cytokinesis block proliferation index (CBPI), proliferation index (PRI) values expressed as Cell Kinetic parameters compared with negative control (p < 0.05). There is a statistically significant difference between negative control culture and culture exposed to SiO2 (6 nm, 20 nm, 50 nm) (p < 0.01, p < 0.01, p < 0.05, respectively). It is found that SiO2 nanoparticles at different size (6, 20, 50 nm) progressively increased the SCE frequency and DNA damage on the basis the AU values compared with negative control (p < 0.05). Results showed that the genotoxic/mutagenic and cytotoxic effects of SiO2 nanoparticules is dependent to particule size.

The Syntheses of Chromium Aluminum Carbide (Cr2AlC) MAX Phase and Cr2CTx MXene and Investigation of Their Antimicrobial Properties.

Chromium aluminum carbide (Cr2AlC) MAX phase and Cr2CTx (MXene-Cr) were synthesized by the pressureless sintering method and hydrothermal method, respectively. In addition to this, the free radical scavenging activities (FRSA) of MAX-Cr phase and MXene-Cr compounds were tested and compared with ascorbic acid and trolox as standard compounds. The obtained FRSA results of MAX-Cr phase and MXene-Cr were 42.82 and 59.64%, respectively, at 100 mg/L concentration. MXene-Cr showed a 66.90% inhibitory effect on α-amylase at 200 mg/L. The DNA nuclease activity of compounds was determined to be extremely satisfactory at 50, 100, and 200 mg/L concentrations. Moreover, the prepared MAX-Cr phase and MXene-Cr were investigated for antimicrobial activity against six bacterial and two fungal strains by the broth microdilution method. Compounds provided more significant inhibition against Gram-positive bacteria than Gram-negative bacteria and fungi. MAX-Cr phase and MXene-Cr almost completely inhibited microbial cell viability at a 25 mg/L concentration. Additionally, MXene-Cr showed 89.86% and 87.01% antibiofilm activity against S. aureus and P. aeruginosa, respectively, while the antibiofilm activity of the MAX-Cr phase was over 90%.

Water-splitting catalysis and solar fuel devices: artificial leaves on the move.

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.

Antimicrobial activity and cytotoxicity study of cerium oxide nanoparticles with two different sizes.

The control over bacterial diseases requires the development of novel antibacterial agents. The use of antibacterial nanomedicines is one of the strategies to tackle antibiotic resistance. The study was designed to assess the antimicrobial activity of cerium oxide (CeO2 ) nanoparticles (NP) of two different sizes (CeO2 NP1 [1-2 nm] and CeO2 NP2 [10-12 nm]) and their cytotoxicity towards eukaryotic cells. The antimicrobial activity, effects of nanoparticles on DNA cleavage, microbial cell viability, and biofilm formation inhibition were analyzed. The impact of cerium oxide nanoparticles on eryptosis of erythrocytes was estimated using annexin V staining by flow cytometry. The newly synthesized CeO2 NP1 and CeO2 NP2 displayed moderate antimicrobial activities. CeO2 NP1 and CeO2 NP2 exhibited single-strand DNA cleavage ability. CeO2 NPs were found to show 100% microbial cell viability inhibition at a concentration of 500 mg/L. In addition, CeO2 NP1 and CeO2 NP2 inhibited the biofilm formation of S. aureus and P. aeruginosa. Larger cerium oxide nanoparticles were found to be less toxic against erythrocytes compared with the smaller ones. CeO2 nanoparticles demonstrate moderate antimicrobial activity and low cytotoxicity towards erythrocytes, which make them promising antibacterial agents.

Boron-based magnesium diboride nanosheets preparation and tested for antimicrobial properties for PES membrane.

Antimicrobial resistance to antibiotics for current bacterial infection treatments is a medical problem. 2D nanoparticles, which can be used as both antibiotic carriers and direct antibacterial agents due to their large surface areas and direct contact with the cell membrane, are important alternatives in solving this problem. This study focuses on the effects of a new generation borophene derivative obtained from MgB2 particles on the antimicrobial activity of polyethersulfone membranes. MgB2 nanosheets were created by mechanically separating magnesium diboride (MgB2) particles into layers. The samples were microstructurally characterized using SEM, HR-TEM, and XRD methods. MgB2 nanosheets were screened for various biological activities such as antioxidant, DNA nuclease, antimicrobial, microbial cell viability inhibition, and antibiofilm activities. The antioxidant activity of nanosheets was 75.24 ± 4.15% at 200 mg/L. Plasmid DNA was entirely degraded at 125 and 250 mg/L nanosheet concentrations. MgB2 nanosheets exhibited a potential antimicrobial effect against tested strains. The cell viability inhibitory effect of the MgB2 nanosheets was 99.7 ± 5.78%, 99.89 ± 6.02%, and 100 ± 5.84% at 12.5 mg/L, 25 mg/L, and 50 mg/L, respectively. The antibiofilm activity of MgB2 nanosheets against S. aureus and P. aeruginosa was observed to be satisfactory. Furthermore, a polyethersulfone (PES) membrane was prepared by blending MgB2 nanosheets from 0.5 wt to 2.0 wt %. Pristine PES membrane also has shown the lowest steady-state fluxes at 30.1 ± 2.1 and 56.6 L/m2h for BSA and E. coli, respectively. With the increase of MgB2 nanosheets amount from 0.5 to 2.0 wt%, steady-state fluxes increased from 32.3 ± 2.5 to 42.0 ± 1.0 and from 15.6 ± 0.7 to 24.1 ± 0.8 L/m2h, respectively for BSA and E. coli. E. coli elimination performance of PES membrane coated with MgB2 nanosheets at different rates and the membrane filtration procedure was obtained from 96% to 100%. The results depicted that BSA and E. coli rejection efficiencies of MgB2 nanosheets blended PES membranes increased when compared to pristine PES membranes.

Water-Based Synthesis of Copper Chalcogenide Structures and Their Photodynamic Immunomodulatory Activities on Mammalian Macrophages.

Generation of novel and versatile immunomodulatory agents that could suppress excessive inflammation has been crucial to fight against chronic inflammatory and autoimmune disorders. Immunomodulatory agents regulate the function of immune system cells to manage their activities. Current therapy regimens for the inflammatory and autoimmune disorders rely on immunomodulatory drug molecules but they are also associated with unwanted and severe side effects. In order to prevent the side effects associated with drug molecules, the field should generate novel immunomodulatory drug candidates and further test them. Moreover, the generation of photodynamic immunomodulatory molecules would also decrease possible side effects. Photodynamic activation enables specific and localized activation of the active ingredients upon exposure to a certain wavelength of light. In our study, we generated copper-based chalcogenide structures in gel and nanoparticle form by using a water-based method so that they are more biocompatible.After their chemical characterization, they were tested on mammalian macrophages in vitro. Our results suggest that these molecules were anti-inflammatory in dark conditions and their anti-inflammatory potentials significantly increased upon xenon light treatment. We are presenting novel photodynamic immunomodulatory agents that can be used to suppress excessive inflammation in disease conditions that have been associated with excessive inflammation.

Development of antimicrobial nanocomposite scaffolds via loading CZTSe quantum dots for wound dressing applications.

The antimicrobial properties of scaffolds designed for use in wound healing are accepted as an important factor in the healing process to accelerate the wound healing process without causing inflammation. For this purpose, chitosan-polyvinyl alcohol composite membranes loaded with Cu2ZnSnSe4quantum dots (CZTSe QDs) as an antibacterial and cytocompatible biomaterial to regulate the wound healing process were produced. CZTSe QDs particles were synthesized under hydrothermal conditions. Polymer-based nanocomposites with different concentrations of the synthesized nanoparticles were produced by the solvent casting method. After detailed physicochemical and morphological characterizations of CZTSe QDs and composite membranes, antibacterial activities and cell viability were extensively investigated against gram-positive and gram-negative bacterial and yeast strains, and L929 mouse fibroblast cells lines, respectively. The results show that the preparation of composite scaffolds at a QDs concentration of 3.3% by weight has the best antimicrobial activity. Composite scaffold membranes, which can be obtained as a result of an easy production process, are thought to have great potential applications in tissue engineering as wound dressing material due to their high mechanical properties, wettability, strong antibacterial properties and non-toxicity.

Antiinflammatory photodynamic therapy potential of polyoxyethylene-substituted perylene diimide, nitrocatechol, and azo dye.

Photodynamic therapy (PDT) applications enable light-controlled activation of drug candidates instead of their constitutive activities to prevent undesired side effects associated with their constant activities. A specific wavelength of light is utilized to enable electron mobility in the chemical structure, which results in differential activities that may alter cell viability and cellular functions. Canonical photodynamic therapy applications mostly focus on cytotoxicity-based antimicrobial and anticancer properties of the PDT agents. In this study, we focused on subtoxic concentrations of three different molecules containing polyoxyethylene group and examined their antiinflammatory activities on stimulated mammalian macrophages. Stimulated macrophages produce proinflammatory cytokines TNF and IL6. In the presence of a light source, our PDT agents were activated for 5 and 10 min during their application to the macrophages. Based on the ELISA results, the compounds had anti-inflammatory PDT activities. Trypan blue staining results suggest that these derivatives exerted their activities without leading to cytotoxicity. Our results suggest noncanonical PDT applications of these derivatives that can alter cellular activities without leading to cell death.