Synthesis and In Vitro Biocompatibility Studies of Novel Alkoxy 4,4-Difluoro-4-bora-3a,4a-diaza-s-indacenes.

BODIPYs are bicyclic aromatic compounds with unique spectroscopic, photophysical, and chemical properties. This study aimed to find BODIPYs with characteristics biocompatible with human cell lines for possible use as imaging agents. Six BODIPY derivatives were synthesised with groups linked to boron, fluorine, phenol, or catechol, resulting in compounds with different physicochemical characteristics. NMR, absorption, and emission spectroscopy and mass spectrometry were subsequently used to characterise them. Afterwards, the biocompatibility of these compounds was evaluated using MTT, SRB, and cellular uptake assays in A549 and H1299 cell lines. Furthermore, a haemolysis assay was performed on human blood cells. To summarise the main results, BODIPYs 1 to 4 showed considerable fluorescence. In contrast, BODIPYs 5 and 6 showed very weak fluorescence, which could be related to the presence of the catechol group and its quenching properties. Regarding biocompatibility, all compounds had metabolic activity and viability above 80% and 70%, respectively. BODIPYs 3 and 6 presented the most consistent data, demonstrating good uptake and, in general, haemolytic activity below 25%. In conclusion, the cytotoxic effects of the compounds were not considerable, and the presence of cyclic alkoxides in BODIPYs 3 and 6 may introduce exciting features that should be highlighted for dual imaging for BODIPY 3 due to its fluorescence or for radioactive labelling in the case of both BODIPYs.

Rhodamine B dye degradation using used face masks-derived carbon coupled with peroxymonosulfate.

Catalytic carbon materials from used face masks (UFM) activated by peroxymonosulfate (PMS) were developed for the degradation of rhodamine B (RhB) dye in aqueous solution. The UFM-derived carbon (UFMC) catalyst had a relatively large surface area as well as active functional groups and promoted the generation of singlet 1O2 and radicals from PMS, giving a high RhB degradation performance (98.1% after 3 h) in the presence of 3 mM PMS. The UFMC could degrade only 13.7% at a minimal RhB dose of 10-5 M. The principal reactive oxygen species of sulphate (SO4•), hydroxyl radicals (•OH), and singlet 1O2 were discovered using electron paramagnetic resonance and radical scavenger studies. Finally, a toxicological plant and bacterial study was performed to demonstrate the potential non-toxicity of the degraded RhB water sample.

Recycling Ophthalmic Lens Wastewater in a Circular Economy Context: A Case Study with Microalgae Integration.

Water pollution poses a global threat to ecosystems and human health and is driven by the presence of various contaminants in wastewater, including nano- and microplastics. Despite the magnitude of this problem, the majority of global wastewater is released untreated into water bodies. To combat this issue, a multi-strategy approach is needed. This study explores a circular economy-based solution for treating emerging pollutants, particularly wastewater from ophthalmic spectacle lens production. Our approach integrates solid waste materials into polymeric and cement matrices while also utilising wastewater for microalgae cultivation. This innovative strategy focuses on biomass generation and economic valorisation. By adopting a circular economy model, we aim to transform environmental pollutants from wastewater into valuable organic products. A key component of our approach is the utilisation of microalgae, specifically Nannochloropsis sp., known for its high lipid content and resilience. This microalgae species serves as a promising biobased feedstock, supporting the production of innovative biobased products, such as biopolymers, for ophthalmic lens manufacturing. Our interdisciplinary approach combines microalgae technology, analytical chemistry, cement production, and polymer processing to develop a sustainable circular economy model that not only addresses environmental concerns, but also offers economic benefits. This study underscores the potential of harnessing high-value products from waste streams and underscores the importance of circular economy principles in tackling pollution and resource challenges.

Development and validation of a RP-HPLC method for the simultaneous analysis of paracetamol, ibuprofen, olanzapine, and simvastatin during microalgae bioremediation.

A rapid reverse phase high-performance liquid chromatography (RP-HPLC) method was developed and validated for the simultaneous quantification of paracetamol, ibuprofen, olanzapine, simvastatin and simvastatin acid in the context of microalgae bioremediation. The method was validated according to the guidelines of the US Food and Drug Administration (FDA), the International Conference on Harmonization (ICH), and Eurachem with respect to system suitability, linearity, accuracy, precision, recovery, limits of detection and quantification, ruggedness, selectivity and specificity. The estimated limits of detection and quantification were, respectively, 0.03 and 0.10 µg mL-1 for paracetamol, 0.03 and 0.09 µg mL-1 for ibuprofen, 0.04 and 0.13 µg mL-1 for olanzapine, 0.27 and 0.83 µg mL-1 for simvastantin, and 0.05 and 0.14 µg mL-1 for simvastantin acid. The inter-day and intra-day precision results were within the acceptance limit of relative standard deviation (%RSD) of less than 2, and the percentage recovery was found to be within the required limits of 80-110%. The developed method is rapid, linear, precise, robust and accurate, and has been successfully applied to the determination of the above common pharmaceutical products during microalgae bioremediation.

Exploration of the cellular effects of the high-dose, long-term exposure to coffee roasting product furan and its by-product cis-2-butene-1,4-dial on human and rat hepatocytes.

Coffee is the most popular hot beverage and caffeine is the most used psychoactive drug in the world. Roasting of coffee beans leads to the generation of minute quantities of undesirable compounds, such as furan. It is now thought that the toxicity of furan derives from its processing by CYP450 family of detoxifying enzymes, leading to the formation of cis-2-butene-1,4-dial (BDA). BDA has known cytotoxicity capacities, binding to proteins, nucleic acids, and glutathione (GSH). BDA also appears to mediate furan's toxic effects, since the inhibition of CYP450 family impedes the aforementioned toxicological effects of furan. There are some studies performed on furan's toxicity, but very few on BDA. Furthermore, the doses used in these studies appear to be fairly high when compared with the expected dosage one could be exposed to in a standard day. As such, to understand if furan and BDA could have toxic effects using more realistic doses and longer time frames, human and rat hepatocytes were exposed to furan or BDA for up to 96 h, and several biochemical parameters were assessed. We report here that human hepatocytes were more sensitive than rat's, in particular to furan, for we show a decrease in MTT reduction, ATP levels and increase in carbonyl formation and 8-OHdG accumulation in the longer time points. BDA was mostly ineffective, which we attribute to a low import rate into the cells. In conclusion, we show that there is potential for harm from furan in high doses, which should be carefully addressed.

Bio-based (chitosan/PVA/ZnO) nanocomposites film: Thermally stable and photoluminescence material for removal of organic dye.

Preparation of hitherto unreported chitosan/poly(vinyl alcohol)/ZnO nanocomposites film (designated as CS/PVA/ZnO) as an efficient bio-based nanocomposites is carried out by a greener approach involving mixing, solution casting and solvent evaporation. Synthesized chitosan-based nanocomposites films are characterized by various analytical techniques such as Fourier-transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The photoluminescent properties of CS/PVA/ZnO films are thoroughly studied and compared with CS/PVA. The outcome suggested that the addition of ZnO nanoparticles increased the intensities and red shifting with respect to CS/PVA. The toxicity of chitosan-based nanocomposites films was examined by MTT assay using the NIH3T3 cells. The viability of chitosan-based nanocomposites films was found to be better than native chitosan and PVA films. Furthermore, the adsorption property of prepared chitosan-based nanocomposites films was tested for the removal of AB 1 dye.

Mesoporous zeolite-chitosan composite for enhanced capture and catalytic activity in chemical fixation of CO2.

Carbon dioxide is one of the greenhouse gases whose increasing concentration in the atmosphere can cause severe problems to both human health and wildlife. A simple ecofriendly procedure was developed to prepare zeolite-chitosan (ZY-CS) composite using solvent exchange followed by calcination for adsorption and chemical fixation of CO2. The as synthesized ZY-CS composite along with zeolite and chitosan were characterized by attenuated total reflection infrared, X-ray diffraction, thermogravimetric, scanning electron microscopy, high-resolution transmission electron microscopy and nitrogen adsorption-desorption isotherms studies. The ZY-CS composite showed enhanced CO2 adsorption capacity compared with pure zeolite and chitosan. The composites also exhibited significant catalytic activity in the chemical fixation of CO2 into cyclic carbonates. This work is foreshadowing the prospect of ZY-CS composite in enhanced capture and catalytic activity in chemical fixation of CO2 for environmental applications.

Carbon dioxide adsorption and cycloaddition reaction of epoxides using chitosan-graphene oxide nanocomposite as a catalyst.

One of today's major challenges is to provide green materials for a cleaner environment. We have conducted studies on carbon dioxide (CO2) adsorption and conversion to valuable products by an ecofriendly approach based in chitosan/graphene oxide (CSGO) nanocomposite film. Rheological behavior indicates that the CSGO has a better solvation property than the pure chitosan. An adsorption capacity of 1.0152mmolCO2/g of CSGO nanocomposite at 4.6bar was observed. The catalytic behavior of the CSGO nanocomposite in the presence of tetra-n-butylammonium iodide (n-Bu4NI) as co-catalyst was evaluated for the cycloaddition of CO2 to epoxides, to give cyclic carbonates, in the absence of any solvent. These results strongly suggest that the CSGO nanocomposite may open new vistas towards the development of ecofriendly material for catalytic conversion and adsorption of CO2 on industrial scale.

Synthesis, physicochemical and optical properties of bis-thiosemicarbazone functionalized graphene oxide.

Fluorescent materials are important for low-cost opto-electronic and biomedical sensor devices. In this study we present the synthesis and characterization of graphene modified with bis-thiosemicarbazone (BTS). This new material was characterized using Fourier transform infrared spectroscopy (FT-IR), Ultraviolet-visible (UV-Vis) and Raman spectroscopy techniques. Further evaluation by X-ray diffraction (XRD), thermo-gravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and atomic-force microscopy (AFM) allowed us to fully characterize the morphology of the fabricated material. The average height of the BTSGO sheet is around 10nm. Optical properties of BTSGO evaluated by photoluminescence (PL) spectroscopy showed red shift at different excitation wavelength compared to graphene oxide or bisthiosemicarbazide alone. These results strongly suggest that BTSGO material could find potential applications in graphene based optoelectronic devices.

On the Performance of Hybrid Functionals for Non-linear Optical Properties and Electronic Excitations in Chiral Molecular Crystals: The Case of Butterfly-Shaped Dicinnamalacetone.

Purely organic chiral molecular assemblies in the solid state hold great potential for non-linear optical applications. Herein, a newly synthesised molecular system is reported, namely, dicinnamalacetone, an otherwise planar molecule that crystallises in a disordered non-centrosymmetric form with four different conformations having an overall predominance of a particular helicity. A combined experimental and theoretical approach, including single-crystal X-ray diffraction, Kurtz-Perry and ab initio methods, is employed to characterise the system and benchmark the performance of hybrid functionals for the prediction of non-linear optical properties and electronic excitations. Comparison of experiment and theory points to a particular set of hybrid functionals that provides an optimal description of this molecular system.

Carbon dioxide capture and conversion by an environmentally friendly chitosan based meso-tetrakis(4-sulfonatophenyl) porphyrin.

We have demonstrated the facile, environmentally friendly and sustainable preparation of chitosan based meso-tetrakis(4-sulfonatophenyl)porphyrin (CS-TPPS) for adsorption and catalytic conversion of carbon-dioxide (CO2). The ionic complexation between chitosan (CS) and meso-tetrakis(4-sulfonatophenyl)porphyrin (TPPS) is confirmed by ultraviolet-visible (UV-vis) and Fourier transform infrared spectroscopy (FTIR). Physical properties, such as crystallinity, thermal stability, surface morphology and porosity were analyzed by X-ray diffraction, thermal analysis, scanning electron microscopy and BET isotherm analysis. CS-TPPS shows adsorption capacity of 0.9mmol CO2/g compared to the adsorption capacity of 0.05mmol CO2/g of pure chitosan and an adsorption capacity of 0.2mmol CO2/g of pure TPPS. It also exhibits higher conversion of CO2 and propylene oxide into cyclic carbonate (66%), compared to pure chitosan (31%). The results are encouraging, and may open new perspectives for the use of biopolymers involving porphyrin based material in environmental and industrial applications.

Flucytosine analogues obtained through Biginelli reaction as efficient combinative antifungal agents.

Invasive fungal infection is a problem that continues to challenge the healthcare sector. New antifungals and new therapeutic strategies are needed to address this challenge. We previously reported that the combination of a synthetic compound with a drug with known mechanism of action is a good strategy to treat aggressive and resistant fungi. Here we revisited our approach and synthesized structural analogues of flucytosine, which is a synthetic antifungal and is being studied for its use in combination therapy with other antifungal drugs. Pyrimidin-one and -thione (often known as DHPM's) as flucytosine analogues were obtained through a Biginelli reaction of corresponding aldehydes, ethylacetoacetate and urea/thiourea. Structure was confirmed by FTIR, 1HNMR, 13CNMR, COSY and MS (ESI+) analysis. All the newly synthesized derivatives were evaluated for the antifungal activity alone and in combination of two most commonly used antifungal drugs, amphotericin B and fluconazole against different clinically isolated Candida albicans strains. Minimum inhibitory concentration results confirmed that BG4 possess high antifungal activity against all the tested strains (MIC = 1-32 µg/ml). For all the combinations with amphotericin B and fluconazole, 37% were synergistic followed by 30% additive and 24% indifferent interactions. Interestingly, 9% antagonistic interaction was observed when BG1 and BG3 were combined with fluconazole, however, no antagonistic interaction was observed with amphotericin B. In-depth studies of all the synergies were done by constructing isobolograms with nine different ratio combinations. These results warrant the use of DHPM derivatives as chemosensitising agents which could lower down the dosages of the antifungal drugs to treat invasive fungal diseases.

Chemically modified amino porphyrin/TiO2 for the degradation of Acid Black 1 under day light illumination.

In this paper, for the first time, chemically modified 5,10,15,20-meso-tetra-(para-amino)-phenyl-porphyrin/TiO2 (TPAPP/TiO2) was prepared and used for the degradation of an azo dye Acid Black 1 (AB 1) under direct sunlight. Initially, TiO2 was prepared by sol-gel method. Before making a TPAPP/TiO2 composite, the surface modification of TiO2 was carried out with glycidoxypropyltrimethoxy silane (GPTMS) which acts as a coupling agent. This is an epoxy terminated silane and could easily bond to the amino group of TPAPP through epoxy cleavage. The formation of TPAPP/TiO2 was confirmed by different characterization techniques such as FT-IR, XRD, SEM and DRS. The photocatalytic activity of TiO2 was highly influenced by TPAPP. A mechanism was proposed for AB 1 degradation by TPAPP/TiO2 under sun light.

Synergistic antifungal effect of cyclized chalcone derivatives and fluconazole against Candida albicans.

The occurrence of invasive fungal diseases, particularly in immunocompromised patients, is life-threatening and increases the economic burden. The rising problem of multi-drug resistance is becoming a major concern for clinicians. In addition, a repertoire of antifungal agents is far less in number than antibacterial drugs. To combat these problems, combination therapy has gained a lot of interest. We previously reported the synergistic interaction of some mono- and bis-dihydropyrimidinone and thione derivatives with fluconazole and amphotericin B for combination antifungal therapy. In this study we used the same approach and synthesized different azole and non-azole derivatives of mono-(M) and bis-(B) chalcones and evaluated their antifungal activity profile alone and in combination with the most commonly used antifungal drug - fluconazole (FLC) - against seven FLC susceptible and three FLC resistant clinically isolated Candida albicans strains. Based on the minimum inhibitory concentration results, the bis-derivatives showed lower MIC values compared to their mono-analogues. Both fractional inhibitory concentration index and isobologram results revealed mostly synergistic, additive or indifferent interactions between the tested compounds and FLC against different Candida isolates. None of the tested compounds showed any effect on energy dependent R6G efflux, revealing that they do not reverse the mechanism of drug efflux. However, surprisingly, these compounds profoundly decreased ergosterol biosynthesis and showed down regulation of ERG11 gene expression, which is the possible mechanism of reversal of azole drug resistance by these compounds. These results provide a platform for further research to develop pyrimidinone/thione ring containing compounds as promising new antifungal agents, which could be used in antifungal combination therapy.

Photophysical Characterization and in Vitro Phototoxicity Evaluation of 5,10,15,20-Tetra(quinolin-2-yl)porphyrin as a Potential Sensitizer for Photodynamic Therapy.

Photodynamic therapy (PDT) is a selective and minimally invasive therapeutic approach, involving the combination of a light-sensitive compound, called a photosensitizer (PS), visible light and molecular oxygen. The interaction of these per se harmless agents results in the production of reactive species. This triggers a series of cellular events that culminate in the selective destruction of cancer cells, inside which the photosensitizer preferentially accumulates. The search for ideal PDT photosensitizers has been a very active field of research, with a special focus on porphyrins and porphyrin-related macrocycle molecules. The present study describes the photophysical characterization and in vitro phototoxicity evaluation of 5,10,15,20-tetra(quinolin-2-yl)porphyrin (2-TQP) as a potential PDT photosensitizer. Molar absorption coefficients were determined from the corresponding absorption spectrum, the fluorescence quantum yield was calculated using 5,10,15,20-tetraphenylporphyrin (TPP) as a standard and the quantum yield of singlet oxygen generation was determined by direct phosphorescence measurements. Toxicity evaluations (in the presence and absence of irradiation) were performed against HT29 colorectal adenocarcinoma cancer cells. The results from this preliminary study show that the hydrophobic 2-TQP fulfills several critical requirements for a good PDT photosensitizer, namely a high quantum yield of singlet oxygen generation (Φ∆ 0.62), absence of dark toxicity and significant in vitro phototoxicity for concentrations in the micromolar range.

Imidazole clubbed 1,3,4-oxadiazole derivatives as potential antifungal agents.

A series of compounds in which 2-(4-ethyl-2-pyridyl)-1H-imidazole was clubbed with substituted 1,3,4-oxadiazole was synthesized and subjected to antifungal activity evaluation. In vitro assays indicated that several clubbed derivatives had excellent antifungal activity against different strains of laboratory and clinically isolated Candida species. Structural Activity Relationship (SAR) studies revealed that the presence and position of substituents on the phenyl ring of the 1,3,4-oxadiazole unit, guides the antifungal potential of the compounds, where compound 4b, 4c and 4g were found to be active against all the tested fungal strains. Impairment of ergosterol biosynthesis upon the concomitant treatment of 4b, 4c and 4g, revealed the possible mechanisms of antifungal action of these compounds. Inhibitors snugly fitting the active site of the target enzyme, as revealed by molecular docking studies, may well explain their excellent inhibitory activity.

Enhanced chitosan-DNA interaction by 2-acrylamido-2-methylpropane coupling for an efficient transfection in cancer cells.

Gene therapy is the treatment of human disorders by the introduction of genetic material to specific target cells of a patient. Chitosan and its derivatives show excellent biological properties including biocompatibility, biodegradability and nonallergenicity. Primary amines of chitosan are responsible for its cationic nature and hence binding and protection of DNA for intracellular delivery. But the transfection efficiency of chitosan based gene transporters is severely hampered by its poor physical properties such as low water solubility and high viscosity. In this study, primary amines of low molecular weight (LMW) chitosan were coupled with 2-acrylamido-2-methylpropane sulphonic acid (AMP) making it water soluble for its application in gene delivery. AMP modified chitosan (CSAMP) showed an enhanced interaction with DNA and a higher buffering capacity due to AMP amines leading to a higher transfection efficiency in cancer cells (A549, HeLa and HepG2) compared to native chitosan and Lipofectamine®. In vivo studies in Balb/c through intravenous injection demonstrated a higher luciferase expression compared to LMW chitosan.

Poly[µ2-aqua-µ4-[1-(4-chloro-phen-yl)-4,4,4-tri-fluoro-butane-1,3-dionato]-potassium].

In the title compound, [K(C10H5ClO2F3)(H2O)] n , the two independent K(+) ions are located on a twofold rotation axis. For each of the cations, the distorted cubic coordination environment is defined by two F and four O atoms of symmetry-related 1,4-chloro-phenyl-4,4,4-tri-fluoro-butane-1,3-dionate anions and by two O atoms of water mol-ecules. The µ4-bridging character of the anion and the µ2-bridging of the water mol-ecule lead to the formation of layers parallel to (100). The coordinating water mol-ecules are also involved in O-H⋯O hydrogen bonds that reinforce the mol-ecular cohesion within the layers, which are stacked along [100]. The ß-diketonate anion is not planar, with an angle of 31.78 (10)° between the mean planes of the diketonate group and the chloro-phenyl ring.

4,7-Diphenyl-1,10-phenanthroline methanol hemisolvate.

The asymmetric unit of the title compound, C24H16N2·0.5CH3OH, is comprised of two independent bathophenanthroline mol-ecules (systematic name: 4,7-diphenyl-1,10-phenanthroline) and one methanol mol-ecule. The bathophenanthroline mol-ecules are not planar as there is a considerable rotation of all terminal phenyl rings with respect to the central phenanthroline units [dihedral angles in the range 52.21 (12)-62.14 (10)°]. In addition, a non-negligible torsion is apparent in one of the phenanthroline units: the angle between the mean planes of the two pyridine rings is 14.84 (13)°. The methanol solvent mol-ecule is linked to both N atoms of a bathophenanthroline mol-ecule through a bifurcated O-H⋯(N,N) hydrogen bond.

1-[(E)-Anthracen-9-yl-methyl-idene]-2-(2,4-di-nitro-phen-yl)hydrazine.

In the title Schiff base, C21H14N4O4, the dihedral angle between the two nitro groups and the central benzene ring are 83.6 (5) and 2.6 (6)°. The anthracene ring system and the benzene ring make a dihedral angle of 0.7 (2)°. Intra-molecular N-H⋯O and C-H⋯N hydrogen bonds occur. In the crystal, C-H⋯O hydrogen bonds link the mol-ecules, forming chains along the b-axis direction.