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1.
Heliyon ; 10(10): e30530, 2024 May 30.
Article in English | MEDLINE | ID: mdl-38770308

ABSTRACT

Organoclays have been proposed as efficient removal agents for colored wastewater treatment. In this study, organo-acid-activated clays were investigated for their ability to remove eosin Y dye molecules. Firstly, the clay was acid activated using sulfuric solution at 90 °C for overnight. Secondly, the resulting materials were treated by hexadecyltetramethylammonium bromide solutions to obtain organo-acid-activated clays. Several techniques were used, such as X-ray diffraction, carbon hydrogen nitrogen analysis, silicon-29 and carbon-13 solid-state nuclear magnetic resonance, and nitrogen adsorption isotherms. The cation exchange capacity values were reduced and the specific surface area values increased from 80.1 m2/g to 183.2 m2/g during the acid activation process. The resulting organo-acid-activated clays had a similar expansion of interlayer spacing of 3.90 nm with less intercalated hexadecyltetramethylammonium surfactants, ranging from 0.80 mmol/g to 1.22 mmol/g; 13C solid NMR indicated that the intercalated surfactants exhibited different degree of conformation. Many factors, including the solid dose, solution pH, amount of intercalated surfactants, and starting eosin-Y concentrations, were studied in relation to the removal capabilities of organo acid-activated clays. Based on the Langmuir model, the removal capacity of the organo acid-activated clays ranged from a minimum of 43.5 mg/g to a maximum of 79.3 mg/g, dependent on the surfactant quantities and acid activation degree. , and the pH. The removal percentage of eosin-Y was increased from 50.5 % to 80.8 % by treating the organo acid-activated clay with HCl solution before the removal procedure. Regeneration and reuse of two selected organo acid-activated clays were carried out for seven successive cycles, and a reduction in the initial efficiency was in the range of 26.4 %-30.1 %. However, for organoclay (without acid activation), approximately 52.1 % efficiency was maintained. Using the Langmuir model and mass balance equations, a single-stage adsorber design was suggested for different dye volumes at a constant starting concentration.

2.
Arch Pharm (Weinheim) ; 357(8): e2400025, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38644337

ABSTRACT

A novel environmentally friendly reversed-phase high-performance liquid chromatography (RP-HPLC) method has been effectively validated for simultaneously measuring a prospective conjunction of tizanidine (TIZ) and etoricoxib (ETC), the combined medicine, in rat plasma. The technique employs diclofenac potassium as the internal standard, guaranteeing dependable and precise outcomes. This study aimed to assess the impact of the suggested combination therapy on treating inflammation resulting from rheumatoid arthritis (RA) in a rat model. The procedure was performed using an Agilent series 1200 model HPLC apparatus. The chromatographic conditions consist of isocratic elution mode, C18 column with dimensions of 150 mm × 4.6 mm × 5 µm, flow rate of 1.5 mL/min, wavelength of 230 nm, temperature of 50°C, and injection volume of 10 µL. The elution was performed using a mobile phase consisting of a phosphate buffer with a pH of 3.5 and acetonitrile in a ratio of 80:20 v/v. Calibration curves were conducted for TIZ and ETC within the 1-50 µg/mL range, demonstrating linear trends with R2 values over 0.999. The effectiveness and eco-friendliness of the proposed method were evaluated using eight separate environmentally conscious metrics. The addition of TIZ and ETC to arthritic rodents amplified these effects significantly. Furthermore, TIZ and ETC significantly reduced serum levels in arthritic rodents, and safety investigations revealed normal complete blood count, liver, and renal functions. TIZ and ETC appear to have antiarthritic, anti-inflammatory, and safe combinations, making them viable future treatment options for RA that are also safe and efficacious. Following validation by United States Food and Drug Administration (US-FDA) rules, all goods met the criteria.


Subject(s)
Arthritis, Rheumatoid , Chromatography, Reverse-Phase , Clonidine , Etoricoxib , Animals , Chromatography, High Pressure Liquid , Rats , Male , Arthritis, Rheumatoid/drug therapy , Arthritis, Rheumatoid/blood , Clonidine/analogs & derivatives , Clonidine/blood , Arthritis, Experimental/drug therapy , Arthritis, Experimental/blood , Arthritis, Experimental/chemically induced , Reproducibility of Results
3.
Biomed J ; : 100714, 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38452973

ABSTRACT

Mitochondria are vital organelles found within living cells and have signalling, biosynthetic, and bioenergetic functions. Mitochondria play a crucial role in metabolic reprogramming, which is a characteristic of cancer cells and allows them to assure a steady supply of proteins, nucleotides, and lipids to enable rapid proliferation and development. Their dysregulated activities have been associated with the growth and metastasis of different kinds of human cancer, particularly ovarian carcinoma. In this review, we briefly demonstrated the modified mitochondrial function in cancer, including mutations in mtDNA, reactive oxygen species production, dynamics, apoptosis of cells, autophagy, and calcium excess to maintain cancer genesis, progression, and metastasis. Furthermore, the mitochondrial dysfunction pathway for some genomic, proteomic, and metabolomics modifications in ovarian cancer has been studied. Additionally, ovarian cancer has been linked to targeted therapies and biomarkers found through various alteration processes underlying mitochondrial dysfunction, notably targeting reactive oxygen species, metabolites, rewind metabolic pathways, and chemo-resistant ovarian carcinoma cells.

4.
Materials (Basel) ; 16(12)2023 Jun 10.
Article in English | MEDLINE | ID: mdl-37374488

ABSTRACT

The mesomorphic stability and optical activity of new group-based benzotrifluoride liquid crystals, (E)-4-(((4-(trifluoromethyl) phenyl) imino) methyl) phenyl 4-(alkyloxy)benzoate, or In, were investigated. The end of the molecules connected to the benzotrifluoride moiety and the end of the phenylazo benzoate moiety have terminal alkoxy groups which can range in chain length from 6 to 12 carbons. The synthesized compounds' molecular structures were verified using FT-IR, 1H NMR, mass spectroscopy, and elemental analysis. Mesomorphic characteristics were verified using differential scanning calorimetry (DSC) and a polarized optical microscope (POM). All of the homologous series that have been developed display great thermal stability across a broad temperature range. Density functional theory (DFT) determined the examined compounds' geometrical and thermal properties. The findings showed that every compound is entirely planar. Additionally, by using the DFT approach, it was possible to link the experimentally found values of the investigated compounds' investigated compounds' mesophase thermal stability, mesophase temperature ranges, and mesophase type to the predicted quantum chemical parameters.

5.
ACS Omega ; 6(13): 9310-9318, 2021 Apr 06.
Article in English | MEDLINE | ID: mdl-33842800

ABSTRACT

The conversion of diethyl ether (DEE) to ethene and ethanol was studied at a gas-solid interface over bulk and supported Brønsted solid acid catalysts based on tungsten Keggin heteropoly acids (HPAs) at 130-250 °C and ambient pressure. The yield of ethene increased with increasing reaction temperature and reached 98% at 220-250 °C (WHSV = 2.2 h-1). The most active HPA catalysts were silica-supported H3PW12O40 and H4SiW12O40 and the bulk heteropoly salt Cs2.5H0.5PW12O40. The HPA catalysts outperformed zeolites HZSM-5 and USY reported elsewhere. A correlation between catalyst activity and catalyst acid strength was established, which indicates that Brønsted acid sites play an important role in DEE elimination over HPA catalysts. The results point to the reaction occurring through the consecutive reaction pathway: DEE → C2H4 + EtOH followed by EtOH → C2H4 + H2O, where ethene is both a primary product of DEE elimination and a secondary product via dehydration of the primary product EtOH. Evidence is provided that DEE elimination over bulk HPA and high-loaded HPA/SiO2 catalysts proceeds via the surface-type mechanism.

6.
Molecules ; 24(16)2019 Aug 20.
Article in English | MEDLINE | ID: mdl-31434234

ABSTRACT

The effect of the counteranion of hexadecyltrimethylammonium salts on the physico-chemical properties of organoclays was investigated, using a selected natural clay mineral with a cation exchange capacity of 95 meq/100 g. The uptake amount of C16 cations was dependent on the hexadecyltrimethylammonium (C16) salt solution used, the organoclay prepared from C16Br salt solution exhibited a value of 1. 05 mmole/g higher than those prepared from C16Cl and C16OH salt solutions. The basal spacing of these organoclays was in the range of 1.81 nm to 2.10 nm, indicating a similar orientation of the intercalated surfactants, and could indicated that the excess amount of surfactants, above the cation exchange capacity of 0.95 meq/g could be adsorbed on the external surface of the clay mineral sheets. These organoclays were found to be stable in neutral, acidic, and basic media. The thermal stability of these organoclays was carried out using thermogravimetric analysis and in-situ X-ray diffraction (XRD) techniques. The decomposition of the surfactant occurred at a maximum temperature of 240 °C, accompanied with a decrease of the basal spacing value close to 1.42 nm. The application of these organoclays was investigated to remove an acidic dye, eosin. The removal amount was related to the initial used concentrations, the amount of the surfactants contents, and to the preheated temperatures of the organoclays. The removal was found to be endothermic process with a maximum amount of 55 mg of eosin/g of organoclay. The value decreased to 25 mg/g, when the intercalated surfactants were decomposed. The reuse of these organoclays was limited to four regeneration recycles with a reduction of 20 to 30%. However, noticeable reduction between 35% to 50% of the initial efficiency, was achieved after the fifth cycle, depending of the used organoclays.


Subject(s)
Cetrimonium Compounds/chemistry , Eosine Yellowish-(YS)/isolation & purification , Surface-Active Agents/chemistry , Carbon/analysis , Clay/chemistry , Eosine Yellowish-(YS)/chemistry , Fluorescent Dyes/chemistry , Fluorescent Dyes/isolation & purification , Magnetic Resonance Spectroscopy , Microscopy, Electron, Scanning , Nitrogen/analysis , Spectroscopy, Fourier Transform Infrared , Temperature , Thermogravimetry , X-Ray Diffraction
7.
Molecules ; 23(9)2018 Sep 06.
Article in English | MEDLINE | ID: mdl-30200610

ABSTRACT

Na-magadiite exchanged with cetyl-trimethylammonium cations provided organophilic silicate materials that allowed for the effective removal of the acidic dye "eosin". The organic cations were intercalated into the interlayer spacing of the layered silicate via an exchange reaction between the organic cations from their bromide salt and the solid Na-magadiite at room temperature. Different techniques were used to characterize the effect of the initial concentration of the surfactant on the structure of the organo-magadiites. The C, H, and N analysis indicated that a maximum of organic cations of 0.97 mmol/g was achieved and was accompanied by an expansion of the basal spacing of 3.08 nm, with a tilted angle of 59° to the silicate layers. The conformation of the organic surfactants was probed using solid-state 13C, finding mainly the trans conformation similar to that of the starting cetyl trimethylammonium bromide salt (C16TMABr). Thermal gravimetric analysis was carried out to study the thermal stability of the resulting organo-magadiites. The intercalated surfactants started to decompose at 200 °C, with a mass loss percentage of 8% to 25%, depending on the initial loading of the surfactant, and was accompanied by a decrease of the basal spacing from 3.16 nm to 2.51 nm, as deduced from the in situ X-ray diffraction studies. At temperatures below 220 °C, an expansion of the basal spacing from 3.15 to 3.34 nm occurred. These materials were used as a removal agent for the anionic dye eosin. The maximum amount of the dye removed was related to the organic cation content and to the initial concentration of eosin, with an improvement from 2.5 mg/g to 80.65 mg/g. This value decreased when the organo-magadiite was preheated at temperatures above 200 °C. The regeneration tests indicated that an 85% removal efficiency was maintained after six cycles of use for the organo-magadiite using Ci of 200 mg/L.


Subject(s)
Coloring Agents/chemistry , Organic Chemicals/chemistry , Water Pollutants, Chemical/chemistry , Water Purification , Adsorption , Aluminum Silicates , Coloring Agents/toxicity , Eosine Yellowish-(YS)/chemistry , Humans , Organic Chemicals/toxicity , Organosilicon Compounds/chemistry , Silicates/chemistry , Surface-Active Agents/chemistry , Temperature , Water/chemistry , Water Pollutants, Chemical/toxicity , X-Ray Diffraction
8.
Molecules ; 23(9)2018 Sep 15.
Article in English | MEDLINE | ID: mdl-30223595

ABSTRACT

The organo-clays (OCs) were prepared by a cation exchange reaction between surfactant (cetyltrimethylammonium, C16TMA) from different counterions (Bromide, Chloride, and Hydroxide). The effect of the counterions was investigated on the physico-chemical properties of the prepared organo-clays. The highest uptake of organic cations (1.60 mmol/g) was achieved using cetyl trimethylammonium bromide solution and the lowest value (0.93 mmol/g) was obtained after modification with cetyl trimethylammonium hydroxide solution starting from the same initial ratio of mmol/g of clay greater than 2.40. The arrangement of C16TMA cations within the interlayer space was assumed to be perpendicular with a tilt angle of 32° to the plane of clay sheets instead of being parallel to the clay surface using C16TMAOH solution at the same ratio. Different techniques were used to characterize these materials. The thermal stability of these organ-clays was investigated using an in-situ X-ray diffraction (XRD) technique. The decomposition of the surfactant moiety occurred at temperatures higher than 215 °C and was accompanied with a shrinkage of the basal spacing value to 1.42 nm. These materials were applied in the removal of an acid dye "eosin." The removed amount of eosin depended on the initial concentrations and the content of surfactants in the organo-clays. The removal of eosin was found to be an endothermic process. The maximum amount of 90 mg/g was achieved. The preheated treatment temperature of two selected OCs did affect the removal properties of eosin. A progressive reduction was observed at temperatures higher than 200 °C. The regeneration of spent OCs was studied and acceptable removal efficiency was maintained after 4 to 6 cycles depending on the used initial concentrations.


Subject(s)
Cetrimonium Compounds/chemistry , Clay/chemistry , Eosine Yellowish-(YS)/chemistry , Cations , Hot Temperature , Molecular Structure , Surface Properties
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