Journal of the Iranian Chemical Society最新文献

Chitosan enhancement is essential for establishing an improved adsorbent and binding toxic heavy metal ion. In this investigation, chitosan powder was converted to chitosan beads (CH) for effortless handling and easy penetration into binding sites. The beads were cross-linked with glutaraldehyde, which made them insoluble in acidic media. The cross-linked beads (CCH) were then further grafted with an amino-functionalized solution (5-amino-1,10-phenanthroline) to provide more binding sites. The three sets of chitosan derivatives produced were characterized by Fourier Transform Infrared (FTIR), Scanning Electron Microscope (SEM), Thermogravimetric (TGA), X-ray diffraction (XRD), and BET analysis. The grafted cross-linked chitosan beads (GCCH) were applied in adsorption studies to remove Pb²⁺ and Cu²⁺ ions from the synthetic solutions. The equilibrium experiment data were explained using the Langmuir and Freundlich models, while the kinetics data were studied using pseudo-first- and pseudo-second-order kinetic models. A thermodynamic study was carried out, and the parameters from the study, such as Gibb’s free energy change (∆G^O), enthalpy change (∆H^O), and entropy change (∆H^O), were obtained. The Langmuir model reasonably described the equilibrium data well, with a correlation coefficient (R²) of 0.99 for both metal ions and a maximum binding capacity of 376 mg/g and 348 mg/g for Pb²⁺ and Cu²⁺ ions, respectively. The pseudo-second-order kinetic model gave the line of best fit with an R² value of 0.97. The results from the thermodynamic study showed that binding Pb²⁺ and Cu²⁺ ions onto the adsorbent is endothermic and spontaneous. The spent adsorbent was regenerated with five successive cycles. The study thoroughly covers equilibrium, kinetics, thermodynamics, and desorption, providing insights into adsorption mechanisms. The modified chitosan beads offer increased selectivity, stability, and reusability, making the adsorbent a potential material for heavy metal removal. This method improves adsorption performance while advancing sustainable water treatment.

Cortisol is quantitatively the major glucocorticoid class of steroid hormone involved in the regulation of metabolic homeostasis. Since it is widely used as a biomarker in the diagnosis of human diseases such as Addison’s disease and Cushing’s syndrome, accurate cortisol quantification is still a challenging task. Here, a novel immunoaffinity solid-phase microextraction method, based on carbon fibers immobilized with antibody, was developed for the determination of cortisol coupled with liquid chromatography-tandem mass spectrometry. The limit of detection and quantification of the proposed method were found to be 0.102 and 0.340 ng/mL, respectively. The linearity was satisfactory with the determination coefficient to R² = 0.9996. The relative recoveries were in the range of 98.03 to 113.16% with relative standard deviations ≤ 6.52% (n = 3). This method was successfully applied to the determination of cortisol in human plasma.

In this research, NiCo-MOF was first functionalized with ethylenediamine and then the obtained en/NiCo-MOF nanosheets were loaded with PdCl₂ and MnCl₂. The structures of the resulting nanostructures (Pd@en/NiCo-MOF and Mn@en/NiCo-MOF) were characterized. The size of nanostructures was in the range 3–15 nm and exhibited powerful fluorescence emission bands. The optical band gaps of samples were determined by means of optical absorption spectra and were found to be in the range of 3.8–4.1 eV. The cytotoxic effect of nanostructures was tested against MCF-7 human breast cancer cells by MTT assay and based on the results their effectiveness follows the order of Pd@en/NiCo-MOF > Mn@en/NiCo-MOF > en/NiCo-MOF. The measured IC50 values ranged from 123.766 to 292.737. The expression of caspase 3, 8 and 9 genes in the treated cells of en/NiCo-MOF, Pd@ en/NiCo-MOF and Mn@en/NiCo-MOF was also investigated, and multifold increases compared to the control were observed in all cases.

Manganese-cobalt oxide catalyst (Mn_xCo_3-xO₄-H) with honeycomb structure was prepared from MnCo-BTC (BTC = 1,3,5-benzenetricarboxylic acid). Its honeycomb structure was inherited from MnCo-BTC with nanoneedle structure and Mn_xCo_3-xO₄-H had a bigger surface area (57.63 m²/g) than that (10.06 m²/g) of Mn_xCo_3-xO₄-C prepared by coprecipitation. The Mn_xCo_3-xO₄-H and Mn_xCo_3-xO₄–C catalysts were tested for low-temperature selective catalytic reduction of NO_x with NH₃ (NH₃-SCR) and compared with Mn_xCo_3-xO₄–C catalyst. As a result, Mn_xCo_3-xO₄–H derived from MnCo-BTC exhibited the superior deNO_x activity, which showed 99% NOx conversion at the existence of 100 ppm SO₂ and 200 °C. To characterize the Mn_xCo_3-xO₄–H and Mn_xCo_3-xO₄–C catalysts, X-ray diffraction (XRD), scanning electron microscopy (SEM) and temperature-programmed desorption experiments of SO₂ (SO₂-TPD) were employed. The SO₂-TPD results showed that Mn_xCo_3-xO₄–H had the weaker SO₂ adsorption than Mn_xCo_3-xO₄–C catalyst, resulting in high SO₂ resistance. Finally, based on the in situ DRIFT experiments, it was demonstrated that SO₂ adsorption on Mn_xCo_3-xO₄–H catalyst was suppressed and the effect of SO₂ on the adsorption of the reactant gases was lower than Mn_xCo_3-xO₄–C catalyst, thus resulting good SO₂ resistance. This work expanded the possible applications of metal organic framework i– the SCR field.

Graphical abstract

It was demonstrated that SO₂ adsorption on Mn_xCo_3-xO₄–H catalyst (a) was suppressed and the effect of SO₂ on the adsorption of the reactant gases was lower than Mn_xCo_3-xO₄–C catalyst, thus resulting good SO₂ resistance.

In this study, fourteen novel 2-(benzo[d]thiazol-2-yl)phenol sulfonate compounds (5a–n) were synthesized and characterized using ¹H NMR, ¹³C NMR, and HRMS techniques. The biochemical and physicochemical properties of the sulfonate derivatives were also investigated. As a part of the study, in vitro and in silico enzyme inhibition activities of the sulfonate derivatives against acetylcholinesterase, tyrosinase, and pancreatic lipase enzymes were evaluated. According to the obtained IC₅₀ values, among the novel compounds (5a–n), compounds 5k (0.21 ± 0.06 mM) and 5i (0.22 ± 0.07 mM) were found to be the most effective acetylcholinesterase inhibitors, proving even more effective than the standard tacrine compound (0.34 ± 0.08 mM). The tyrosinase inhibition effect of the compound 5i (0.23 ± 0.07 mM) was found to be the most potent and close to the standard kojic acid (0.06 ± 0.03 mM). Also, the compound 5g (0.21 ± 0.13 mM) was found to be the most effective pancreatic lipase inhibitor, even more effective than the standard orlistat (0.26 ± 0.08 mM). According to the molecular docking studies, the binding affinity of compound 5i was found to be − 6.7 kcal/mol for the tyrosinase, − 9.1 kcal/mol for the acetylcholinesterase, and − 9.9 kcal/mol for the pancreatic lipase. The antioxidant activities of novel compounds were found to be at moderate levels in FRAP, DPPH, CUPRAC, and ABTS methods. Compound 5i (IC₅₀: 10.7 ± 1.1 mM) and compound 5j (IC₅₀: 10.9 ± 1.1 mM) exhibited effective radical scavenging antioxidant properties in DPPH methods. Finally, physicochemical properties, drug similarity, and molecular docking studies were determined using Molinspiration, PreADMET, and AutoDock Vina computational programs. Remarkably, all of in vitro, in silico, and ADMET studies had good correlations with each other and showed moderate to good inhibition properties of the novel compounds against acetylcholinesterase, tyrosinase, and pancreatic lipase enzymes.

This study prepared biochar/zinc oxide composite nanoparticles as a reusable and environmentally friendly biocatalyst. The favorable oxygen-containing functional groups, porous structure, and stability of biochar makes it an excellent support for metal phases, enhancing catalytic activity in reactions. Furthermore, the incorporation of zinc oxide nanoparticles provides a synergistic effect, contributing to a higher surface area and improved active sites for catalytic reactions. The composite material was characterized by various techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray powder diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), wavelength dispersive X-ray spectroscopy (WDX), Brunauer–Emmett–Teller (BET), thermal gravimetry analysis (TGA), and Fourier-transform infrared spectroscopy (FT-IR) to confirm the formation of the nanocomposite and analyze its morphology. The catalytic performance of the biochar/zinc oxide composite was evaluated in the one-pot, three-component synthesis of tetrahydrobenzo[a]xanthenes-11-one derivatives at 100 °C under solvent-free conditions as well as for 5-aminopyrazole-4-carbonitrile derivatives in a 1:2 ethanol–water mixture at 50 °C. The results suggest that this biocatalyst holds great promise for various applications in environmental remediation and sustainable chemistry because of its high efficiency and reusability.

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Recently, researchers have focused on eco-friendly methods for synthesizing gases and chemicals. In photocatalytic N₂ fixation, transition-metal sites adsorb N₂ and weaken its triple bond. Due to the presence of iron in the nitrogenase enzyme, iron-containing catalysts are of interest in nitrogen fixation. PCN-222 (Fe) is among the compounds that have worked well in nitrogen fixation. We report the solvothermal synthesis and testing of the PCN-222 (Fe)/g-C₃N₄ composite in different percentages (10, 20, 30, and 40%) and studied the nitrogen reduction process under visible-light conditions. The PCN-222 (Fe)/g-C₃N₄ composite, we synthesized by a solvothermal method. The highest photocatalytic N2 fixation rate (595.23 μmol g⁻¹ h⁻¹) was observed for the 30% PCN-222 (Fe)/g-C₃N₄ composite, which is almost 2.7 times higher than that of PCN-222 (Fe) alone. To characterize and investigate the synthesized composites, X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), photoluminescence (PL) spectra, Ultraviolet–visible (UV–Vis) spectroscopy, Ion chromatography (IC), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), and Brunauer–Emmett–Teller (BET) were used to study the properties of the synthesized composites.

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This study reports the electropolymerization of 4,4′-methylenedianiline on a glassy carbon electrode (GCE) using cyclic voltammetry. In the subsequent step, a molecularly imprinted polymer was employed to modify the GCE for the indirect detection of acetaminophen (ACT). A potassium hexacyanoferrate (III) (K₃Fe (CN)₆) redox probe was utilized to monitor changes in peak current. Under optimized analytical conditions, the ACT concentration exhibited a linear response in the range of 0.5–20 mg L⁻¹, with a detection limit of 0.2 mg L⁻¹. The sensor's performance was successfully validated through the determination of ACT in blood, ampoule, tablets, and milk, confirming its practical applicability.

This work describes a simple, sensitive, and environmentally friendly analytical technique for the determining of paracetamol in human urine samples and tablet formulation. The current study for the extraction and enrichment of paracetamol is based on the use of rhamnolipid biosurfactants in emulsion-based liquid-phase microextraction. The separation mechanism of paracetamol is based on the emulsion formation of the biosurfactant-rich phase. First, a bioemulsion solution (colloidal phase) was formed and then the analyte was isolated onto the non-aqueous phase. The second step consists of backextraction of the analyte into an aqueous acceptor phase. Finally, the aqueous acceptor phase was withdrawn using a microsyringe and injected into a liquid chromatography instrument for quantitative analysis. The ability of rhamnolipid biosurfactants to form a stable colloidal phase with regions of different polarities can lead to extraction analyte using van der Waals interactions. Considering the biodegradability of biosurfactants and the removal of chemical surfactants in the sample preparation process, the present method is environmentally friendly. Several influencer factors on extraction efficiency including the amount of rhamnolipid biosurfactant, methanol volume, pH, extraction time, ionic strength, and centrifugation time were investigated and optimized. Under optimal conditions, the enrichment factor for the paracetamol was 160. Also, good linearity was obtained in the range 21–100 µg L⁻¹, with coefficients of determination (r²) ˃ 0.993.

Alumina (Al₂O₃)-supported 10-molybdo-2-tungstosilicic green acid catalysts were developed by a novel, cheap, environment-friendly approach and utilized in the synthesis of 2,3-dihydroquinazolin-4(1H)-one derivatives. The structure and morphology of the prepared heteropoly acid catalyst were studied by FT-IR, XRD, BET, FE-SEM, HR-TEM, EDX and TG–DTA techniques. The present catalyst shows maximum conversion efficiency in 2,3-dihydroquinazolin-4(1H)-one’s derivatives synthesis. The activity of H₄SiMo₁₀W₂O₄₀/Al₂O₃ catalysts was tested for the synthesis of 2,3-dihydroquinazolin-4(1H)-ones by the reaction of 2-aminobenzamide and aromatic aldehydes. However, among different catalysts, 20% H₄SiMo₁₀W₂O₄₀/Al₂O₃ has shown better catalytic activity. Besides, the catalyst was recyclable and reused several times without loss of its catalytic activity. Highest yields of products, mild reaction conditions, short reaction times, non-toxicity, economically affordable catalyst, easy separation of products are some of the advantages of this protocol.

Graphical abstract

An economic, sustainable, and straightforward environmentally friendly synthesis of 2,3 dihydroquinazolin-4(1H)-ones derivatives from benzaldehyde (1) and 2-aminobenzamide (2) in presence of catalytic amount of H₄SiMo₁₀W₂O₄₀/Al₂O₃. Excellent yields, reusability of catalyst, green metrics and environmentally sustainability are the main advantages of the present method.