نشریه شیمی کاربردی روز
پیاپی 67 (تابستان 1402)

In this study, amoxicillin from aqueous solutions was adsorbed by activated carbons from eucalyptus leave and wheat straw through adsorption process. The effects of varying parameters such as initial pH of amoxicillin solution, initial concentration of amoxicillin solution, adsorbent dosage, contact time and temperature on the adsorption process were examined. Under optimum conditions containing pH 11, amoxicillin initial concentration 10 mgL-1, adsorbent dosage 0.07 g, contact time 30 and 60 min for eucalyptus leave and wheat straw, respectively, and temperature 25±1oC, maximum adsorption percentages for amoxicillin on eucalyptus leave and wheat straw were obtained 72.4% and 79.2% respectively. In addition, comparison of the experimental results with Langmuir, Freundlich and Temkin adsorption isotherms, showed that the Langmuir isotherm have better fitting with the equilibrium data than the Freundlich isotherm but the fitting with Temkin isotherm is weaker for both adsorbents. Also, thermodynamic parameters of the adsorption such as 〖∆H〗^0 and 〖∆S〗^0 were calculated that theirs negative values showed that the amoxicillin adsorption on eucalyptus leave and wheat straw is an exothermic process and along with decrease of randomness, respectively. Meanwhile, the more negative value of 〖∆G〗^0 at 25oC compared to higher temperatures is a sign of more spontaneous adsorption process at this temperature. In addition, the study of adsorption kinetics showed that the amoxicillin adsorption on both adsorbents is pseudo-second order.

The synthesis of MIL-53(Fe) samples and encapsulation process of phosphomolybdic acid implemented using ultrasound at ambient temperature and atmospheric pressure. Characterization of newly synthesized nanocomposite was carried out using various techniques such as XRD, FT-IR, SEM, EDS, BET and ICP. The catalytic activity of the prepared nanocomposites, PMA@MIL-53(Fe), was tested through the esterification reaction of oleic acid with ethanol under ultrasonic irradiation. Biodiesel production process using certain molar ratio of oleic acid/ethanol, PMA@MIL-53(Fe) as catalyst (10-200 mg) containing different amounts of PMA (0-40%), at different reaction times (5-20 minutes), total energy consumption (in watts, W) and ambient temperature under ultrasound conditions. The operating conditions of each of parameters were varied to study their effects on product yield. The results indicated that the synthesized composites show excellent catalytic activity. by encapsulating heteropoly acids in the MOF network, the challenges of using heteropoly acids, such as low contact surface and high solubility, are largely eliminated. The use of heteropoly acids in the industrial scales shows promise, provided the mentioned problems can be overcome

In this study, a magnetic nanocomposite based on poly (styrene-co-maleic anhydride) (Fe3O4 @ PSMASA) was prepared in three steps. In the first step, poly (styrene-co-maleic anhydride) was prepared from the radical polymerization reaction of styrene and maleic anhydride monomers. In the second step, the iron oxide magnetic nanoparticles prepared by co-precipitation method were functionalized using 3-aminopropyltriethoxycylan (APTES). In the third step, the maleic anhydride ring in the copolymer was modified with sulfanilic acid and amine-activated magnetic iron nanoparticles to form carboxylic acid and sulfonic acid groups on poly (styrene-co-maleic anhydride). The catalytic activity of the resulted Fe3O4 @ PSMASA was investigated in the three-component reaction of isatoic anhydride, amines and aldehydes in ethanol as solvent. This method led to the synthesis of various derivatives of 3,2-dihydroquinazoline-4 (1H) in high yields. The catalyst can be recovered and reused in the reaction without significant loss catalytic activity. The other advantages of this method include high efficiencies, mild reaction conditions, good performance and environmental friendliness.

In this research, graphene oxide (GO) was functionalized with D-penicillamine (DPA) and used to develop an electrochemical sensor for Cu(II) cation. For the successful synthesis of D-penicillamine-functionalized graphene oxide (DPA-GO), Fourier Transfer Infrared Spectroscopy (FTIR), Scanning Electron Microscope (SEM), X-ray diffraction pattern (XRD), and Transmission Electron Microscopy (TEM) are used. DPA-GO modified glassy carbon electrode (DPA-GO / GCE) was prepared and its electrochemical behavior was studied in the presence of Cu(II) cations by cyclic voltammetry, and the results showed the better performance of the DPA-GO-modified electrode compared to unmodified and GO-modified electrode, which related to GO nanostructure and complexing ability of sulfur, nitrogen, and oxygen-containing functional groups in the DPA structure. The prepared sensor was used for the selective and sensitive measurement of Cu(II) cations by square-wave anodic stripping voltammetry (SW-ASV) and the factors affecting the sensor performance were investigated and optimum conditions for sensor operation were determined. Under the optimal conditions, the prepared electrode has a linear response in the range of 1 pM to 0.1 µM and its detection limit was 0.31 pM. The proposed sensor was used satisfactorily to measure copper cation in real water samples with suitable reproducibility and stability.

The luminol chemiluminescent reaction is among well-known quantitative methods in analytical spectroscopy due to its high sensitivity to presence of catalyst and low background signal. In this study, magnetic nanocomposite of Fe3O4/SiO2/TiO2/CoIIITHPP (THPP : tetrahyroxyphenylporphyrin) has been synthesized by co-precipitation method and characterized with fourior transform-infrared (FT-IR), X-ray photoelectron spectroscopy (XRD), vibrating sample magnetometer (VSM), scanning electron microscope (SEM), trasmiddion electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS. For the fist time, this magnetic nanocomposite has been used as catalyst of chemolumincence reactions and showed high catalytic effect on the luminol-H2O2 system. The recovery of catalyst was easily performed by applying the external magnetic field.

In this study, liposome coatings based on phosphatidylethanolamine (by Bingham method) and hydrogel based on salep were produced and loaded with the aim of allicin shelf life study. The structure and morphology of Liposome and hydrogel were studied by FT-IR and SEM. Considering design variables of phosphatidylethanolamine to cholesterol ratio, organic phase solvent to aqueous solvent ratio and liposome formation time, a model was proposed to predict the allicin encapsulation efficiency in liposomes. The optimum condition was achieved by Response Surface Method and software of Design-Expert v.12 where the amount of phosphatidylethanolamine-to-cholesterol 8:1, organic phase to water phase ratio of 4.8:1 and formation time of 158 minutes lead to a yield of 98.99%. For salep-based hydrogel coatings, the maximum encapsulation value was 74.98% at 140 min formation time, while the amount of acrylic acid was 3 ml and the amount of N, N '- methylenebisacrylamide was 0.01 gr. The release behavior of allicin from the liposome coating and the hydrogel coating showed both of them are suitable for drug delivery in the media with pH of 7.4. Investigation of allicin release kinetics from liposomes and hydrogels based on first-order reaction models, Higuchi model and Hixson-crowell equation and Weibull model indicated that Weibull can better fit the experimental data.

The green and efficient three-component reaction between aromatic and heteroaromatic aldehydes, β-ketoesters (ethyl acetoacetate and ethyl benzoylacetate) and hydroxylamine hydrochloride in water and under natural sunlight leads to the formation of various derivatives of 4-arylidene-isoxazole-5(4H)-ones. In this reaction, natural sunlight was used outdoors as a green, cheap, clean, available, safe and non-toxic source of energy. The reactions were carried out in Damghan under sunlight. In this synthetic method using sunlight, the heterocyclization reaction was performed with simple tools and without the use of special equipment. In this three-component reaction, 4-arylidene-isoxazole-5(4H)-ones were synthesized in a range of 17-40 minutes and with yields ranging from 89-97%. The advantages of this suitable and green method can be mentioned abundant sunlight or low-energy visible light as an energy source, no environmental pollution, very mild reaction conditions, simplicity of the reaction method, easy separation, no use of organic solvents and catalysts. Some compounds were tested for antibacterial activity using Staphylococcus aureus and Escherichia coli by disk diffusion method. Some synthesized compounds have good antibacterial activity. The antibacterial activity of synthesized heterocycles is higher against Escherichia coli.

The aim of this research is the fabrication of infrared detector for using in different fields. For this purpose, polyaniline/silver nanowire nanocomposite was synthesized by hard chemical template method. The structural characteristics of the prepared nanocomposite were examined by a scanning electron microscope (SEM) and X-ray diffraction (EDS) spectroscopy. The results of the microscopic analysis showed that the synthetic polyaniline film had a non-uniform porosities with the approximate size distribution in diameter of 270 nm and had contain 1.28 (wt.%) of silver nanowires in the size of 80-100 nm. The results of evaluating the performance of an infrared detector based on the polyaniline/silver nanowire nanocomposite showed that with infrared light, the detector current increases under constant orientation (bias) and returns to its original state when the radiation is stopped. This increase was 4.8%, which indicates an improvement in comparison with prior similar samples. The response and the recovery time were obtained about 30 and 8 s, respectively.

In this study, a colorimetric sensor was introduced to determine citric acid by the indicator displacement assay(IDA) method. The sensor was made from the complex formation reaction between the Chromeazurol S and the gadolinium ions in aqueous solutions. At optimum pH(pH =7.00), Chromeazurol S (yellow) was reacted with gadolinium (III) in a 1: 1 ratio, and the Chromeazurol S-gadolinium color complex solution changed to purple. With the addition of citric acid to the designed sensor, citric acid replaces Chromeazurol S and reacts with gadolinium ion in a 1: 1 ratio. The reason for the displacement of the indicator by the analyte in combination with the gadolinium ion acceptor is that it has a larger citric acid-gadolinium complex formation constant (logKF = 6.86) than the Chromeazurol S-gadolinium formation constant (logKF = 5.67). The linear range of this measurement and detection limit of this sensor (S/N=3) were determined 2.27×10-6 to 112.90×10-6 M and 2.08×10-6, respectively. To determine the selectivity of the designed sensor, the effect of different anions such as pyrophosphate, salicylic acid, periodic acid, benzoic acid, and other compounds on the sensor response under similar conditions was investigated, and no significant color change was observed. It was indicating that the sensor has a high selectivity to measure this analyte. The efficiency of the method was evaluated by measuring citric acid in the orange juice sample by the standard addition method.

Cancer is a huge phenomenon in human society that it observe in developing countries and even more developed countries in terms of economic as well. Colon cancer is created by increasing cancer cells that its main reason is the uncontrollable growth of cells in Colon. In this research, two groups of stable chromene compounds which was calculated in the previous study using bioinformatics software selected and their toxicity effect and the kind of cell death that they cause investigated on HT-29 cancer cell line, which is related to colon cancer. Also, toxicity of 2-amino-4-(4-chlorophenyl)-5-oxo-4H,5H-pyrano [2,3-c] chromene -2-carbonitrile (S1), 2-amino-4-(4-bromophenyl)-5-oxo-4H,5H-pyrano [2,3-c] chromene -2-carbonitrile (S2) which had an appropriate stable determined. At concentrations of 1, 2, 3, 5, 10 and 20 μg / ml, a control group was performed on HT-29 cancer cell lines in comparison with the chemotherapeutic drug Campusar with similar concentrations of the chemotherapy drug using MTT assay. Analysis of data was done by statistical software Graphpad Prism 8 and ANOVA test and ultimately, the type of cell death which created by Flow cytometry technique was examined. The results showed that chromium derivatives by causing apoptosis in HT-29 cancer cells could be further studied as a suitable candidate for the effect on colon cancer.

In this paper, a biocomposite was prepared by liquid phase method using 58S bioactive glass, high molecular weight chitosan and 13X zeolite. Physical characterization of the sample was performed using FT-IR, XRD, FE-SEM and EDX analysis. Results of FT-IR showed the presence of bands related to each component. Also, a comparison between FT-IR spectrum and XRD pattern of chitosan with the ones of prepared composite confirms the cross-linking of chitosan. The compressive strength of the sample was determined using the stress-strain diagram. According to this test, the compressive strength of the sample is 51.43 MPa. Also, the bioactivity of the biocomposite was studied in the simulated body fluid (SBF) at 37 ° C for 3 days, which showed a favorable bioactivity. The XRD pattern and FE-SEM images of the biocomposite before and after immersion in SBF solution show the growth of apatite on the biocomposite. The EDX spectrum also confirms the presence of all components. According to the previous studies, the composite prepared in this paper has more desirable properties than similar composites.

Dairy effluents can be considered as the most polluting wastewater from food processing due to the high pollution-loading and the presence of large amounts of organic compounds such as casein, carbohydrates and fatty acids. Dairy effluents containing fatty acids have adverse effects on the environment and human health due to their stability and biodegradation.Therefore, in the present study, an adsorbent based on polyaniline-magnetic graphene oxide nanocomposite (MGO @ PANI) was synthesized through in situ polymerization of aniline monomer to remove fatty acids in industrial effluents. In situ synthesis is designed to overcome the challenge of nanoparticle aggregation where polymers typically act as nanoreactors and serve as an environment for nanoparticle synthesis. The presence of oxygenated functional groups such as hydroxyl and epoxy groups in graphene oxide (GO) and the presence of nitrogen-containing functional groups such as imine and amine groups in polyaniline all contribute to the absorption of fatty acids. characterization of functional groups, morphology and composition of adsorbent element of MGO @ PANI were performed by FT-IR, FE-SEM and EDX techniques. the parameters affecting the efficiency of fatty acid removal such as pH, adsorbent dose, contact time, concentration and temperature were investigated. The results showed that MGO @ PANI showed high efficiency by removing 94.60% of fatty acids (under optimal conditions of pH 7, dose 15 mg, time 50 minutes at room temperature). The experimental data were well matched with the Freundlich adsorption isotherm (multilayer model of the adsorption process). The study of adsorption kinetics also reveals semi-second-order kinetics. In addition, the thermodynamic study showed that the adsorption of fatty acids on MGO @ PANI is exothermic and the mechanism of physical adsorption.