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Biochar production from unconventional biomass, specifically onion peel (OP) and chicken feathers (CF), was investigated in this study. Two distinct biochars were produced by doping each biomass with the other, with the aim of exploring the synergistic effects of different feedstock combinations on biochar properties. The biochar production process was conducted using a retort heating method and characterized using several techniques. A yield of 36 % was obtained for OP-doped biochar (OP92CF8-BC) and 23 % for CF-doped biochar (F92OP8-BC). Fourier Transform Infrared Spectroscopy analysis revealed characteristic functional groups from cellulose, hemicellulose, and lignin in OP92CF8-BC, while CF92OP8-BC displayed keratin-related peaks. Scanning Electron Microscopy imaging showed surface morphology differences, with OP92CF8-BC exhibiting a rougher and more porous structure compared to CF92OP8-BC. Energy-Dispersive X-ray Spectroscopy analysis confirmed the elemental composition, with OP92CF8-BC having higher carbon, calcium, and sulfur contents and CF92OP8-BC having higher nitrogen and oxygen contents. The biochar had specific surface areas of 342.4 and 200.80 m2/g for OP92CF8-BC and CF92OP8-BC, respectively. According to the results, using biochar treatments-more especially, CF92OP8-BC-can significantly enhance cob weight. This could be good for agricultural productivity. These findings highlight the influence of feedstock composition on the properties of biochar and provide insights for its potential applications in soil amendment and pollutant removal.
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This study aimed to synthesize ecofriendly and low-cost surfactant-based sugar, HA-ST, under mild conditions and a short route via an opening ring of hexadecylsuccinic anhydride (HA) using starch (ST). HA-ST's chemical structure, thermal behavior, and surface activity were evaluated using Fourier Transform Infrared (FTIR) spectroscopy, thermogravimetric analysis, and a pendant drop technique. The results indicated HA-ST formation, thermal stability, and surface activity. HA-ST's green character, low cost, and surface activity recommended its use as a demulsifier for crude oil emulsions at different affecting parameters such as temperature, seawater ratio (SR), demulsifier concentration, demulsification time (DT), and pH. HA-ST demulsification efficiency (DE) was evaluated and compared with a commercial demulsifier (CD). The results showed improved HA-ST's DE with rising temperature, SR, demulsifier concentration, DT, and pH. The DE of HAST reached 100% at 50% of SR and 250 ppm of demulsifier concentration; the same results were obtained using CD. In contrast, HA-ST gave relatively lower DE at low SR (10%) with a value of 70% than the obtained using CD with a value of 75%. The green character, low cost, and DE of HA-ST make it suitable for demulsifying crude oil emulsions, especially those containing more than 30% seawater, compared with CD, which commonly contains two or more traditional surfactants.
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Trypsin is a serine protease, an important digestive enzyme that digests the proteins in the small intestine. In the present study, we have investigated the interaction of safranal, a major saffron metabolite, with trypsin using spectroscopic and molecular docking analyses. Fluorescence emission spectra of trypsin were largely affected by the inner filter effect from safranal; that's why these were corrected using the standard procedure. The corrected fluorescence spectra have shown that the safranal quenched the intrinsic fluorescence of trypsin with a blue shift in the wavelength of emission maximum, which revealed that the microenvironment of the fluorophore became more hydrophobic. There was approximately 1: 1 fair binding between them, which increased with a rise in temperature. The interaction was favored, principally, by hydrophobic forces, and there was an efficient energy transfer from the fluorophore to the safranal. Synchronous fluorescence spectra suggested that the tryptophan residues were the major ones taking part in the fluorescence quenching of trypsin. Safranal also influenced the secondary structure of trypsin and caused partial unfolding. Molecular Docking and the Molecular Dynamics simulation of the free and complexed trypsin was also carried out. Safranal formed a stable, non-covalent complex within the S2'-S5' subsite. Moreover, two nearby tyrosine residues (Tyr39 and Tyr151) stabilized safranal through π-π interactions. Additionally, the presence of safranal led to changes in the protein flexibility and compactness, which could indicate changes in the surrounding of tryptophan residues, impacting their fluorescence. Furthermore, a loss in compactness is in line with the partial unfolding observed experimentally. Thus, both experimental and computational studies were in good agreement with each other.
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Crocus , Cicloexenos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Terpenos , Tripsina , Tripsina/química , Tripsina/metabolismo , Crocus/química , Cicloexenos/química , Cicloexenos/metabolismo , Terpenos/química , Terpenos/metabolismo , Ligação Proteica , Interações Hidrofóbicas e Hidrofílicas , Espectrometria de FluorescênciaRESUMO
Plant extracts used as corrosion inhibitor for mild steel usually degrade as the temperature increases above room temperature. In this study, we used Anacardium occidentale (cashew leaf) extract to synthesize silver nanoparticles for improving mild steel's inhibition stability under salinized conditions. Cashew leaves were used as a reducing agent to synthesise silver nanoparticles. The functional group of the silver nanoparticles was determined using Fourier transform infrared spectroscopy. Electrochemical impedance spectroscopy and potentiodynamic polarisation were used to study the corrosion behaviour under simulated seawater by varying the silver nanoparticle concentration between 0.1 and 0.3 g L-1. Scanning electron microscopy and atomic force microscopy were used to obtain information about the surface of the corroded sample. The green silver nanoparticles reduced the corrosion of mild steel up to 90.5% at 40 °C and 90% at 80 °C. At 80 °C, the AgNPs are biochemically and thermally stable, exhibiting a 90% inhibition efficiency. It was established that silver nanoparticles from cashew leaves can be used to improve the stability of mild steel in simulated seawater.
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Diabetes-induced kidney damage represents a substantial health hazard, emphasizing the imperative to explore potential therapeutic interventions. This study investigates the nephroprotective activity of flavonoid-rich extracts from Hibiscus sabdariffa leaves in streptozotocin-induced diabetic rats. The flavonoid-rich extracts of H. sabdariffa leaves was obtained using a standard procedure. The animals were induced with streptozotocin and thereafter treated with both low (LDHSFL) and high doses (HDHSFL) of flavonoid-rich extracts from H. sabdariffa leaves and metformin (MET), and other groups are diabetic control (DC) and normal control (NC). The study assesses diverse renal parameters, encompassing kidney redox stress biomarkers, serum electrolyte levels, kidney inflammatory biomarkers, serum concentrations of creatinine, urea, and uric acid, kidney phosphatase activities, renal histopathology, and relative gene expressions of kidney injury molecule-1 (KIM-1) and transforming growth factor beta-1 (TGF-1ß), comparing these measurements with normal and diabetic control groups (NC and DC). The findings indicate that the use of extracts from H. sabdariffa leaves markedly (p < 0.05) enhanced renal well-being by mitigating nephropathy, as demonstrated through the adjustment of various biochemical and gene expression biomarkers, indicating a pronounced antioxidative and anti-inflammatory effect, improved kidney morphology, and mitigation of renal dysfunction. These findings suggest that H. sabdariffa leaf flavonoid extracts exhibit nephroprotective properties, presenting a potential natural therapeutic approach for the treatment of diabetic nephropathy.
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Warfarin is a cardiovascular drug, used to treat or inhibit the coagulation of the blood. In this paper, we have studied the interaction of lysozyme with warfarin using several experimental (fluorescence, UV-visible and circular dichroism spectroscopies) and computational (molecular docking, molecular dynamics and DFT) approaches. Experimental studies have suggested that there was a strong interaction between lysozyme and warfarin. Inner filter effect played important role in fluorescence experimental data which show that the emission intensity of lysozyme decreased on the addition of warfarin, however, after inner filter effect correction the actual outcome turned out be the fluorescence enhancement. The extent of binding, increased with temperature rise. The interaction was primarily taken place via the dominance of hydrophobic forces. Small amount of warfarin didn't influence the secondary structure of lysozyme; however, the higher concentration of warfarin caused a decrease in the helicity of the protein and a consequent partial unfolding. Molecular docking studies were also performed which revealed that warfarin binds with lysozyme mainly with hydrophobic forces along with a significant contribution of hydrogen bonding. The flexibility of warfarin played important role in fitting the molecule into the binding pocket of lysozyme. Frontier molecular orbitals of warfarin, using DFT, in free as well as complexed form have also been calculated and discussed. Molecular dynamics simulations of unbound and warfarin bound lysozyme reveal a stable complex with slightly higher RMSD values in the presence of warfarin. Despite slightly increased RMSF values, the overall compactness and folding properties remain consistent, emphasizing strong binding towards lysozyme through the results obtained from intermolecular hydrogen bonding analysis. Essential dynamics analysis suggests warfarin induces slight structural changes without significantly altering the conformation, additionally supported by SASA patterns. Aside from the examination of global and essential motion, the MM/PBSA-based analysis of binding free energy elucidates the significant binding of warfarin to lysozyme, indicating a binding free energy of -13.3471 kcal/mol.
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This paper delves into the polymorphism of 2-[3-(trifluoromethyl)anilino]benzoic acid, commonly referred to as flufenamic acid (FA), a pharmaceutical agent employed in treating inflammatory conditions. The central focus of the study is on a newly unearthed solvatomorphic structure of FA in methanol (FAM), and a thorough comparison is conducted with the commercially available standard structure. Employing a comprehensive approach, including X-ray crystallography, Hirshfeld surface analysis, density functional theory (DFT), molecular docking, and molecular dynamics (MD) simulations, the research aims to unravel the structural and functional implications of solvatomorphism. The X-ray crystal structure analysis brings to light notable differences between the standard FA and solvatomorphic FAM, showcasing variations in intermolecular interactions and crystal packing. Key features such as hydrogen bonding, π···π stacking, and C-H···π interactions are identified as influential factors shaping the stability and conformation of the compounds. Hirshfeld surface analysis further quantifies the nature and contribution of intermolecular interactions, providing a comprehensive perspective on molecular stability. Density functional theory offers valuable electronic structure insights, highlighting disparities in frontier molecular orbitals between FA and FAM. Molecular docking studies against prostaglandin D2 11-ketoreductase explore potential drug interactions, unveiling distinct binding modes and hydrogen bonding patterns that shed light on how the solvatomorphic structure may impact drug-target interactions. In-depth molecular dynamics simulations over 100 ns investigate the stability of the protein-ligand complex, with root mean square deviation and root mean square fluctuation analyses revealing minimal deviations and affirming the stability of FAM within the active site of the target protein.
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In this study, inexpensive magnetite nanoparticles (Fe3O4) were prepared and applied to oil spill remediation. To do so, two novel hydrophobic amides, HADN and HATN, were prepared and applied to Fe3O4 surface modification, producing HAN-Fe3O4 and HAT-Fe3O4, respectively. The efficiency of HAN-Fe3O4 and HAT-Fe3O4 for oil spill remediation (EOSR) was investigated using different HAN-Fe3O4 and HAT-Fe3O4 weights and at various contact times. The data indicated that the EOSR increased with increased HAN-Fe3O4 and HAT-Fe3O4 weights, as their EOSR reached 100% and 89%, respectively, using 100 mg. The results also revealed that the optimum time for HAN-Fe3O4 and HAT-Fe3O4 (50 mg) to achieve the highest EOSR is 8 min, as their EOSR reached 98% and 84%, respectively, at this time. In addition, HAN-Fe3O4 exhibited higher EOSR than HAT-Fe3O4, which could be linked to the presence of an aromatic ring in HADN that is used for surface modification of Fe3O4, making them more compatible with crude oil components.
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Amidas , Recuperação e Remediação Ambiental , Interações Hidrofóbicas e Hidrofílicas , Nanopartículas de Magnetita , Poluição por Petróleo , Nanopartículas de Magnetita/química , Amidas/química , Recuperação e Remediação Ambiental/métodos , PetróleoRESUMO
This work assessed the ability of Musa acuminata peduncle juice extract to sustainably inhibit mild steel under salinized conditions. The effort sought to ascertain the new active material's inhibitory efficacy for inhibiting metal corrosion in seawater. M. acuminata peduncle juice was extracted from the M. acuminata peduncle. The functional group of the M. acuminata pedal juice was determined using Fourier transform infrared spectroscopy. The corrosion behavior was assessed using electrochemical impedance spectroscopy and potentiodynamic polarization by varying the M. acuminata peduncle juice at 0.1, 0.2, and 0.3 g L-1 for 300 K, 310 K, and 320 K, respectively. Scanning electron microscopy provided an image of the surface morphology of mild steel. Reduced corrosion current (icorr) was observed when M. acuminata pedal juice was present according to potentiodynamic polarization and studies. Moreover, adding M. acuminata peduncle juice increases resistance capacity transfer (Rct). The potentiodynamic polarization approach was used to obtain the optimum inhibitory efficiency (%IE) at 0.3 g L-1 doses with 88.0% efficiency at 300 K. The addition of M. acuminata peduncle juice results in a smoother, mild steel morphology than the surface without inhibitor additions. The molecules of active chemicals adhering to the steel surface were linked to increased corrosion inhibition. The study's findings demonstrated that M. acuminata peduncle juice is a promising biomaterial for mild steel corrosion inhibitors in a salty environment.
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This paper introduces a unique and novel method for synthesizing thienyl chalcones using iron oxide nanoparticles (FeONPs) as a heterogeneous catalyst. It stands out as a rare example in the literature for the synthesis of these chalcones from 1,3-diketones and various aromatic aldehydes. The magnetic FeONPs employed as the catalyst bring several advantages, including their efficiency, affordability, and ecofriendly nature, making them an attractive choice for producing thiophene chalcones. One noteworthy aspect of this methodology is the utilization of mild reaction conditions, which greatly simplify the operational aspects of the reaction. Synthesized chalcones were confirmed through the application of various techniques, proton-NMR, 13C NMR, mass spectrometry, and single-crystal X-ray diffraction analysis. These analyses provide valuable insights into the chemical compositions and structural characteristics of the synthesized compounds. Significantly, this methodology is reported for the first time in the literature, indicating its novelty and contribution to the field of chalcone synthesis.
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The current work aims to synthesize new amphipathic compounds, TGHA and PGHA, and investigate their demulsification performance (DP) in water-in-crude oil emulsions. Their chemical structures, thermal stability, interfacial activity, and micelle formation were investigated by different techniques. The bottle test method was used to investigate the effect of demulsifier concentration, water content, temperature, and demulsification time (DT) on the DP of TGHA and PGHA compared to a commercial demulsifier (CD). The results indicated that these parameters have a noticeable impact on the DP of TGHA and PGHA. The results also showed that TGHA exhibited higher DP than PGHA at all investigated parameters, which could be explained by increasing its hydrophobicity due to lower oxyethylene units in its structure than PGHA. An increase in these units means increased hydrophilicity, which led to obstruction of PGHA molecule diffusion in crude oil as a continuous phase. Moreover, TGHA gave a comparable DP with CD, as it gave a higher DP and shorter DT than CD at a higher water content (50%), while the latter achieved the highest DP and the shortest DT at a low water content (10%).
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Supercapacitors (SCs) have emerged as attractive energy storage devices due to their rapid charge/discharge rates, long cycle life, and high-power density. However, the development of innovative electrode materials to achieve high-performance remains crucial to meet future requirements in supercapacitor technology. In this work, we have explored the potential of a microwave-engineered NiZrO3@GNP composite as a promising electrode material for SCs. A microwave assisted hydrothermal approach was adopted for the fabrication of the NiZrO3@GNP nanocomposite. Structural and morphological investigations showed its structural richness and its chemical compositions. When applied as a SC electrode, this innovative combination exhibits battery-like behaviour with higher specific capacity (577.63 C g-1) with good cyclic stability, and good performance. We have assembled an asymmetric-type two-electrode SC device and analysed its electrochemical features. This NiZrO3@GNP device exhibits the specific capacity of 47 C g-1 with capacitance retention of 70% after 2000 charge-discharge cycles. Further research on optimizing the synthesis process and exploring different device configurations could pave the way for even higher-performance supercapacitors in the future.
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The aim of this study involves the synthesis novel thiophene analogues that can be used as anticancer medications through a strategic multicomponent reaction connecting ethyl 4-chloroacetoacetate (1), phenyl isothiocyanate, and a series of active methylene reagents, including ethyl acetoacetate (2), malononitrile, ethyl cyanoacetate, cyanoacetamide 6a-c, N-phenyl cyanoacetamide derivatives 13a-c, and acetoacetanilide derivatives 18. This reaction was facilitated by dry dimethylformamide with a catalytic quantity of K2CO3. The resultant thiophene derivatives were identified as 4, 8a-b, 9, 12a-d, 15a-c, and 20a-b. Further reaction of compound 4 with hydrazine hydrate yielded derivative 5, respectively. When compound 1 was refluxed with ethyl 3-mercapto-3-(phenylamino)-2-(p-substituted phenyldiazenyl)acrylate 10a-e in the presence of sodium ethoxide, it produced thiophene derivatives 12a-d. Comprehensive structural elucidation of these newly synthesized thiophene-analogues was accomplished via elemental and spectral analysis data. Furthermore, the study delves into the cytotoxicity of the newly synthesized thiophenes was evaluated using the HepG2, A2780, and A2780CP cell lines. The amino-thiophene derivative 15b exhibited an increased growth inhibition of A2780, and A2780CP with IC50 values 12±0.17, and 10±0.15â µM, respectively compared to Sorafenib with IC50 values 7.5±0.54 and 9.4±0.14. This research opens new avenues for developing thiophene-based anticancer agents.
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Antineoplásicos , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Tiofenos , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Estrutura Molecular , Relação Estrutura-Atividade , Tiofenos/química , Tiofenos/farmacologia , Tiofenos/síntese químicaRESUMO
Photocatalysts have developed into a successful strategy for degrading synthetic and organic toxins, such as chemicals and dyes, in wastewater. In this study, graphene oxide was reduced at different temperatures and used for degrading indigo carmine and neutral red dyes. The wide surface areas, strong adsorption sites, and oxygen functionalities of reduced graphene oxide (rGO) at 250 °C (rGO-250) produced more photocatalytic degradation efficiency and adsorption percentage. The catalyst dosage, initial dye concentration, solution pH and recyclability were all used to optimize the photocatalytic activity of rGO-250. This research presents a capable nano-adsorbent photocatalyst for the efficient degradation of organic dyes. GO and rGOs were also investigated for carbon dioxide (CO2) absorption properties. Results showed that rGO-250 has better CO2 adsorption properties than other rGOs. Overall, it was observed that rGO-250 has better photocatalytic and CO2 adsorption capabilities compared to graphene oxide reduced at different temperatures.
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The present study involved the synthesis of La2YCrO6 double perovskites using a sol-gel approach. Additionally, a sonication method was implemented to prepare La2YCrO6 double perovskites decorated on halloysites (La2YCrO6/HLNTs). The La2YCrO6/HLNTs exhibited remarkable conductivity, electrocatalytic activity, and rapid electron transfer. It is imperative to possess these characteristics when overseeing the concurrent identification of Allura red (AR) and acid blue 9 (AB) in food samples. The development of the La2YCrO6/HLNTs was verified through the utilization of diverse approaches for structural and morphological characterization. The electrochemical techniques were employed to evaluate the analytical techniques of La2YCrO6/HLNTs. Impressively, the La2YCrO6/HLNTs demonstrated exceptional sensitivity, yielding the lowest detection limit for AR at 8.99 nM and AB at 5.14 nM. Additionally, the linear concentration range was 10-120 nM (AR and AB). The sensor that was developed exhibited remarkable selectivity, and the feasibility of AR and AB in the food sample was effectively monitored, resulting in satisfactory recoveries.
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In this study, the preparation of Sm2CuZrO6 double perovskites was carried out through the utilization of a sol-gel technique. The Sm2CuZrO6 displayed notable conductivity, impressive electrocatalytic activity, and rapid electron transfer. The monitoring of risperidone (RIS) in tablet samples is greatly influenced by these properties. Various techniques for structural and morphological characterization were employed to confirm the formation of Sm2CuZrO6. The electrochemical properties of Sm2CuZrO6 were assessed through utilization of cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and linear sweep voltammetry (LSV). Interestingly, the Sm2CuZrO6 exhibited a remarkable wide linear range of 50-500 nM, along with a detection limit of 10.62 nM. Notably, it demonstrated a sensitivity of 0.4038 µA µM-1 cm-2. The constructed sensor demonstrated noteworthy selectivity, stability, and repeatability. To assess the practicality of RIS, its performance was monitored in the tablet sample, resulting in satisfactory recoveries.
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Background and Objectives: Cancer is the second-most-important deadly disease in the world, leading to severe socioeconomic consequences and posing a public threat. Consequently, breast and colorectal cancers are significant cancer types that affect women and men more commonly, respectively. Treatment failure or recurrent diseases frequently occur due to resistance, in addition to the side effects of the currently available anticancer agents. Therefore, in this study, herbal melanin anticancer activity was investigated against human breast adenocarcinoma (MDA-MB-231) and human colorectal (HCT 116) cell proliferation and the expression of downregulated anti-apoptotic proteins and upregulated pro-apoptotic p53. Materials and Methods: MDA-MB-231 and HCT 116 cells were monitored for their real-time proliferation properties using Xcelligence. Herbal melanin of various concentrations significantly inhibited MDA-MB-231 and HCT 116 cell proliferation. Then, the expression of proapoptotic and anti-apoptotic proteins such as p53, Bcl-2 and Bcl-xl was studied using Western blotting. Results: The Bcl-2 and Bcl-xl expressions were downregulated, while the p53 expression was upregulated after treatment with herbal melanin. Similarly, the expression of apoptotic proteins such as Bcl-2, Bcl-xl, XIAP, Survivin, Bid, Bax, p53, Cytochrome C, PARP genes and mRNA was studied after herbal melanin treatment using real-time PCR, which revealed the downregulation of Bcl-2, Bcl-xl, XIAP and Survivin and the upregulation of Bid, Bax, p53, Cytochrome C and PARP apoptotic protein expression. Also, caspase 3 and 9 expressions were monitored after the treatment with herbal melanin, which revealed the upregulation of both the MDA-MB-231 and HCT 116 cell types. Conclusions: Overall, herbal melanin can be used as an alternative anticancer agent against the MDA-MB-231 and HCT 116 cell types.
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Antineoplásicos , Neoplasias da Mama , Feminino , Humanos , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Reguladoras de Apoptose/farmacologia , Proteínas Reguladoras de Apoptose/uso terapêutico , Células HCT116 , Proteína Supressora de Tumor p53/genética , Survivina/metabolismo , Survivina/farmacologia , Survivina/uso terapêutico , Melaninas/metabolismo , Melaninas/farmacologia , Melaninas/uso terapêutico , Apoptose , Proteína X Associada a bcl-2/genética , Citocromos c/metabolismo , Citocromos c/farmacologia , Citocromos c/uso terapêutico , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proliferação de Células , Antineoplásicos/uso terapêutico , Neoplasias da Mama/genética , Linhagem Celular TumoralRESUMO
This work deals with poly(ethylene terephthalate) waste as a precursor to synthesize new cross-linked poly(ionic liquids) (CLPILs). The newly synthesized CLPILs, VPCT-Cl and VPCT-AA, were used for magnetite nanoparticle surface modification, producing VCL/Fe3O4 and VAA/Fe3O4, respectively. The chemical structures of the CLPILs and surface-modified Fe3O4 were elucidated by Fourier transform infrared and X-ray diffraction. Additionally, the particle size, zeta potential (ζ), contact angle, and magnetic properties of VCL/Fe3O4 and VAA/Fe3O4 were investigated using different techniques. Furthermore, the performance of these nanoparticles for oil spill cleanup was evaluated using various influencing factors, e.g., the contact time and the Fe3O4/crude oil ratio. VCL/Fe3O4 and VAA/Fe3O4 showed excellent performance in oil spill cleanup. The data showed that the performance increased with the contact time and the Fe3O4 ratio. Furthermore, the reusability of VCL/Fe3O4 and VAA/Fe3O4 over four cycles was also explored. The reusability data indicated that reused VCL/Fe3O4 and VAA/Fe3O4 showed promising performance in oil spill cleanup.
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The coexistence of ceftazidime, which is a popular third-generation of cephalosporin antibiotic, with ubiquitous paracetamol or acetaminophen, is very likely because the latter is given to the patients to reduce fever due to bacterial infection along with an antibiotic such as the former. Therefore, in this study, we investigated the detailed binding of ceftazidime with plasma protein, human serum albumin (HSA), in the absence and presence of paracetamol using spectroscopic techniques such as fluorescence, UV-visible, and circular dichroism, along with in silico methods such as molecular docking, molecular dynamics simulations, and MM/PBSA-based binding free energy analysis. The basic idea of the interaction was attained by using UV-visible spectroscopy. Further, fluorescence spectroscopy revealed that there was a fair interaction between ceftazidime and HSA, and the mechanism of the quenching was a dynamic one, i.e., the quenching constant increased with increasing temperature. The interaction was, primarily, reinforced by hydrophobic forces, which resulted in the partial unfolding of the protein. Low concentrations of paracetamol were ineffective in affecting the binding of ceftazidime with has; although, a decrease in the quenching and binding constants was observed in the presence of high concentrations of the former. Competitive binding site experiments using warfarin and ibuprofen as site markers revealed that ceftazidime neither binds at drug site 1 or at drug site 2, articulating another binding site, which was confirmed by molecular docking simulations.
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Acetaminofen , Ceftazidima , Humanos , Ceftazidima/farmacologia , Simulação de Acoplamento Molecular , Ligação Proteica , Acetaminofen/farmacologia , Termodinâmica , Antibacterianos/farmacologia , Antibacterianos/química , Sítios de Ligação , Albumina Sérica Humana/química , Espectrometria de Fluorescência , Dicroísmo Circular , Anti-Inflamatórios não EsteroidesRESUMO
This work aims at synthesizing new cross-linked poly ionic liquids, CPILs, VIMDE-Cl and CPIL, VIMDE-TFA, utilizing polyethylene terephthalate waste as a precursor and applying them to magnetite nanoparticles surface modification, producing surface-modified magnetite nanoparticles, SMNPs, VDCL/MNPs, and VDTA/MNPs, respectively. The structures of VIMDE-Cl and VIMDE-TFA, VDCL/MNPs, and VDTA/MNPs, were verified using different techniques. The particle sizes of SMNPs, VDCL/MNPs, and VDTA/MNPs, were evaluated with a transmission electron microscope and dynamic light scattering. The compatibility of VDCL/MNPs and VDTA/MNPs with crude oil components and their response to an external magnet were also measured using contact angle measurements and a vibrating sample magnetometer. The data confirmed the formation of SMNPs, nanosized structure, compatibility with oil components, and response to an external magnet. For that, VDCL/MNPs and VDTA/MNPs were applied for oil spill recovery using different SMNP : crude oil weight ratios. The impact of contact time on SMNPs' performance was also evaluated. The data indicated increased performance with an increase in SMNPs ratio, reaching maximum values of 99% and 96% for VDCL/MNPs and VDTA/MNPs, respectively, at SMNPs : crude oil ratio of 1 : 1. According to the results, the optimal contact time was 6 min, resulting in 89% and 97% performance for VDCL/MNPs and VDTA/MNPs at 1 : 4 SMNPs : crude oil ratio.