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1.
Int J Biol Macromol ; 274(Pt 2): 133442, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38936578

RESUMO

A potential bio-adsorbent material for removing Rhodamine B (RB) from aqueous solution is Ru-MOF@FGA/CA beads. The adsorption capability of the material is probably enhanced by the use of a natural substance made of food-grade algae (FGA) and calcium alginate (CA), which has been cross-linked and loaded with ruthenium metal-organic frameworks (Ru-MOF). The Ru-MOF@FGA/CA beads were analyzed by XPS, PXRD, FT-IR, and SEM. The nitrogen adsorption-desorption isotherm analysis of the Ru-MOF@FGA/CA beads before and after the adsorption of RB revealed that had a surface area of 682 m2/g, a pore size of 2.92 nm, and a pore volume of 1.62 cc/g, that decreased after adsorption as the surface area reduced to 468.62 m2/g, while the pore volume reduced to 0.76 cc/g. indicating that the RB molecules occupied the available space within the pores of the material. The decrease in both surface area and pore volume specifies that the Ru-MOF@FGA/CA beads' pores were able to effectively adsorb the RB molecules. The adsorption of RB against the Ru-MOF@FGA/CA beads is affected by pH, adsorbent dose, starting RB concentration, and salinity. Controlling these factors can enhance the adsorption capability and effectiveness of the beads for RB removal. With an adsorption energy of 22.6 kJ/mol, the adsorption of RB onto the Ru-MOF@FGA/CA beads was determined to be a chemisorption process, demonstrating a strong bond among the adsorbent and the adsorbate. The pseudo-second-order kinetics and Langmuir isotherms were used to suit the adsorption process. Because the adsorption procedure was endothermic, it increased as the temperature increased. By using this information, the adsorption conditions may be improved, and the beads' ability to absorb RB can be increased. Up to six reuses of the Ru-MOF@FGA/CA beads are possible without affecting their chemical makeup and maintaining analogous PXRD and FT-IR data after each reuse. The adsorption process can be optimized through the application of the Box-Behnken design (BBD) approach and may entail H-bonding, electrostatic forces, n-π stacking, and pore filling. The exceptional stability of the beads makes them useful for creating long-lasting and efficient adsorbents that remove contaminants from water.


Assuntos
Alginatos , Estruturas Metalorgânicas , Termodinâmica , Poluentes Químicos da Água , Alginatos/química , Adsorção , Cinética , Poluentes Químicos da Água/química , Estruturas Metalorgânicas/química , Purificação da Água/métodos , Concentração de Íons de Hidrogênio , Corantes/química , Água/química , Rodaminas/química , Rutênio/química
2.
Int J Biol Macromol ; 268(Pt 2): 131947, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38685542

RESUMO

Trimethoprim (TMP), an antibiotic contaminant, can be effectively removed from water by using the innovative magnetic metal-organic framework (MOF) composite sponge Fe3O4@Rh-MOF@PIC, which is shown in this study. The composite is made up of magnetite (Fe3O4) nanoparticles and a rhodium MOF embedded in a poly(itaconic acid) grafted chitosan matrix. The structure and characteristics of the synthesized material were confirmed by thorough characterization employing SEM, FTIR, XPS, XRD, and BET techniques. Notably, the composite shows a high magnetic saturation of 64 emu g-1, which makes magnetic separation easier, according to vibrating sample magnetometry. Moreover, BET analysis revealed that the Fe3O4@Rh-MOF@PIC sponge had an incredibly high surface area of 1236.48 m2/g. Its outstanding efficacy was confirmed by batch adsorption tests, which produced a maximum adsorption capacity of 391.9 mg/g for the elimination of TMP. Due to its high porosity, magnetic characteristics, and superior trimethoprim uptake, this magnetic MOF composite sponge is a promising adsorbent for effective removal of antibiotics from contaminated water sources. An adsorption energy of 24.5 kJ/mol was found by batch investigations on the Fe3O4@Rh-MOF@PIC composite sponge for trimethoprim (TMP) adsorption. The fact that this value was up 8 kJ/mol suggests that the main mechanism controlling TMP absorption onto the sponge adsorbent is chemisorption. Chemisorption requires creating strong chemical interactions between adsorbate and adsorbent surface groups, unlike weaker physisorption. The magnetic composite sponge exhibited strong removal capabilities and high adsorption capacities for the antibiotic pollutant. The Fe3O4@Rh-MOF@PIC composite sponge also showed magnetism, which allowed for easy magnetic separation after adsorption. Over the course of 6 cycles, it showed outstanding reusability, and XRD confirmed that its composition was stable. The high surface area MOF's pore filling, hydrogen bonding, π-π stacking, and electrostatic interactions were the main trimethoprim adsorption mechanisms. This magnetic composite is feasible and effective for removing antibiotics from water because of its separability, reusability, and synergistic adsorption mechanisms via electrostatics, H-bonding, and π-interactions. The adsorption results were optimized using Box Behnken-design (BBD).


Assuntos
Quitosana , Estruturas Metalorgânicas , Trimetoprima , Águas Residuárias , Poluentes Químicos da Água , Purificação da Água , Quitosana/química , Estruturas Metalorgânicas/química , Trimetoprima/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Purificação da Água/métodos , Águas Residuárias/química , Termodinâmica , Cinética , Succinatos
3.
Int J Biol Macromol ; 263(Pt 1): 130255, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38368988

RESUMO

Developing an efficient adsorbent for Ru3+ ions in wastewater is crucial for both environmental protection and resource recovery. This study introduces a novel approach using cellulose-based adsorbents, specifically modified with furan-thiosemicarbazide (FTC), to enhance their selectivity for Ru3+ ions. By cross-linking the Ru3+/FTC-modified cellulose (FTC-CE) complex with a bis(maleimido)ethane (BME) cross-linker, we created a Ru3+ ion-imprinted sorbent (Ru-II-CE) that exhibits a strong affinity and selectivity for Ru3+ ions. The synthesis process was thoroughly characterized using NMR and FTIR spectroscopy, while the surface morphology of the sorbent particles was examined with scanning electron microscopy. The Ru-II-CE sorbent demonstrated exceptional selectivity for Ru3+ among competing metal cations, achieving optimal adsorption at a pH of 5. Its adsorption capacity was notably high at 215 mg/g, fitting well with the Langmuir isotherm model, and it followed pseudo-second-order kinetics. This study highlights the potential of FTC-CE for targeted Ru3+ removal from wastewater, offering a promising solution for heavy metal decontamination.


Assuntos
Rutênio , Semicarbazidas , Poluentes Químicos da Água , Águas Residuárias , Celulose/química , Íons , Adsorção , Concentração de Íons de Hidrogênio , Poluentes Químicos da Água/química , Cinética
4.
Molecules ; 28(6)2023 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-36985526

RESUMO

A new class of biologically active mineral complexes was synthesized by reacting the following metal salts: MnCl2·4H2O, CoCl2·6H2O, CuCl2·2H2O, CrCl3·6H2O, and PdCl2 respectively with 2-amino-4,6-dimethyl pyrimidine (ADMPY) and Schiff's base resulting from the condensation reaction between benzaldehyde with p-phenylenediamine and 2-hydroxy-1-naphthaldehyde as ligands have been synthesized and characterized on the basis of their CHN, thermal analysis, XRD, SEM and magnetic measurements along with their FT-IR and UV-vis spectra. The scanning electron microscope SEM measurements and the calculations on the powder XRD data indicate the nano-sized nature of the prepared complexes (average size 32-88 nm). The spectral data confirmed the coordinated ligand (HL) via a nitrogen atom of an azomethine group (-C=N-) and phenolic -OH group and NH2-ADMPY ligand with the metal ions. An octahedral geometry for all complexes has been proposed based on magnetic and electronic spectral data except Pd(II) complex, which has a tetrahedral geometry. Molecular modeling was performed for Cu(II) complex using the density functional method DFT/B3LYP to study the structures and the frontier molecular orbitals (HOMO and LUMO). The antioxidant of the complexes was studied using the 2,2-diphenyl-1-picrylhydrazyl (DPPH)-free radical-scavenging assays. The metal complexes were tested in vitro for anticancer activities against two cancer lines A-549 and MRC-5 cells. Cu(II) and Pd(II) complexes showed the highest cytotoxicity effect, comparable to that of other cis-platinum-based drugs. The complexes showed significant activity against fungi and bacteria.


Assuntos
Anti-Infecciosos , Complexos de Coordenação , Antioxidantes/farmacologia , Antioxidantes/química , Espectroscopia de Infravermelho com Transformada de Fourier , Ligantes , Cobre/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Metais/química , Bases de Schiff/farmacologia , Bases de Schiff/química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Testes de Sensibilidade Microbiana
5.
Carbohydr Polym ; 308: 120596, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36813349

RESUMO

Ion-imprinting technique was used to create a lead ion-imprinted sorbent from an amino-thiol chitosan derivative (Pb-ATCS). First, 3-Nitro-4-sulfanylbenzoic acid (NSB) unit's amidized the chitosan, and then the -NO2-residues were selectively reduced to -NH2. Imprinting was accomplished by cross-linking with epichlorohydrin and removing the Pb (II) ions from the across-linked polymeric complex formed from the amino-thiol chitosan polymer ligand (ATCS) and Pb (II) ions. The synthetic steps have been investigated by nuclear magnetic resonance (NMR) and Fourier transform infrared spectroscopy (FTIR), and the sorbent was tested for its ability to selectively bind Pb (II) ions. The produced Pb-ATCS sorbent had a maximum capacity of roughly 300 mg/g, and it showed a greater affinity for the Pb (II) ions than the control NI-ATCS sorbent particle. The pseudo-2nd-order equation was also consistent with the adsorption kinetics of the sorbent, which were quite rapid. This demonstrated that metal ions were chemo-adsorbed onto the Pb-ATCS and NI-ATCS solid surfaces via coordination with the introduced amino-thiol moieties.

6.
Luminescence ; 38(3): 350-359, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36775810

RESUMO

Recently, various studies have focused on the development of multifunctional non-woven polyethylene terephthalate (PT; polyester) textiles. Herein, we introduce multifunctional non-woven polyester fabrics by pad dry curing silver nitrate (AgNO3 ) and aniline monomer into plasma-pretreated non-woven PT textile. This creates a nanocomposite layer of silver nanoparticles (AgNPs) and polyaniline (PANi) on the fabric surface. In order to prepare a non-woven fibrous mat, we applied the melt-spinning technique on previously shredded recycled PT plastic waste. On the surface of the cloth, PANi was synthesized by REDOX polymerization of aniline. Due to the oxidative polymerization, the silver ions (Ag+ ) were converted to Ag0 NPs. PANi acted as a conductor while AgNPs inhibited the growth of microorganisms. Microwave-assisted curing with trimethoxyhexadecylsilane (TMHDS) gave PT textiles with superhydrophobic properties. The morphological studies were performed using Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDX). The stiffness and breathability of finished non-woven PT textile materials were analyzed to establish their comfort levels. Both of Escherichia coli and Staphylococcus aureus were used to test the efficacy of the AgNPs-treated textiles as antimicrobial materials. Moreover, the processed polyester textiles showed excellent electrical conductivity and great ultraviolet-ray blocking.


Assuntos
Nanopartículas Metálicas , Polietilenotereftalatos , Nanopartículas Metálicas/química , Prata , Têxteis , Compostos de Anilina , Antibacterianos/química
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