Cu,Ce-containing phosphotungstates as laccase-like nanozyme for colorimetric detection of Cr(VI) and Fe(â ¢).

Herein, a nanocomposite of Cu,Ce-containing phosphotungstates (Cu,Ce-PTs) with outstanding laccase-like activity was fabricated via a one-pot microwave-assisted hydrothermal method. Notably, it was discovered that both Fe3+ and Cr6+ could significantly enhance the electron transfer rates of Ce3+ and Ce4+, along with generous Cu2+ with high catalytic activity, thereby promoting the laccase-like activity of Cu,Ce-PTs. The proposed system can be used for the detection of Fe3+ and Cr6+ in a range of 0.667-333.33 µg/mL and 0.033-33.33 µg/mL with a low detection limit of 0.135 µg/mL and 0.0288 µg/mL, respectively. The proposed assay exhibits excellent reusability and selectivity and can be used in traditional Chinese medicine samples analysis.

Photoelectrochemical sensor for nitrite determination based on the etching of BiOCl/Zn0.5Cd0.5S.

A rapid photoelectrochemical (PEC) sensor was constructed for nitrite detection in food based on the one-step chemical etching strategy of BiOCl/Zn0.5Cd0.5S (BOC/ZCS) nanocomposites by nitrite. BOC/ZCS heterojunction was prepared by a simple coprecipitation method, and it was found that BOC/ZCS showed significant photoelectrochemical (PEC) activity. The results of this study confirmed that the decrease in the photocurrent of the sensor was linked to the etching of ZCS by nitrite under acidic conditions. Under optimized conditions, the BOC/ZCS-based PEC sensor showed good analytical properties for detecting nitrite, with linear ranges of 1-100 µM and 100-600 µM. The detection limit of the sensor was 0.41 µM (S/N = 3). Excellent repeatability, reproducibility, low background noise, and immunity to interference were demonstrated using the proposed system, and satisfactory results were achieved for the nitrite assay using real samples. These results demonstrate a new method for nitrite detection developed using the proposed PEC sensor.

Ti3C2 MXene/MoS2@AuNPs ternary nanocomposite for highly sensitive electrochemical detection of phoxim residues in fruits.

Phoxim, extensively utilized in agriculture as an organothiophosphate insecticide, has the potential to cause neurotoxicity and pose human health hazards. In this study, an electrochemical enzyme biosensor based on Ti3C2 MXene/MoS2@AuNPs/AChE was constructed for the sensitive detection of phoxim. The two-dimensional multilayer structure of Ti3C2 MXene provides a robust framework for MoS2, leading to an expansion of the specific surface area and effectively preventing re-stacking of Ti3C2 MXene. Additionally, the synergistic effect of self-reduced grown AuNPs with MoS2 further improves the electrical conductivity of the composites, while the robust framework provides a favorable microenvironment for immobilization of enzyme molecules. Ti3C2 MXene/MoS2@AuNPs electrochemical enzyme sensor showed a significant response to phoxim in the range of 1 × 10-13 M to 1 × 10-7 M with a detection limit of 5.29 × 10-15 M. Moreover, the sensor demonstrated excellent repeatability, reproducibility, and stability, thereby showing its promising potential for real sample detection.

A comparison increasing the photodegradation power of a Ag/g-C3N4 /CoNi-LDH nanocomposite: Photocatalytic activity toward water treatment.

For environmental applications, it is crucial to rationally design and synthesize photocatalysts with positive exciton splitting and interfacial charge transfer. Here, a novel Ag-bridged dual Z-scheme Ag/g-C3N4/CoNi-LDH plasmonic heterojunction was successfully synthesized using a simple method, with the goal of overcoming the common drawbacks of traditional photocatalysts such as weak photoresponsivity, rapid combination of photo-generated carriers, and unstable structure. These materials were characterized by XRD, FT-IR, SEM, TEM UV-Vis/DRS, and XPS to verify the structure and stability of the heterostructure. The pristine LDH, g-C3N4, and Ag/g-C3N4/CoNi-LDH composite were investigated as photocatalysts for water remediation, an environmentally motivated process. Specifically, the photocatalytic degradation of tetracycline was studied as a model reaction. The performance of the supports and composite catalyst were determined by evaluating both the degradation and adsorption phenomenon. The influence of several experimental parameters such as catalyst loading, pH, and tetracycline concentration were evaluated. The current study provides important data for water treatment and similar environmental protection applications.

Bioactive nanocomposite hydrogel enhances postoperative immunotherapy and bone reconstruction for osteosarcoma treatment.

Osteosarcoma, a malignant bone tumor often characterized by high hedgehog signaling activity, residual tumor cells, and substantial bone defects, poses significant challenges to both treatment response and postsurgical recovery. Here, we developed a nanocomposite hydrogel for the sustained co-delivery of bioactive magnesium ions, anti-PD-L1 antibody (αPD-L1), and hedgehog pathway antagonist vismodegib, to eradicate residual tumor cells while promoting bone regeneration post-surgery. In a mouse model of tibia osteosarcoma, this hydrogel-mediated combination therapy led to remarkable tumor growth inhibition and hence increased animal survival by enhancing the activity of tumor-suppressed CD8+ T cells. Meanwhile, the implanted hydrogel improved the microenvironment of osteogenesis through long-term sustained release of Mg2+, facilitating bone defect repair by upregulating the expression of osteogenic genes. After 21 days, the expression levels of ALP, COL1, RUNX2, and BGLAP in the Vis-αPD-L1-Gel group were approximately 4.1, 5.1, 5.5, and 3.4 times higher than those of the control, respectively. We believe that this hydrogel-based combination therapy offers a potentially valuable strategy for treating osteosarcoma and addressing the tumor-related complex bone diseases.

Green synthesis of novel Z-scheme SnS2/HAp nanocomposite using Ocimum tenuiflorum leaf extract and investigation of its photocatalytic activity.

The present study focuses on the green synthesis of a novel Z-scheme SnS2/HAp photocatalyst using Ocimum tenuiflorum (tulsi) leaf extract as a stabilizing agent. This approach not only emphasizes sustainability but also adds value to waste by extracting hydroxyapatite (HAp) from Labeo rohita fish scales, addressing the challenge of their disposal. The synthesized photocatalyst was thoroughly characterized using a range of analytical techniques to evaluate its crystal structure, optical properties, morphology, and elemental composition. The photocatalytic activity of the SnS2/HAp composite was assessed through the degradation of gentian violet (GV) dye, a representative organic pollutant. Various reaction parameters were optimized to enhance the degradation efficiency, and the photocatalyst's performance was further tested across different water matrices. Under optimal conditions, the SnS2/HAp photocatalyst achieved a maximum photodegradation efficiency of 97.49% with a rate constant of 0.0494 min- 1 for GV dye. Additionally, it exhibited an efficiency greater than 70% against other emerging pollutants via advanced oxidation processes (AOP). The enhanced photocatalytic activity was attributed to the formation of a Z-Scheme heterojunction between SnS2 and HAp, which enhanced the charge separation efficiency and delayed the charge recombination. The study also demonstrated the photocatalyst's remarkable reusability, maintaining high performance over five cycles and across various water environments. This highlights its potential as a sustainable solution for the removal of organic pollutants from aqueous streams. Finally, a Z-scheme electron transport mechanism is proposed to explain the photodegradation process of GV dye using the SnS2/HAp photocatalyst.

Two-dimensional black phosphorus/platinum catalase-like nanozyme-based Fenton reaction-mediated dual-mode immunoassays for the detection of enrofloxacin.

Hydrogen peroxide-based Fenton reaction can effectively degrade many small-molecule fluorescent dyes, leading to notable alterations in fluorescence signals. Additionally, the two-dimensional black phosphorus/platinum nanocomposite (BP/Pt) demonstrates exceptional catalase (CAT) characteristics. Based on these, a colorimetric-fluorescence dual-mode signal output pattern based on BP/Pt-Fenton reaction-rhodamine B tandem reaction system is reported. The physical adsorption property of the BP/Pt nanozymes was utilized to couple with antibodies, thus constructing a novel dual-mode nanozyme-based immuno-sensing assay (NISA). By using the migratory antibiotic enrofloxacin (ENR) as the target, the NISA provided highly sensitive detection with the detection limits of 0.058 ng/mL for colorimetric-mode and 0.025 ng/mL for fluorescence-mode and achieved accurate quantitative detection in environmental water and crucian carp samples. This work provides an innovative design for monitoring antibiotics in the environment and broadens the idea for the application of nanozymes and Fenton systems in immunosensing assays.

Concentration-Dependent Effects of MXene Nanocomposite-Loaded Carboxymethyl Cellulose on Wound Healing.

Nanoparticles (NPs) have emerged as a promising solution for many biomedical applications. Although not all particles have antimicrobial or regenerative properties, certain NPs show promise in enhancing wound healing by promoting tissue regeneration, reducing inflammation, and preventing infection. Integrating various NPs can further enhance these effects. Herein, the zinc oxide (ZnO)-MXene-Ag nanocomposite was prepared, and the conjugation of its three components was confirmed through scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) mapping analysis. In vitro analysis using the agar well diffusion technique demonstrated that ZnO-MXene-Ag nanocomposite exhibited high antimicrobial efficacy, significantly inhibiting Escherichia coli, Salmonella, and Candida albicans, and showing enhanced potency when combined with tetracycline, resulting in a 2.6-fold increase against Staphylococcus and a 2.4-fold increase against Pseudomonas. The efficacy of nanocomposite-loaded carboxymethyl cellulose (CMC) gel on wound healing was investigated using varying concentrations (0, 1, 5, and 10 mg/mL). Wound healing was monitored over 21 days, with results indicating that wounds treated with 1 mg/mL ZnO-MXene-Ag gel exhibited superior healing compared to the control group (0 mg/mL), with significant improvements noted from Day 3 onward. Conversely, higher concentrations (10 mg/mL) resulted in reduced healing efficiency, particularly notable on Day 15. In conclusion, the ZnO-MXene-Ag nanocomposite-loaded CMC gel is a promising agent for enhanced wound healing and antimicrobial applications. These findings highlight the importance of optimizing NP concentration to maximize therapeutic benefits while minimizing potential cytotoxicity.

Synergistic effects of thermally reduced graphene oxide/zinc oxide composite material on microbial infection for wound healing applications.

Infections originating from pathogenic microorganisms can significantly impede the natural wound-healing process. To address this obstacle, innovative bio-active nanomaterials have been developed to enhance antibacterial capabilities. This study focuses on the preparation of nanocomposites from thermally reduced graphene oxide and zinc oxide (TRGO/ZnO). The hydrothermal method was employed to synthesize these nanocomposites, and their physicochemical properties were comprehensively characterized using X-ray diffraction analysis (XRD), High-resolution transmission electron microscopy (HR-TEM), Fourier-transform infrared (FT-IR), Raman spectroscopy, UV-vis, and field-emission scanning electron microscopy (FE-SEM) techniques. Subsequently, the potential of TRGO/ZnO nanocomposites as bio-active materials against wound infection-causing bacteria, including Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli, was evaluated. Furthermore, the investigated samples show disrupted bacterial biofilm formation. A reactive oxygen species (ROS) assay was conducted to investigate the mechanism of nanocomposite inhibition against bacteria and for further in-vivo determination of antimicrobial activity. The MTT assay was performed to ensure the safety and biocompatibility of nanocomposite. The results suggest that TRGO/ZnO nanocomposites have the potential to serve as effective bio-active nanomaterials for combating pathogenic microorganisms present in wounds.

Novel nanocomposite and biochar insights to boost rice growth and alleviation of Cd toxicity.

Cadmium (Cd) is an unessential and pervasive contaminant in agricultural soil, eventually affecting the food and instigating health issues. The implication of nanocomposites in agriculture attained significant attention to drive food security. Nanocomposites possess exceptional characteristics to stun the challenges of chemical fertilizers that can enhance plant yield and better nutrient bioavailability. Similarly, biochar has the ability to immobilize Cd in soil by reducing mobility and bioavailability. Rice husk biochar is produced at high temperature pyrolysis under anoxic conditions and a stable carbon-rich material is formed. To strive against this issue, rice plants were subjected to Cd (15, 20 mg kg- 1) stress and treated with alone/combined Ca + Mg (25 mg L- 1) nanocomposite and rice husk biochar. In our study, growth and yield traits showed the nurturing influence of Ca + Mg nanocomposite and biochar to improve rice defence mechanism by reducing Cd stress. Growth parameters root length 28%, shoot length 34%, root fresh weight 19%, shoot fresh weight 16%, root dry weight 9%, shoot dry weight 8%, number of tillers 32%, number of grains 20%, and spike length 17% were improved with combined application of Ca + Mg and biochar, with Cd (20 mg kg- 1), rivalled to alone biochar. Combined Ca + Mg and biochar application increased the SPAD 23%, total chlorophyll 26%, a 19%, b 18%, and carotenoids 15%, with Cd (20 mg kg- 1), rivalled to alone biochar. MDA 15%, H2O2 13%, and EL 10% were significantly regulated in shoots with combined Ca + Mg and biochar application with Cd (20 mg kg- 1) compared to alone biochar. POD 22%, SOD 17%, APX 18%, and CAT 9% were increased in shoots with combined Ca + Mg and biochar application with Cd (20 mg kg- 1) compared to alone biochar. Cd uptake in roots 13%, shoots 14%, and grains 21% were minimized under Cd (20 mg kg- 1) with combined Ca + Mg and B. pumilus application, compared to alone biochar. Subsequently, combined Ca + Mg and biochar application is a sustainable solution to boost crop production under Cd stress.

Oral delivery of Sunitinib malate using carboxymethyl cellulose/poly(acrylic acid-itaconic acid)/Cloisite 30B nanocomposite hydrogel as a pH-responsive carrier.

This work aimed to fabricate a Cloisite 30B-incorporated carboxymethyl cellulose graft copolymer of acrylic acid and itaconic acid hydrogel (Hyd) via a free radical polymerization method for controlled release of Sunitinib malate anticancer drug. The synthesized samples were characterized by FTIR, XRD, TEM, and SEM-dot mapping analyses. The encapsulation efficiency of Hyd and Hyd/Cloisite 30B (6 wt%) was 81 and 93%, respectively, showing the effectiveness of Cloisite 30B in drug loading. An in vitro drug release study showed that drug release from all samples in a buffer solution with pH 7.4 was higher than in a buffer solution with pH 5.5. During 240 min, the cumulative drug release from Hyd/Cloisite 30B (94.97% at pH 7.4) is lower than Hyd (53.71% at pH 7.4). Also, drug-loaded Hyd/Cloisite 30B (6 wt%) demonstrated better antibacterial activity towards S. Aureus bacteria and E. Coli. High anticancer activity of Hyd/Cloisite 30B against MCF-7 human breast cancer cells was shown by the MTT assay, with a MCF-7 cell viability of 23.82 ± 1.23% after 72-hour incubation. Our results suggest that Hyd/Cloisite 30B could be used as a pH-controlled carrier to deliver anticancer Sunitinib malate.

Nanocomposites: silver nanoparticles and bacteriocins obtained from lactic acid bacteria against multidrug-resistant Escherichia coli and Staphylococcus aureus.

Drug-resistant bacteria such as Escherichia coli and Staphylococcus aureus represent a global health problem that requires priority attention. Due to the current situation, there is an urgent need to develop new, more effective and safe antimicrobial agents. Biotechnological approaches can provide a possible alternative control through the production of new generation antimicrobial agents, such as silver nanoparticles (AgNPs) and bacteriocins. AgNPs stand out for their antimicrobial potential by employing several mechanisms of action that can act simultaneously on the target cell such as the production of reactive oxygen species and cell wall rupture. On the other hand, bacteriocins are natural peptides synthesized ribosomally that have antimicrobial activity and are produced, among others, by lactic acid bacteria (LAB), whose main mechanism of action is to produce pores at the level of the cell membrane of bacterial cells. However, these agents have disadvantages. Nanoparticles also have limitations such as the tendency to form aggregates, which decreases their antibacterial activity and possible cytotoxic effects, and bacteriocins have a narrow spectrum of action, require high doses to be effective, and can be degraded by proteases. Given these limitations, nanoconjugates of these two agents have been developed that can act synergistically in the control of pathogenic bacteria resistant to antibiotics. This review focuses on knowing relevant aspects of the antibiotic resistance of E. coli and S. aureus, the characteristics of these new generation antibacterial agents, and their effect alone or forming nanoconjugates that are more effective against the multiresistant mentioned bacteria.

Integrated triple signal amplification strategy for ultrasensitive electrochemical detection of gastric cancer-related microRNA utilizing MoS2-based nanozyme, hybridization chain reaction, and horseradish peroxidase.

Early diagnosis and treatment of gastric cancer (GC) play a vital role in improving efficacy, reducing mortality and prolonging patients' lives. Given the importance of early detection of gastric cancer, an electrochemical biosensor was developed for the ultrasensitive detection of miR-19b-3p by integrating MoS2-based nanozymes, hybridization chain reaction (HCR) with enzyme catalyzed reaction. The as-prepared MoS2-based nanocomposites were used as substrate materials to construct nanoprobes, which can simultaneously load probe DNA and HCR initiator for signal amplification. Moreover, the MoS2-based nanocomposites are also employed as nanozymes to amplify electrochemical response. The presence of miR-19b-3p induced the assembly of MoS2-based nanoprobes on the electrode surface, which can activate in-situ HCR reaction to load a large number of horseradish peroxidase (HRP) for signal amplification. Coupling with the co-catalytic ability of HRP and MoS2-based nanozymes, the designed electrochemical biosensor can detect as low as 0.7 aM miR-19b-3p. More importantly, this biosensor can efficiently analyze miR-19b-3p in clinical samples from healthy people and gastric cancer patients due to its excellent sensitivity and selectivity, suggesting that this biosensor has a potential application in early diagnosis of disease.

Poly(ε-Caprolactone)-Based Composites Modified With Polymer-Grafted Magnetic Nanoparticles and L-Ascorbic Acid for Bone Tissue Engineering.

The aim of this study was to develop multifunctional magnetic poly(ε-caprolactone) (PCL) mats with antibacterial properties for bone tissue engineering and osteosarcoma prevention. To provide good dispersion of magnetic iron oxide nanoparticles (IONs), they were first grafted with PCL using a novel three-step approach. Then, a series of PCL-based mats containing a fixed amount of ION@PCL particles and an increasing content of ascorbic acid (AA) was prepared by electrospinning. AA is known for increasing osteoblast activity and suppressing osteosarcoma cells. Composites were characterized in terms of morphology, mechanical properties, hydrolytic stability, antibacterial performance, and biocompatibility. AA affected both the fiber diameter and the mechanical properties of the nanocomposites. All produced mats were nontoxic to rat bone marrow-derived mesenchymal cells; however, a composite with 5 wt.% of AA suppressed the initial proliferation of SAOS-2 osteoblast-like cells. Moreover, AA improved antibacterial properties against Staphylococcus aureus and Escherichia coli compared to PCL. Overall, these magnetic composites, reported for the very first time, can be used as scaffolds for both tissue regeneration and osteosarcoma prevention.

Platinum-perovskite nanocomposite-based Exosensor for specific detection of prostate cancer in clinical settings.

Exosomes, extracellular vesicles (EVs) with an average size of 50-150 nm, transfer various biomolecules and exchange signaling molecules between cells in a paracrine manner. Molecular investigations have revealed that EVs can reflect real-time metabolic changes in normal- and cancer-origin cells and thus harbor valid diagnostic biomarkers. Despite these advantages, the detection of low concentrations of cancer cell EVs in biological fluids is still a great challenge. Here, a new electrochemical Exosensor based on platinum-perovskite is developed for the direct detection of EVs using a biotinylated monoclonal CD63 antibody as a capture element. The label-free method exhibited higher sensitivity with a lower limit of quantification of 2000 EVs/µL with a dynamic linear range (LDR) of 2000 to 14,000 EVs/µL compared with other available methods. To enhance the selectivity of detection, EVs were simultaneously sandwiched between secondary antibodies of PSA (prostate-specific antigen), as an FDA-approved prostate cancer biomarker. Data indicated that this Exosensor can distinguish normal and cancer EVs in samples from healthy individuals and prostate cancer patients. Taken together, this technology offers a unique approach to label-free quantification of EVs and cancer detection in the early stages.

Signal-enhanced electrochemical sensor employing MWCNTs/CMK-3/AuNPs and Au@Pd core-shell structure for sensitive determination of AFB1 in complex matrix.

A sandwich electrochemical sensor was fabricated based on multi-walled carbon nanotubes/ordered mesoporous carbon/AuNP (MWCNTs/CMK-3/AuNP) nanocomposites and porous core-shell nanoparticles Au@PdNPs to achieve rapid and sensitive detection of AFB1 in complex matrices. MWCNTs/CMK-3/AuNP nanocomposite, which was prepared by self-assembly method, served as a substrate material to increase the aptamer loading and improve the conductivity and electrocatalytic activity of the electrode for the first signal amplification. Then, Au@PdNPs, which were synthesized by one-pot aqueous phase method, were applied as nanocarriers loaded with plenty of capture probe antibody (Ab) and signal molecule toluidine blue (Tb) to form the Au@PdNPs-Ab-Tb bioconjugates for secondary signal amplification. The sensing system could still significantly improve the signal output intensity even in the presence of ultra-low concentration target compound due to the dual signal amplification of MWCNTs/CMK-3/AuNP nanocomposites and Au@PdNPs-Ab-Tb. The method exhibited high selectivity, low detection limit (9.13 fg/mL), and strong stability to differentiate AFB1 from other mycotoxins. Furthermore, the sensor has been successfully applied to the quantitative determination of AFB1 in corn, malt, and six herbs, which has potential applications in food safety, quality control, and environmental monitoring.

Evaluation of Colour Changes in Nanocomposite-Based Bulk-Fill and Universal Composite Using Different Polishing Systems.

PURPOSE: Resins composites are widely used in modern dentistry because of their aesthetic and physical properties. However, discoloration of anterior tooth restorations is a common complaint. Understanding the factors affecting the colour stability of resin composites can lead to longer-lasting repairs. This study aimed to evaluate and compare the colour changes of nanocomposite-based bulk-fill and universal resin composites after immersion in coffee using various polishing systems. MATERIALS AND METHODS: A total of 160 samples were prepared using four different composite groups, with 40 pieces for each combined group. Based on the finishing procedure, the samples were divided into four subgroups for each composite group. Three different polishing procedures were applied to the samples according to the manufacturer's instructions. The control group was not subjected to any treatment. Initial colour measurements were performed using a VITA Easyshade V spectrophotometer. After the initial measurements, the samples were immersed in a Nescafe coffee solution for seven days, followed by colour measurements. Data were analysed using the Kolmogorov-Smirnov test and two-way analysis of variance. Tukey's honest significant difference (HSD) test was used to determine differences between subgroups. RESULTS: The results indicate that bulk-fill resins exhibit more discolouration than universal composites; however, this difference was not statistically significant. The resin group with the smallest discolouration was Ceram X, and the most effective polishing method was Twist polishing. CONCLUSION: Final surface polishing significantly reduced the composites' discolouration. These findings support the selection of appropriate materials and polishing techniques to achieve aesthetic outcomes and colour stability in dental restorations.

Fabrication of a green double-layered hybrid nanocomposite via electrospinning of polyethersulphone/natural deep eutectic solvent on bacterial cellulose for determination of multiclass pesticides in water samples.

A novel nanofibrous double-layered biosorbent was fabricated by electrospinning polyethersulfone (PES) doped with a natural deep eutectic solvent (DES), composed of choline chloride (ChCl) and caffeic acid (CFA) in a 3:1 molar ratio, onto a bacterial cellulose (BC) substrate. The pristine PES/DES@BC biosorbent was employed in a thin film-solid phase microextraction (TF-SPME) to extract 12 multiclass pesticides from water. Characterization techniques, including ATR-FTIR, FT-NMR, SEM, and nitrogen adsorption/desorption isotherms, confirmed the nanofibrous structure of the electrospun PES-DES and BC biopolymer. The method was validated for matrix effect, specificity, reproducibility, limits of quantification (0.03-0.10 µg/L), and enrichment factor (7-14). Matrix-match calibration linearity ranged from 0.03 to 500 µg/L, with determination coefficients (r²) between 0.9884 and 0.9994. Intra-day and inter-day relative standard deviations (RSDs) were 1.2-3.6 % and 7.0-9.3 %, respectively. The composition of the biosorbent and the fabrication reproducibility across different batches were also thoroughly examined. The accuracy was evaluated by measuring extraction recoveries in six environmental water samples, which ranged from 75 to 105 % (RSDs < 9.0 %). Furthermore, the sustainability of the method was evaluated with the Analytical Eco-Scale and Analytical Greenness metrics. To our knowledge, this study represents the first synthesis and combination of [ChCl:[CFA] DES with PES to create a double-layered nanofiber biosorbent, as well as its application for extracting various pesticide groups from water samples.

Facile Synthesis of Aptamer-Functionalized Polydopamine-Coated Magnetic Graphene Oxide Nanocomposites for Highly Efficient Purification of His-Tagged Proteins.

Recombinant proteins hold significant importance in numerous disciplines. As the demand for expressing and purifying these proteins grows, the scientific community is in dire need of a simple yet versatile methodology that can efficiently purify these proteins. Aptamers as synthetic nucleic acid-based ligands with high affinity have shown promise in this regard, as they can capture targets through molecular recognition. In this study, novel aptamer-functionalized polydopamine-coated magnetic graphene oxide nanocomposites were facilely prepared, achieving an impressive average aptamer coverage density (45 nmol/mg). These nanocomposites exhibited a uniform structure and robust magnetic responsiveness. The findings indicated that they possess several advantages, such as rapid adsorption, substantial capacity (171.4 mg/g), and excellent reusability. Notably, due to the inherent properties of nucleic acids, the immobilized aptamer-magnetic beads can be utilized repeatedly with high purification efficiency. Finally, the nanocomposites were further employed to purify His-tagged proteins from actual samples. Remarkably, they were able to selectively and efficiently isolate His-tagged retinoid X receptor alpha protein from complex Escherichia coli lysate. The purified His-tagged retinoid X receptor alpha protein was analyzed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. This confirmed the efficacy of developed nanocomposites, reinforcing their vast potential for purification of His-tagged recombinant proteins.

Visible-light enhanced tetracycline degradation via SnO2/TiO2-Ni@rGO ternary heterostructures.

This study explores the synthesis, characterization, and photocatalytic performance of a SnO2/TiO2-Ni@rGO nanocomposite for tetracycline (TC) degradation under visible light irradiation. The nanocomposite was precisely designed to enhance structural stability, charge transfer efficiency, and catalytic activity. X-ray diffraction (XRD) analysis confirmed the structural integrity of the SnO2/TiO2-Ni@rGO composite, demonstrating excellent reusability and resistance to photo-corrosion after multiple cycles. Photocatalytic experiments revealed that the SnO2/TiO2-Ni@rGO nanocomposite significantly outperformed individual SnO2/TiO2-Ni and rGO catalysts, achieving a remarkable 94.6% degradation of TC within 60 min. The degradation process followed pseudo-first-order kinetics, with a rate constant (k) of 0.046 min-1. The Z-scheme charge transfer mechanism facilitated efficient separation and migration of photogenerated charge carriers, generating reactive oxygen species such as superoxide (•O2 -) and hydroxyl (•OH) radicals crucial for the oxidation of TC. Radical scavenger studies confirmed that superoxide and hydroxyl radicals were the primary active species. The SnO2/TiO2-Ni@rGO composite also exhibited excellent reusability, maintaining high catalytic performance over four consecutive cycles. These findings suggest that the SnO2/TiO2-Ni@rGO nanocomposite is a promising candidate for the efficient and sustainable photocatalytic degradation of persistent organic pollutants like TC, offering significant potential for environmental remediation applications.