Facile synthesis of Cu NPs@Fe3O4-lignosulfonate: Study of catalytic and antibacterial/antioxidant activities.

Environmental pollution is one of the important concerns for human health. There are different types of pollutants and techniques to eliminate them from the environment. We hereby report an efficient method for the remediation of environmental contaminants through the catalytic reduction of the selected pollutants. A green method has been developed for the immobilization of copper nanoparticles on magnetic lignosulfonate (Cu NPs@Fe3O4-LS) using the aqueous extract of Filago arvensis L. as a non-toxic reducing and stabilizing agent. The characterization of the prepared Cu NPs@Fe3O4-LS was achieved by vibrating sample magnetometer (VSM), Fourier-transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), high resolution TEM (HRTEM), X-ray diffraction (XRD), scanning TEM (STEM), thermogravimetry-differential thermal analysis (TG/DTA), fast Fourier transform (FFT), energy-dispersive X-ray spectroscopy (EDS), and X-ray photoelectron (XPS) analyses. The synthesized Cu NPs@Fe3O4-LS was applied as a magnetic and green catalyst in the reduction of congo red (CR), 4-nitrophenol (4-NP), and methylene blue (MB). The progress of the reduction reactions was monitored by UV-Vis spectroscopy. Finally, the biological properties of Cu NPs@Fe3O4-LS were investigated. The prepared catalyst demonstrated excellent catalytic efficiency in the reduction of CR, 4-NP, and MB in the presence of sodium borohydride (NaBH4) as the reducing agent. The appropriate magnetism of Cu NPs@Fe3O4-LS made its recovery very simple. The advantages of this process include a simple reaction set-up, high and catalytic antibacterial/antioxidant activities, short reaction time, environmentally friendliness, high stability, and easy separation of the catalyst. In addition, the prepared Cu NPs@Fe3O4-LS could be reused for four cycles with no significant decline in performance.

A screen printed electrode modified with Fe3O4@polypyrrole-Pt core-shell nanoparticles for electrochemical detection of 6-mercaptopurine and 6-thioguanine.

In this paper, Fe3O4@ppy-Pt core-shell nanoparticles (NPs) could be produced and utilized for the development of a novel electrochemical sensor to detect 6-mercaptopurine (6-MP). 6-MP determination was examined by cyclic voltammetry (CV), chronoamperometry (CHA), linear sweep voltammetry (LSV), and differential pulse voltammetry (DPV) at Fe3O4@ppy-Pt core-shell NPs modified screen printed electrode (Fe3O4@ppy-Pt/SPE) in phosphate buffered solution (PBS). The outcomes obtained from DPV demonstrated that the Fe3O4@ppy-Pt/SPE proved a linear concentration range among 0.04 and 330.0 µM having a detection limit of 10.0 nM for 6-MP. Also, modified electrode was satisfactorily utilized to detect 6-MP in the presence of 6-thioguanine (6-TG). This sensor showed two separate oxidative peaks at 530 mV for 6-MP and at 730 mV for 6-TG with a peak potential separation of 200 mV which was large enough for simultaneous detection of the two anticancer drugs. In addition, the proposed sensor presented long-term stability, good repeatability, and excellent reproducibility. Finally, the modified electrode demonstrated satisfactory outcomes while used in real samples, proposing the appropriate potential of Fe3O4@ppy-Pt/SPE in the case of clinical diagnosis, biological samples and pharmaceutical compounds analysis.

Natural Polymers Decorated MOF-MXene Nanocarriers for Co-delivery of Doxorubicin/pCRISPR.

A one-pot and facile method with assistance of high gravity was applied for the synthesis of inorganic two-dimensional MOF-5 embedded MXene nanostructures. The innovative inorganic MXene/MOF-5 nanostructure was applied in co-delivery of drug and gene, and to increase its bioavailability and interaction with the pCRISPR, the nanomaterial was coated with alginate and chitosan. The polymer-coated nanosystems were fully characterized, and the sustained DOX delivery and comprehensive cytotoxicity studies were conducted on the HEK-293, PC12, HepG2, and HeLa cell lines, demonstrating acceptable and excellent cell viability at both very low (0.1 µg.mL-1) and high (10 µg·mL-1) concentrations. The chitosan-coated nanocarriers showed superior relative cell viability compared to others, more than 60% on average of relative cell viability in all of the cell lines. Then, alginate-coated nanocarriers ranked at second place on the higher relative cell viability, more than 50% on average for all of the cell lines. Also, MTT results showed a complete dose-dependence, and by increasing the time of treatment from 24 to 72 h, the relative cell viability decreased by a meaningful slope; however, this decrease was optimized by coating the nanocarrier with chitosan and alginate. The nanosystems were also tagged with pCRISPR to analyze the potential application in the co-delivery of drug/gene. CLSM images of the HEK-293 and HeLa cell lines unveiled successful delivery of pCRISPR into the cells, and the enhanced green fluorescent protein (EGFP) reached up to ca. 26% for the HeLa cell line. Also, a considerable drug payload of 35.7% was achieved, which would be because of the interactions between the nanocarrier and the doxorubicin. In this unprecedented report pertaining to the synthesis of MXene assisted by a MOF and high-gravity technique, the methodology and the optimized ensuing MXene/MOF-5 nanosystems can be further developed for the co-delivery of drug/gene in animal models.

Polymer-Coated NH2-UiO-66 for the Codelivery of DOX/pCRISPR.

Herein, the NH2-UiO-66 metal organic framework (MOF) has been green synthesized with the assistance of high gravity to provide a suitable and safe platform for drug loading. The NH2-UiO-66 MOF was characterized using a field-emission scanning electron microscope, transmission electron microscope (TEM), X-ray diffraction, and zeta potential analysis. Doxorubicin was then encapsulated physically on the porosity of the green MOF. Two different stimulus polymers, p(HEMA) and p(NIPAM), were used as the coating agents of the MOFs. Doxorubicin was loaded onto the polymer-coated MOFs as well, and a drug payload of more than 51% was obtained, which is a record by itself. In the next step, pCRISPR was successfully tagged on the surface of the modified MOFs, and the performance of the final nanosystems were evaluated by the GFP expression. In addition, successful loadings and internalizations of doxorubicin were investigated via confocal laser scanning microscopy. Cellular images from the HeLa cell line for the UiO-66@DOX@pCRISPR and GMA-UiO-66@DOX@pCRISPR do not show any promising and successful gene transfections, with a maximum EGFP of 1.6%; however, the results for the p(HEMA)-GMA-UiO-66@DOX@pCRISPR show up to 4.3% transfection efficiency. Also, the results for the p(NIPAM)-GMA-UiO-66@DOX@pCRISPR showed up to 6.4% transfection efficiency, which is the first and superior report of a MOF-based nanocarrier for the delivery of pCRISPR. Furthermore, the MTT assay does not shown any critical cytotoxicity, which is a promising result for further biomedical applications. At the end of the study, the morphologies of all of the nanomaterials were screened after drug and gene delivery procedures and showed partial degradation of the nanomaterial. However, the cubic structure of the MOFs has been shown in TEM, and this is further proof of the stability of these green MOFs for biomedical applications.

Facile synthesis of graphitic carbon nitride/chitosan/Au nanocomposite: A catalyst for electrochemical hydrogen evolution.

This paper reports a novel nanocomposite catalyst comprised of graphitic carbon nitride (g-C3N4), chitosan and gold (Au) nanoparticles, which has been prepared through a facile, clean and low cost method. Graphitic carbon nitride has been fabricated by pyrolysis of urea. Laser ablation in liquid (LAL) was employed in the green synthesis of Au NPs. The g-C3N4/chitosan/Au nanocomposite (denoted as CN/CS/Au) were characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), energy dispersive X-ray spectrometry (EDS), scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET) analyses. Chitosan biopolymer and a small amount of Au NPs were added to g-C3N4 to modify and improve the catalytic activity of g-C3N4. The activity of the hydrogen evolution reaction (HER) has been investigated using CN/CS/Au nanocomposite coated on a stainless steel mesh by electrochemical method. The amounts of hydrogen stored were calculated from cyclic voltammetry (CV) results. The results confirmed that chitosan and Au NPs were effective on the HER behavior of g-C3N4 and the nanocomposite had a good HER activity and stability.

Wrap-bake-peel process for nanostructural transformation from beta-FeOOH nanorods to biocompatible iron oxide nanocapsules.

The thermal treatment of nanostructured materials to improve their properties generally results in undesirable aggregation and sintering. Here, we report on a novel wrap-bake-peel process, which involves silica coating, heat treatment and finally the removal of the silica layer, to transform the phases and structures of nanostructured materials while preserving their nanostructural characteristics. We demonstrate, as a proof-of-concept, the fabrication of water-dispersible and biocompatible hollow iron oxide nanocapsules by applying this wrap-bake-peel process to spindle-shaped akagenite (beta-FeOOH) nanoparticles. Depending on the heat treatment conditions, hollow nanocapsules of either haematite or magnetite were produced. The synthesized water-dispersible magnetite nanocapsules were successfully used not only as a drug-delivery vehicle, but also as a T2 magnetic resonance imaging contrast agent. The current process is generally applicable, and was used to transform heterostructured FePt nanoparticles to high-temperature face-centred-tetragonal-phase FePt alloy nanocrystals.

Nanomaterials for bone tissue regeneration: updates and future perspectives.

Joint replacement and bone reconstructive surgeries are on the rise globally. Current strategies for implants and bone regeneration are associated with poor integration and healing resulting in repeated surgeries. A multidisciplinary approach involving basic biological sciences, tissue engineering, regenerative medicine and clinical research is required to overcome this problem. Considering the nanostructured nature of bone, expertise and resources available through recent advancements in nanobiotechnology enable researchers to design and fabricate devices and drug delivery systems at the nanoscale to be more compatible with the bone tissue environment. The focus of this review is to present the recent progress made in the rationale and design of nanomaterials for tissue engineering and drug delivery relevant to bone regeneration.