The ZnFe2O4@mZnO–N/RGO nano-composite as a carrier and an intelligent releaser drug with dual pH- and ultrasound-triggered control

Supported of gold nanoparticles on carboxymethyl lignin modified magnetic nanoparticles as an efficient catalyst for reduction of nitroarenes and treatment of human melanoma

This article represents the synthesis and characterizations of Au NPs immobilized and carboxymethyl lignin (CML) modified Fe3O4 nanoparticles (Fe3O4@CML/Au NPs) following a bio-inspired protocol without the participation of any toxic and harmful reductant or stabilizers. Following various physicochemical methodologies, such as FT-IR, FE-SEM, TEM, EDX, XRD, VSM, and ICP-OES, the textural characteristics and different structural aspects were evaluated. The Fe3O4@CML/Au NPs nanocomposite was subsequently explored towards the catalytic reduction of diverse aromatic nitro functions using green conditions. An excellent yield were achieved within very short reaction time. Nine recycling runs of the nanocatalyst were completed without a discernible loss of catalytic activity, thanks to its easy magnetic recovery. The DPPH assay was carried out to examine the antioxidant effectiveness. The Fe3O4@CML/Au NPs nanocomposite inhibited half of the DPPH in a 250 μg/mL solution. To measure the anti-human melanoma efficacy of Fe3O4@CML/Au NPs nanocomposite, MTT assay was applied on HT144, MUM2C, IPC-298 and SKMEL24 cell lines. Fe3O4@CML/Au NPs nanocomposite had high anti-human melanoma efficacy on above tumor cells. The best finding of anti-human melanoma properties of Fe3O4@CML/Au NPs nanocomposite was seen in the case of the SKMEL24 cell line. The IC50 of Fe3O4@CML/Au NPs nanocomposite was 137, 145, 185, and 125 μg/mL against HT144, MUM2C, IPC-298 and SKMEL24 cells, respectively. This research exhibited remarkable anti-human melanoma and antioxidant efficacies of Fe3O4@CML/Au NPs nanocomposite in the in vitro condition.

Metal nanoparticles as a potential technique for the diagnosis and treatment of gastrointestinal cancer: a comprehensive review

Gastrointestinal (GI) cancer is a major health problem worldwide, and current diagnostic and therapeutic approaches are often inadequate. Various metallic nanoparticles (MNPs) have been widely studied for several biomedical applications, including cancer. They may potentially overcome the challenges associated with conventional chemotherapy and significantly impact the overall survival of GI cancer patients. Functionalized MNPs with targeted ligands provide more efficient localization of tumor energy deposition, better solubility and stability, and specific targeting properties. In addition to enhanced therapeutic efficacy, MNPs are also a diagnostic tool for molecular imaging of malignant lesions, enabling non-invasive imaging or detection of tumor-specific or tumor-associated antigens. MNP-based therapeutic systems enable simultaneous stability and solubility of encapsulated drugs and regulate the delivery of therapeutic agents directly to tumor cells, which improves therapeutic efficacy and minimizes drug toxicity and leakage into normal cells. However, metal nanoparticles have been shown to have a cytotoxic effect on cells in vitro. This can be a concern when using metal nanoparticles for cancer treatment, as they may also kill healthy cells in addition to cancer cells. In this review, we provide an overview of the current state of the field, including preparation methods of MNPs, clinical applications, and advances in their use in targeted GI cancer therapy, as well as the advantages and limitations of using metal nanoparticles for the diagnosis and treatment of gastrointestinal cancer such as potential toxicity. We also discuss potential future directions and areas for further research, including the development of novel MNP-based approaches and the optimization of existing approaches.

Green synthesised zinc oxide nanoparticles reveal potent in vivo and in vitro antibacterial efficacy against Proteus mirabilis isolates

Currently, the spread of antimicrobial resistance dissemination is expanding at an accelerated rate. Therefore, numerous researchers haveinvestigatedalternative treatments in an effort to combat this significant issue. This study evaluated the antibacterial properties of zinc-oxide nanoparticles (ZnO NPs) synthesised by Cycas circinalis against Proteus mirabilis clinical isolates. HPLC was utilised for the identification and quantification of C. circinalis metabolites. The green synthesis of ZnO NPs has been confirmed using UV-VIS spectrophotometry. The Fourier transform infrared spectrum of metal oxide bonds has been compared to the free C. circinalis extract spectrum. The crystalline structure and elemental composition were investigated using X-ray diffraction and Energy-dispersive X-ray techniques. The morphology of nanoparticles was assessed by scanning and transmission electron microscopies, which revealed an average particle size of 26.83±5.87 nm with spherical outlines. The dynamic light scattering technique confirms the optimum stability of ZnO NPs with a zeta potential value equal to 26.4±0.49 mV. Using agar well diffusion and broth microdilution methods, we elucidated the antibacterial activity of ZnO NPs in vitro. MIC values for ZnO NPs ranged from 32 to 128 µg/mL. In 50% of the tested isolates, the membrane integrity was compromised by ZnO nanoparticles. In addition, we assessed the in vivo antibacterial capacity of ZnO NPs by a systemic infection induction using P. mirabilis bacteria in mice. The bacterial count in the kidney tissues was determined, and a significant decrease in CFU/g tissues was observed. The survival rate was evaluated, and the ZnO NPs treated group had higher survival rates. The histopathological studies demonstrated that kidney tissues treated with ZnO NPs had normal structures and architecture. Moreover, the immunohistochemical examinations and ELISA revealed that ZnO NPs substantially decreased the proinflammatory mediators NF-kβ, COX-2, TNF-α, IL-6, and IL-1β in kidney tissues. In conclusion, the results of this study suggest that ZnO NPs are effective against bacterial infections caused by P. mirabilis.

Metal Oxide Nanoparticles: Review of Synthesis, Characterization and Biological Effects

In the last few years, the progress made in the field of nanotechnology has allowed researchers to develop and synthesize nanosized materials with unique physicochemical characteristics, suitable for various biomedical applications. Amongst these nanomaterials, metal oxide nanoparticles (MONPs) have gained increasing interest due to their excellent properties, which to a great extent differ from their bulk counterpart. However, despite such positive advantages, a substantial body of literature reports on their cytotoxic effects, which are directly correlated to the nanoparticles' physicochemical properties, therefore, better control over the synthetic parameters will not only lead to favorable surface characteristics but may also increase biocompatibility and consequently lower cytotoxicity. Taking into consideration the enormous biomedical potential of MONPs, the present review will discuss the most recent developments in this field referring mainly to synthesis methods, physical and chemical characterization and biological effects, including the pro-regenerative and antitumor potentials as well as antibacterial activity. Moreover, the last section of the review will tackle the pressing issue of the toxic effects of MONPs on various tissues/organs and cell lines.

Nano-architectural design of TiO2 for high performance photocatalytic degradation of organic pollutant: A review

In the past several decades, significant efforts have been paid toward photocatalytic degradation of organic pollutants in environmental research. During the past years, titanium dioxide nano-architectures (TiO₂ NAs) have been widely used in water purification applications with photocatalytic degradation processes under Uv/Vis light illumination. Photocatalysis process with nano-architectural design of TiO₂ is viewed as an efficient procedure for directly channeling solar energy into water treatment reactions. The considerable band-gap values and the subsequent short life time of photo-generated charge carriers are showed among the limitations of this approach. One of these effective efforts is the using of oxidation processes with advance semiconductor photocatalyst NAs for degradation the organic pollutants under UV/Vis irradiation. Among them, nano-architectural design of TiO₂ photocatalyst (such as Janus, yolk-shell (Y@S), hollow microspheres (HMSs) and nano-belt) is an effective way to improve oxidation processes for increasing photocatalytic activity in water treatment applications. In the light of the above issues, this study tends to provide a critical overview of the used strategies for preparing TiO₂ photocatalysts with desirable physicochemical properties like enhanced absorption of light, low density, high surface area, photo-stability, and charge-carrier behavior. Among the various nanoarchitectural design of TiO₂, the Y@S and HMSs have created a great appeal given their considerable large surface area, low density, homogeneous catalytic environment, favorable light harvesting properties, and enhanced molecular diffusion kinetics of the particles. In this review was summarized the developments that have been made for nano-architectural design of TiO2 photocatalyst. Additional focus is placed on the realization of interfacial charge and the possibility of achieving charge carriers separation for these NAs as electron migration is the extremely important factor for increasing the photocatalytic activity.

Utility of Biogenic Iron and Its Bimetallic Nanocomposites for Biomedical Applications: A Review

Nanotechnology mainly deals with the production and application of compounds with dimensions in nanoscale. Given their dimensions, these materials have considerable surface/volume ratios, and hence, specific characteristics. Nowadays, environmentally friendly procedures are being proposed for fabrication of Fe nanoparticles because a large amount of poisonous chemicals and unfavorable conditions are needed to prepare them. This work includes an inclusive overview on the economical and green procedures for the preparation of such nanoparticles (flower, fruits, tea, carbohydrates, and leaves). Pure and bimetallic iron nanoparticles, for instance, offer a high bandwidth and excitation binding energy and are applicable in different areas ranging from antibacterial, anticancer, and bioimaging agents to drug delivery systems. Preparation of nano-sized particles, such as those of Fe, requires the application of high quantities of toxic materials and harsh conditions, and naturally, there is a tendency to develop more facile and even green pathways (Sultana, Journal of Materials Science & Technology, 2013, 29, 795–800; Bushra et al., Journal of hazardous materials, 2014, 264, 481–489; Khan et al., Ind. Eng. Chem. Res., 2015, 54, 76–82). This article tends to provide an overview on the reports describing green and biological methods for the synthesis of Fe nanoparticles. The present review mainly highlights selenium nanoparticles in the biomedical domain. Specifically, this review will present detailed information on drug delivery, bioimaging, antibacterial, and anticancer activity. It will also focus on procedures for their green synthesis methods and properties that make them potential candidates for various biomedical applications. Finally, we provide a detailed future outlook.

Supermagnetic Mn-substituted ZnFe2O4 with AB-site hybridization for the ultra-effective catalytic degradation of azoxystrobin

Magnetic Zn0.25Mn0.75Fe2O4 was applied to the degradation of azoxystrobin in a Fenton-like system, and the performance was enhanced via crystal structure control.

Stimulus-responsive nanomaterials under physical regulation for biomedical applications

Cancer is a growing threat to human beings. Traditional treatments for malignant tumors usually involve invasive means to healthy human tissues, such as surgical treatment and chemotherapy. In recent years the use of specific stimulus-responsive materials in combination with some non-contact, non-invasive stimuli can lead to better efficacy and has become an important area of research. It promises to develop personalized treatment systems for four types of physical stimuli: light, ultrasound, magnetic field, and temperature. Nanomaterials that are responsive to these stimuli can be used to enhance drug delivery, cancer treatment, and tissue engineering. This paper reviews the principles of the stimuli mentioned above, their effects on materials, and how they work with nanomaterials. For this aim, we focus on specific applications in controlled drug release, cancer therapy, tissue engineering, and virus detection, with particular reference to recent photothermal, photodynamic, sonodynamic, magnetothermal, radiation, and other types of therapies. It is instructive for the future development of stimulus-responsive nanomaterials for these aspects.

Fabrication of an SPME fiber based on ZnO@GA nanorods coated onto fused silica as a highly efficient absorbent for the analysis of cancer VOCs in water and urine

Analysis of volatile organic compounds (VOCs) secreted in urine, blood, breath, etc. is a new method for monitoring the metabolism and biochemistry of the human body. However, due to the complexity of samples, a pre-concentration step is necessary before the final analysis with gas chromatography-mass spectroscopy (GC-MS). Therefore, miniaturized extraction methods such as solid-phase microextraction (SPME) can be a promising and simple pre-concentration technique. Different strategies have been adopted for the fabrication or modification of SPME fibers. This study presents the preparation and characterization of glass optical fibers coated with ZnO nanorods functionalized with gallic acid (ZnO@GA nanorod) as SPME adsorbent in GC-MS. ZnO@GA nanorods were synthesized separately and then coated onto the fibers. The coated fibers were characterized by using field emission scanning electron microscopy coupled with energy dispersive analysis of X-rays (FESEM/EDAX) and Fourier transform infrared spectroscopy (FTIR) techniques. Possessing a high surface to volume ratio of ZnO nanorods and functional groups of GA, the ZnO@GA nanorod-based SPME fibers exhibited good extraction performance for VOCs comparing with the commercial polydimethylsiloxane (PDMS) coated fibers. Under optimal conditions (NaCl concentration, 30% w/v; extraction time of 25 min; pH, 5-7 and stirring rate of 400 rpm) ZnO@GA nanorods coated fibers achieved low detection limits (0.32-4.8 μg/L), low quantification limits (1.8-16.3 μg/L) and good linearity (5-1000 μg/L) for selected VOCs. The repeatability (n = 3) for a single fiber was within the range of 4.1-7.9% (intra-day) and 5.7-9.6% (inter-day) while the reproducibility (n = 3) of fiber-to-fiber were in the range of 4.7% and 9.9%. This method was successfully used for the determination of six VOCs in water and urine with satisfactory recoveries of 90-112%. ZnO@GA nanorod coated fibers, despite possessing a much thinner coating compared to the commercial fibers, revealed a better overall extraction efficiency towards VOCs. These results indicated that the ZnO@GA provided a promising alternative in sample pretreatment and analysis in GC-MS.

Adsorption of Cationic Dyes on a Magnetic 3D Spongin Scaffold with Nano-Sized Fe3O4 Cores

The renewable, proteinaceous, marine biopolymer spongin is yet the focus of modern research. The preparation of a magnetic three-dimensional (3D) spongin scaffold with nano-sized Fe3O4 cores is reported here for the first time. The formation of this magnetic spongin-Fe3O4 composite was characterized by X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential thermal analysis (DTA) (TGA-DTA), vibrating sample magnetometer (VSM), Fourier-transform infrared spectroscopy (FTIR), and zeta potential analyses. Field emission scanning electron microscopy (FE-SEM) confirmed the formation of well-dispersed spherical nanoparticles tightly bound to the spongin scaffold. The magnetic spongin-Fe3O4 composite showed significant removal efficiency for two cationic dyes (i.e., crystal violet (CV) and methylene blue (MB)). Adsorption experiments revealed that the prepared material is a fast, high-capacity (77 mg/g), yet selective adsorbent for MB. This behavior was attributed to the creation of strong electrostatic interactions between the spongin-Fe3O4 and MB or CV, which was reflected by adsorption mechanism evaluations. The adsorption of MB and CV was found to be a function of pH, with maximum removal performance being observed over a wide pH range (pH = 5.5-11). In this work, we combined Fe3O4 nanoparticles and spongin scaffold properties into one unique composite, named magnetic spongin scaffold, in our attempt to create a sustainable absorbent for organic wastewater treatment. The appropriative mechanism of adsorption of the cationic dyes on a magnetic 3D spongin scaffold is proposed. Removal of organic dyes and other contaminants is essential to ensure healthy water and prevent various diseases. On the other hand, in many cases, dyes are used as models to demonstrate the adsorption properties of nanostructures. Due to the good absorption properties of magnetic spongin, it can be proposed as a green and uncomplicated adsorbent for the removal of different organic contaminants and, furthermore, as a carrier in drug delivery applications.