Sonochemical synthesis of Fe3O4@NH2-mesoporous silica@Polypyrrole/Pd: A core/double shell nanocomposite for catalytic applications

Advances in silica nanoparticles for agricultural applications and biosynthesis

Nanotechnology has emerged as a revolutionary force in modern agriculture, opening new avenues for crop enhancement and sustainable farming practices. This review systematically evaluates the roles of silica nanoparticles (SiO2 NPs) in agricultural applications, with particular emphasis on their biosynthesis pathways and functional mechanisms. SiO2 NPs have demonstrated considerable potential to enhance crop resilience against both biotic (pathogens, pests) and abiotic (heavy metals, salinity, drought) stresses through phytohormonal regulation, defense gene activation, and metabolic modulation. As nanocarriers, these particles enhance pesticide and fertilizer delivery accuracy, reduce environmental contamination, and promote plant growth. Biosynthesis methods of SiO2 NPs range from conventional physical-chemical techniques to eco-friendly green approaches, including the utilization of biological cells/extracts, natural biomaterials, and peptide templates. Although green synthesis offers sustainability advantages, the agricultural adoption of SiO2 NPs faces critical challenges, such as insufficient understanding of their long-term environmental persistence and ecotoxicological impacts, high production costs related to green synthesis, and incomplete regulatory frameworks. Addressing these challenges is essential to enable their broader use in agriculture.

Deciphering the catalytic activity of nickel anchored on Fe3O4@SiO2@3-CPMS@L as a magnetically recoverable nanocatalyst for the efficacious reduction of 4-nitrophenol, nitrobenzene, and methyl orange

In this paper, a versatile heterogeneous nanocatalyst was fabricated employing a self-assembly technique. To commence, Fe3O4 MNPs were coated with a thin layer of SiO2 using the stobbers method. Subsequently, the surface was further functionalized with 3-CPMS, followed by a reaction with a Schiff base. Finally, nickel NPs were deposited on the surface through in situ deposition, forming the Fe3O4@SiO2@3-CPMS@L-Ni magnetic nanocatalyst. The architecture of this magnetic nanocatalyst was meticulously characterized through an array of sophisticated techniques: XRD, FT-IR, SEM, TEM, BET and VSM. The XRD diffraction pattern confirmed the presence of Fe3O4 MNPs, SiO2, and Ni peaks, providing evidence for successful synthesis. Moreover, the successful functionalization with a Schiff base was demonstrated by the presence of an azomethane peak in the FTIR spectra of the synthesized nanocatalyst. The fabricated nanocatalyst was adeptly utilized for the reduction of 4-NP, NB, and MO demonstrating a remarkably elevated rate of catalytic efficacy. Moreover, this catalyst was effortlessly retrievable through the application of an external magnet, and it maintained its catalytic prowess across at least six consecutive cycles. The utilization of water as an environmentally friendly solvent, coupled with the utilization of abundant and cost-effective nickel catalyst instead of the costly Pd or Pt catalysts, along with the successful recovery and scalability of the catalyst, render this method highly advantageous from both environmental and economic perspectives for the reduction of 4-NP, NB, and MO.

Recent Developments on the Catalytic and Biosensing Applications of Porous Nanomaterials

Nanoscopic materials have demonstrated a versatile role in almost every emerging field of research. Nanomaterials have come to be one of the most important fields of advanced research today due to its controllable particle size in the nanoscale range, capacity to adopt diverse forms and morphologies, high surface area, and involvement of transition and non-transition metals. With the introduction of porosity, nanomaterials have become a more promising candidate than their bulk counterparts in catalysis, biomedicine, drug delivery, and other areas. This review intends to compile a self-contained set of papers related to new synthesis methods and versatile applications of porous nanomaterials that can give a realistic picture of current state-of-the-art research, especially for catalysis and sensor area. Especially, we cover various surface functionalization strategies by improving accessibility and mass transfer limitation of catalytic applications for wide variety of materials, including organic and inorganic materials (metals/metal oxides) with covalent porous organic (COFs) and inorganic (silica/carbon) frameworks, constituting solid backgrounds on porous materials.

An overview and bibliometric analysis on the colorectal cancer therapy by magnetic functionalized nanoparticles for the responsive and targeted drug delivery

With the growing demands for personalized medicine and medical devices, nanomedicine is a modern scientific field, and research continues to apply nanomaterials for therapeutic and damaged tissue diagnosis. In this regard, substantial progress has been made in synthesizing magnetic nanoparticles with desired sizes, chemical composition, morphologies, and surface chemistry. Among these materials, nanomagnetic iron oxides have demonstrated promise as unique drug delivery carriers due to cancer treatment. This carrier could lead to responsive properties to a specific trigger, including heat, pH, alternative magnetic field, or even enzymes, through functionalization and coating of magnetic nanoparticles, along with biocompatibility, good chemical stability, easy functionalization, simple processing, and ability to localize to the tumor site with the assistance of external magnetic field. Current studies have focused on magnetic nanoparticles' utilities in cancer therapy, especially for colorectal cancer. Additionally, a bibliometric investigation was performed on the public trends in the field of the magnetic nanoparticle to drug delivery and anticancer, which represented progressing applications of these carriers in the multidisciplinary zones with a general view on future research and identified potential opportunities and challenges. Furthermore, we outline the current challenges and forthcoming research perspective for high performance and fostering advanced MNPs in colorectal cancer treatment.

Recent advancements and future submissions of silica core-shell nanoparticles

The core-shell silica-based nanoparticles (CSNPs) possess outstanding properties for developing next-generation therapeutics. CSNPs provide greater surface area owing to their mesoporous structure, which offers a high opportunity for surface modification. This review highlights the potential of core-shell silica-based nanoparticle (CSNP) based injectable nanotherapeutics (INT); its role in drug delivery, biomedical imaging, light-triggered phototherapy, Plasmonic enhancers, gene delivery, magnetic hyperthermia, immunotherapy, and potential as next-generation theragnostic. Specifically, the conceptual crosstalk on modern synthetic strategies, biodistribution profiles with a mechanistic view on the therapeutics loading and release modeling are dealt in detail. The manuscript also converses the challenges associated with CSNPs, regulatory hurdles, and their current market position.

The synthesis and characterization of targeted delivery curcumin using chitosan-magnetite-reduced graphene oxide as nano-carrier

To achieve targeted treatment with fewer adverse effects against fatal cancer diseases, the use of nanoparticles as therapeutic agents or drug carriers has been proved to be very extensive and remarkable, today. In this study, chitosan-magnetite-reduced graphene oxide (CS-Fe₃O₄-RGO) nanocomposites (NC) were used for the targeted delivery of curcumin (Cur) as anticancer drugs to suppress MCF-7 breast cancer cells and this was accomplished using a facile water-in-oil (W/O) emulsification procedure. FTIR and XRD were used for characterization. The average size distribution of nanoemulsions and their surface charge (zeta potential) were determined by Dynamic light scattering (DLS) analyzer and zeta potential measurement, respectively. SEM Mapping showed the uniform and flat surface for the NC which was confirmed by the EDX diagram. Measurement of VSM exhibited that the Fe₃O₄-RGOs have superparamagnetic properties. According to the MTT assay, the NC has the highest toxicity at 0.1 against MCF-7 cancer cells. The results of flow cytometry indicated apoptosis in MCF-7 cells. By using the dialysis method, it was determined that curcumin was released faster in an acidic medium. It is expected that the results of this study will be effective in the development of targeted drug delivery as well as the development of CS- Fe₃O₄-RGO-based drug carriers against various cancer cells during future research.

Evaluation of Chitosan Derivatives Modified Mesoporous Silica Nanoparticles as Delivery Carrier

Chitosan is a non-toxic biological material, but chitosan is insoluble in water, which hinders the development and utilization of chitosan. Chitosan derivatives N-2-Hydroxypropyl trimethyl ammonium chloride (N-2-HACC) and carboxymethyl chitosan (CMCS) with good water solubility were synthesized by our laboratory. In this study, we synthesized mesoporous SiO₂ nanoparticles by the emulsion, and then the mesoporous SiO₂ nanoparticles were modified with γ-aminopropyltriethoxysilane to synthesize aminated mesoporous SiO₂ nanoparticles; CMCS and N-2-HACC was used to cross-link the aminated mesoporous SiO₂ nanoparticles to construct SiO₂@CMCS-N-2-HACC nanoparticles. Because the aminated mesoporous SiO₂ nanoparticles with positively charged can react with the mucous membranes, the virus enters the body mainly through mucous membranes, so Newcastle disease virus (NDV) was selected as the model drug to evaluate the performance of the SiO₂@CMCS-N-2-HACC nanoparticles. We prepared the SiO₂@CMCS-N-2-HACC nanoparticles loaded with inactivated NDV (NDV/SiO₂@CMCS-N-2-HACC). The SiO₂@CMCS-N-2-HACC nanoparticles as delivery carrier had high loading capacity, low cytotoxicity, good acid resistance and bile resistance and enteric solubility, and the structure of NDV protein encapsulated in the nano vaccine was not destroyed. In addition, the SiO₂@CMCS-N-2-HACC nanoparticles could sustain slowly released NDV. Therefore, the SiO₂@CMCS-N-2-HACC nanoparticles have the potential to be served as delivery vehicle for vaccine and/or drug.

Sonochemical fabrication of inorganic nanoparticles for applications in catalysis

Catalysis covers almost all the chemical reactions or processes aiming for many applications. Sonochemistry has emerged in designing and developing the synthesis of nano-structured materials, and the latest progress mainly focuses on the synthetic strategies, product properties as well as catalytic applications. This current review simply presents the sonochemical effects under ultrasound irradiation, roughly describes the ultrasound-synthesized inorganic nano-materials, and highlights the sonochemistry applications in the inorganics-based catalysis processes including reduction, oxidation, degradation, polymerization, etc. Or all in all, the review hopes to provide an integrated understanding of sonochemistry, emphasize the great significance of ultrasound-assisted synthesis in structured materials as a unique strategy, and broaden the updated applications of ultrasound irradiation in the catalysis fields.

Folic Acid-Terminated Poly(2-Diethyl Amino Ethyl Methacrylate) Brush-Gated Magnetic Mesoporous Nanoparticles as a Smart Drug Delivery System

Currently, chemotherapy is an important method for the treatment of various cancers. Nevertheless, it has many limitations, such as poor tumour selectivity and multi-drug resistance. It is necessary to improve this treatment method by incorporating a targeted drug delivery system aimed to reduce side effects and drug resistance. The present work aims to develop pH-sensitive nanocarriers containing magnetic mesoporous silica nanoparticles (MMSNs) coated with pH-responsive polymers for tumour-targeted drug delivery via the folate receptor. 2-Diethyl amino ethyl methacrylate (DEAEMA) was successfully grafted on MMSNs via surface initiated ARGET atom transfer radical polymerization (ATRP), with an average particle size of 180 nm. The end groups of poly (2-(diethylamino)ethyl methacrylate) (PDEAEMA) brushes were converted to amines, followed by a covalent bond with folic acid (FA) as a targeting agent. FA conjugated to the nanoparticle surface was confirmed by X-ray photoelectron spectroscopy (XPS). pH-Responsive behavior of PDEAEMA brushes was investigated by Dynamic Light Scattering (DLS). The nanoparticles average diameters ranged from ca. 350 nm in basic media to ca. 650 in acidic solution. Multifunctional pH-sensitive magnetic mesoporous nanoparticles were loaded with an anti-cancer drug (Doxorubicin) to investigate their capacity and long-circulation time. In a cumulative release pattern, doxorubicin (DOX) release from nano-systems was ca. 20% when the particle exposed to acidic media, compared to ca. 5% in basic media. The nano-systems have excellent biocompatibility and are minimally toxic when exposed to MCF-7, and -MCF-7 ADR cells.

Silica Mesoporous Structures: Effective Nanocarriers in Drug Delivery and Nanocatalysts

The application of silica mesoporous structures in drug delivery and the removal of pollutants and organic compounds through catalytic reactions is increasing due to their unique characteristics, including high loading capacities, tunable pores, large surface areas, sustainability, and so on. This review focuses on very well-studied class of different construction mesoporous silica nano(particles), such as MCM-41, SBA-15, and SBA-16. We discuss the essential parameters involved in the synthesis of these materials with providing a diverse set of examples. In addition, the recent advances in silica mesoporous structures for drug delivery and catalytic applications are presented to fill the existing gap in the literature with providing some promising examples on this topic for the scientists in both industry and academia active in the field. Regarding the catalytic applications, mesoporous silica particles have shown some promises to remove the organic pollutants and to synthesize final products with high yields due to the ease with which their surfaces can be modified with various ligands to create appropriate interactions with target molecules. In the drug delivery process, as nanocarriers, they have also shown very good performance thanks to the easy surface functionalization but also adjustability of their porosities to providing in-vivo and in-vitro cargo delivery at the target site with appropriate rate.

Simple Sonochemical Method to Optimize the Heating Efficiency of Magnetic Nanoparticles for Magnetic Fluid Hyperthermia

We developed a fast, single-step sonochemical strategy for the green manufacturing of magnetite (Fe₃O₄) magnetic nanoparticles (MNPs), using iron sulfate (FeSO₄) as the sole source of iron and sodium hydroxide (Na(OH)) as the reducing agent in an aqueous medium. The designed methodology reduces the environmental impact of toxic chemical compounds and minimizes the infrastructure requirements and reaction times down to minutes. The Na(OH) concentration has been varied to optimize the final size and magnetic properties of the MNPs and to minimize the amount of corrosive byproducts of the reaction. The change in the starting FeSO₄ concentration (from 5.4 to 43.1 mM) changed the particle sizes from (20 ± 3) to (58 ± 8) nm. These magnetite MNPs are promising for biomedical applications due to their negative surface charge, good heating properties (≈324 ± 2 W/g), and low cytotoxic effects. These results indicate the potential of this controlled, easy, and rapid ultrasonic irradiation method to prepare nanomaterials with enhanced properties and good potential for use as magnetic hyperthermia agents.

Colorimetric detection of insulin in human serum using GO/AuNPs/TX-100 nanocomposite

In this study, graphene oxide/gold nanoparticles/Triton X-100 nanocomposites (GO/AuNPs/TX-100) were synthesized using the sonochemical method and their ability in ultrasound-assisted colorimetric detection of insulin was investigated. The synthesized GO/AuNPs/TX-100 nanocomposites were characterized by UV-visible absorption spectroscopy and TEM analysis. The interaction between the nanocomposites and insulin was observed by both naked eye and optical absorption spectroscopy. The GO/AuNPs/TX-100 nanocomposites displayed apparent color changes (red to blue) and absorption spectra changes (decreasing of the band around 528 nm and appearance of a new red-shifted band at 640 nm) in presence of insulin. The interaction mechanism of the nanocomposites and insulin was discussed. It is based on the special structure of insulin, that insulin can be easily self-assemble into the GO/AuNP/TX-100 nanocomposites and can also play the role of a bridge between two different GO/AuNPs/TX-100 nanocomposites by peptide chains. The effective parameters for insulin detection were optimized. The colorimetric method was used for quantification of insulin in the range of 2-300 ng mL^-1 with a detection limit of 0.1 ng mL^-1. Moreover, the relative standard deviation of the method was 3.1 and 2.7% (n = 10) at concentrations of 50 and 200 ng mL^-1, respectively on the same day and 4.8% at a concentration (200.0 ng mL^-1) on five consecutive days. The present method was utilized for insulin assay in human blood serums with satisfactory results.

Functionalized mesoporous SBA-15 silica: recent trends and catalytic applications

The development of advanced materials for heterogeneous catalytic applications requires fine control over the synthesis and structural parameters of the active site. Mesoporous silica materials have attracted increasing attention to be considered as an important class of nanostructured support materials in heterogeneous catalysis. Their large surface area, well-defined porous architecture and ability to incorporate metal atoms within the mesopores lead them to be a promising support material for designing a variety of different catalysts. In particular, SBA-15 mesoporous silica has its broad applicability in catalysis because of its comparatively thicker walls leading to higher thermal and mechanical stability. In this review article, various strategies to functionalize SBA-15 mesoporous silica have been reviewed with a view to evaluating its efficacy in different catalytic transformation reactions. Special attention has been given to the molecular engineering of the silica surface, within the framework and within the hexagonal mesoporous channels for anchoring metal oxides, single-site species and metal nanoparticles (NPs) serving as catalytically active sites.

Functional group-rich hyperbranched magnetic material for simultaneous efficient removal of heavy metal ions from aqueous solution

In order to achieve the purpose of simultaneous removal of coexisting heavy metal ions, in this work, functionalized magnetic mesoprous nanomaterials (Fe₃O₄-HBPA-ASA) with high density and multiple adsorption sites were designed and prepared. The obtained Fe₃O₄-HBPA-ASA was characterized by SEM, FTIR, VSM, TGA and zeta potential. Cu(II), Pb(II) and Cd(II) were chosen as the model heavy metal ions, the adsorption experiments showed that Fe₃O₄-HBPA-ASA showed hightheoretical adsorption capacitiesin individual system, and the maximum adsorption capacity was 136.66 mg/g, 88.36 mg/g and 165.46 mg/g, respectively. In the binary and ternary systems, the competitive adsorption leads to a decrease in the adsorption capacity of Cu(II), Pb(II) and Cd(II). However, in the ternary system with a concentration lower than 15 mg/L, the simultaneous removal rate was still higher than 90%. The adsorption isotherms and kineticswere well fitted by Langmuir and pseudo-second-order models, respectively. The XPS and density functional theory (DFT) analysis have confirmed that the adsorption of metal ions was related to various types of functional groups on the surface of Fe₃O₄-HBPA-ASA, while the adsorption mechanisms of Cu(II), Cd(II) and Pb(II) were different.

Synergistic catalytic effect between ultrasound waves and pyrimidine-2,4-diamine-functionalized magnetic nanoparticles: Applied for synthesis of 1,4-dihydropyridine pharmaceutical derivatives

A convenient strategy for synthesis of the various derivatives of 1,4-dihydropyridine (1,4-DHP), as one of the most important pharmaceutical compounds, is presented in this study. For this purpose, firstly, magnetic iron oxide nanoparticles (Fe₃O₄ NPs) were fabricated and suitably coated by silica network (SiO₂) and trimethoxy vinylsilane (TMVS). Then, their surfaces were well functionalized with pyrimidine-2,4-diamine (PDA) as the main active sites for catalyzing the synthesis reactions. In this regard, the performance of three different methods including reflux, microwave (MW) and ultrasound wave (USW) irradiations have been comparatively monitored via studying various analyses on the fabricated nanocatalyst (Fe₃O₄/SiO₂-PDA). Concisely, high efficiency of the USW irradiation (in an ultrasound cleaning bath with a frequency of 50 kHz and power of 250 W/L) has been well proven through the investigation of the main factors such as excellent surface-functionalization, core/shell structure conservation, particle uniformity, close size distribution of the particles, and great inhibition of the particle aggregation. Then, the effectiveness of the USW irradiation as a promising co-catalyst agent has been clearly demonstrated in the 1,4-DHP synthesis reactions. It has been concluded that the USW could provide more appropriate conditions for activation of the catalytic sites of Fe₃O₄/SiO₂-PDA NPs. However, high reaction yields (89%) have been obtained in the short reaction times (10 min) due to the substantial synergistic effect between the presented nanocatalyst and USW.

Rational design of a polypyrrole-based competent bifunctional magnetic nanocatalyst

The combination of conducting polymers with semiconductors for the fabrication of organic/inorganic hybrid nanocatalysts is one of the most promising research areas for many applications. In this work, the synthesized nanocomposite combines several advantages such as the photoresponse shift from the UV region toward visible light by narrowing the band gap of the semiconductor, magnetic separation ability and dual applications including the catalytic reduction of p-nitrophenol (PNP) and the photocatalytic degradation of methylene blue (MB) dye. In addition to the core magnetite nanoparticles (NPs), the synthesized nanocomposite contains polypyrrole (PPY) and TiO₂ shells that are decorated with silver metal NPs to prevent electron–hole recombination and to enhance the catalytic performance. Indeed, the catalytic PNP reduction experiments reveal that the synthesized nanocomposite exhibits significantly high catalytic activity with a rate constant of 0.1169 min⁻¹. Moreover, the photocatalytic experiments show that the synthesized nanophotocatalyst has a boosting effect toward MB dye degradation under normal daytime visible light irradiation with a rate constant of 6.38 × 10⁻² min⁻¹. The synergetic effect between silver NPs, PPY and TiO₂ is thought to play a fundamental role in enhancing the photocatalytic activity.

An efficient method to synthesize a magnetic nanocomposite with dual catalytic activities with a synergetic effect between Ag nanoparticles, polypyrrole and TiO₂ is described.

Ultrasonic polymerization of CuO@PNIPAM and its temperature tuning glucose sensing behavior

The extraordinary high pressure and temperature produced during cavitation is crucial for ultrasonic sonochemistry. However, the cavitation effect is usually confined to a small zone nearby the ultrasonic horn, outside of which ultrasound produces much less effects on chemical reaction. In present work, in order to expand the range of effective zone and intensify the cavitation effect, N₂ aeration was introduced to an ultrasonic polymerization process of CuO@PNIPAM in aqueous solution. By increasing the number of bubble nucleus gathered on the CuO surface and lowering the surface tension of the aqueous solution, the cavitation effect is intensified on the CuO surface within the whole reaction vessel, which benefits the covalently bonding between PNIPAM and CuO to a large degree and results in the formation of CuO@PNIPAM hybrid composite with excellent interfacial bonding. It is promising that the hybrid composite can be applied as temperature responsive glucose sensing platform with ON and OFF states due to the wettability change of PNIPAM versus temperature.

Mesoporous Silica Nanoparticles: A Comprehensive Review on Synthesis and Recent Advances

Recent advancements in drug delivery technologies utilizing a variety of carriers have resulted in a path-breaking revolution in the approach towards diagnosis and therapy alike in the current times. Need for materials with high thermal, chemical and mechanical properties have led to the development of mesoporous silica nanoparticles (MSNs). These ordered porous materials have garnered immense attention as drug carriers owing to their distinctive features over the others. They can be synthesized using a relatively simple process, thus making it cost effective. Moreover, by controlling the parameters during the synthesis; the morphology, pore size and volume and particle size can be transformed accordingly. Over the last few years, a rapid increase in research on MSNs as drug carriers for the treatment of various diseases has been observed indicating its potential benefits in drug delivery. Their widespread application for the loading of small molecules as well as macromolecules such as proteins, siRNA and so forth, has made it a versatile carrier. In the recent times, researchers have sorted to several modifications in the framework of MSNs to explore its potential in drug resistant chemotherapy, antimicrobial therapy. In this review, we have discussed the synthesis of these multitalented nanoparticles and the factors influencing the size and morphology of this wonder carrier. The second part of this review emphasizes on the applications and the advances made in the MSNs to broaden the spectrum of its use especially in the field of biomedicine. We have also touched upon the lacunae in the thorough understanding of its interaction with a biological system which poses a major hurdle in the passage of this carrier to the clinical level. In the final part of this review, we have discussed some of the major patents filed in the field of MSNs for therapeutic purpose.

Seedless synthesis and efficient recyclable catalytic activity of Ag@Fe nanocomposites towards methyl orange

This work demonstrates a competitive reduction method of synthesis of nanomaterials. In this method along cetyltrimethylammonium bromide (CTAB), the reduction of Ag+ and Fe3+ ions is achieved by ascorbic acid-to-bimetallic Ag@Fe yellow-colored nanomaterials. The shape of UV–visible spectra and wavelengths absorbed of Ag@Fe can be tuned from ca. 290–600 nm by controlling [CTAB] and [Ag+]. The apparent first-order rate constants were calculated within the approximation of 6.1 × 10−3 s−1. The as-prepared Ag@Fe NPs have been found to be very important catalyst in terms of depredate methyl orange in vicinity of sodium borohydride (NaBH4), which exhibits excellent efficiency and re-usability in the prototypical reaction. The cmc of cationic surfactant CTAB has been determined by conductivity method under different experimental conditions. In the presence of CTAB, Ag+ and Fe3+ ions reduce to Ag@Fe core/shell nanoparticles, comprehend a change in wavelength and intensity of SRP band. The apparent first-order rate constant, activation energy, and turnover frequency for the methyl orange reduction catalyzed by Ag@Fe NPs were found to be 1.6 × 10−3 s−1, 58.2 kJ mol−1, and 1.1 × 10−3 s−1, respectively.