Effective gene delivery using size dependant nano core-shell in human cervical cancer cell lines by magnetofection

Biocompatible magnetic nanoparticles are effective for gene delivery in vitro and in vivo transfection. These mediators are mainly used to deliver drugs and genes. It can also be used as probes to diagnose and treat various diseases. Magnetic nanoparticles, primarily iron oxide nanoparticles, are used in various biological applications. However, preparing stable and small-size biocompatible core-shell is crucial in site direct gene delivery. In the present study, superparamagnetic iron oxide nanoparticles were synthesized using the chemical co-precipitation method and were functionalized with starch to attain stable particles. These SPIONs were coated with polyethylenimine to give a net positive charge. The fluorescent plasmid DNA bound to the SPIONs were used as a core shell for gene delivery into the HeLa cells via magnetofection. UV-Visible Spectrophotometry analysis showed a peak at 200 nm, which confirms the presence of FeO nanoparticles. The Scanning Electron Microscopy images revealed the formation of spherical-shaped nanoparticles with an average size of 10 nm. X-ray Diffraction also confirmed FeO as a significant constituent element. Vibrating Sample Magnetometry ensures that the nanoparticles are superparamagnetic. Atomic Force Microscopy images show the DNA bound on the surface of the nanoparticles. The gene delivery and transfection efficiency were analyzed by flow cytometry. These nanoparticles could effectively compact the pDNA, allowing efficient gene transfer into the HeLa cell lines.

Organic Synthesis Using Nitroxides

Nitroxides, also known as nitroxyl radicals, are long-lived or stable radicals with the general structure R1R2N-O•. The spin distribution over the nitroxide N and O atoms contributes to the thermodynamic stability of these radicals. The presence of bulky N-substituents R1 and R2 prevents nitroxide radical dimerization, ensuring their kinetic stability. Despite their reactivity toward various transient C radicals, some nitroxides can be easily stored under air at room temperature. Furthermore, nitroxides can be oxidized to oxoammonium salts (R1R2N═O+) or reduced to anions (R1R2N-O-), enabling them to act as valuable oxidants or reductants depending on their oxidation state. Therefore, they exhibit interesting reactivity across all three oxidation states. Due to these fascinating properties, nitroxides find extensive applications in diverse fields such as biochemistry, medicinal chemistry, materials science, and organic synthesis. This review focuses on the versatile applications of nitroxides in organic synthesis. For their use in other important fields, we will refer to several review articles. The introductory part provides a brief overview of the history of nitroxide chemistry. Subsequently, the key methods for preparing nitroxides are discussed, followed by an examination of their structural diversity and physical properties. The main portion of this review is dedicated to oxidation reactions, wherein parent nitroxides or their corresponding oxoammonium salts serve as active species. It will be demonstrated that various functional groups (such as alcohols, amines, enolates, and alkanes among others) can be efficiently oxidized. These oxidations can be carried out using nitroxides as catalysts in combination with various stoichiometric terminal oxidants. By reducing nitroxides to their corresponding anions, they become effective reducing reagents with intriguing applications in organic synthesis. Nitroxides possess the ability to selectively react with transient radicals, making them useful for terminating radical cascade reactions by forming alkoxyamines. Depending on their structure, alkoxyamines exhibit weak C-O bonds, allowing for the thermal generation of C radicals through reversible C-O bond cleavage. Such thermally generated C radicals can participate in various radical transformations, as discussed toward the end of this review. Furthermore, the application of this strategy in natural product synthesis will be presented.

TiO2 nanoparticles decorated with Co-Schiff base-g-C3N4 as an efficient photocatalyst for one-pot visible light-assisted synthesis of benzimidazoles

In this study, a novel heterogeneous visible light-driven nanocatalyst was produced via the complexation of Co(ii) with g-C₃N₄-imine-functionalized TiO₂ nanoparticles. It was characterized using different techniques such as Fourier-transform infrared (FT-IR), energy-dispersive X-ray spectrum (EDS), inductively coupled plasma atomic emission spectroscopy (ICP-AES), thermogravimetric analysis (TGA), ultraviolet-visible diffuse reflectance spectroscopy (UV-vis DRS), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The catalyst promoted several different transformations in a one-pot reaction sequence: aerobic photooxidation of benzylic alcohols to aldehydes and then the tandem synthesis of benzimidazoles through the dehydrogenative coupling of primary benzylic alcohols and aromatic diamines. The photocatalyst proved to be highly active, robust, selective, and recyclable under organic reaction conditions and provided affordable products with good to high yields. The results proposed that the improved photoactivity predominantly benefits from the synergistic effects of the heterojunction of Co-carbon nitride on TiO₂ nanoparticles. Moreover, this protocol provides standard conditions avoiding undesirable additives and limitations of oxidation methods, and may help to develop a new strategy for the development of photocatalysis based organic transformations.

The Co-g-C₃N₄-imine/TiO₂ nanohybrid promotes different transformations in a one-pot reaction sequence: aerobic photooxidation of benzylic alcohols to aldehydes, and then the tandem synthesis of benzimidazoles.

Visible-Light-Driven Selective Air-Oxygenation of C-H Bond via CeCl3 Catalysis in Water

Visible-light-induced C-H aerobic oxidation is an important chemical transformation that can be applied for the synthesis of aromatic ketones. High-cost catalysts and toxic solvents were generally needed in the present methodologies. Here, an efficient aqueous C-H aerobic oxidation protocol was reported. Through CeCl₃ -mediated photocatalysis, a series of aromatic ketones were produced in moderate to excellent yields. With air as the oxidant, this reaction could be performed under mild conditions in water and demonstrated high activity and functional group tolerance. This method is economical, highly efficient, and environmentally friendly, and it will provide inspiration for the development of aqueous photochemical synthesis reactions.

Tandem Photocatalysis Protocol for Hydrogen Generation/Olefin Hydrogenation Using Pd-g-C3N4-Imine/TiO2 Nanoparticles

An unprecedented visible-light-driven photocatalytic system consisting of Pd nanoparticles stabilized on g-C₃N₄-imine-functionalized TiO₂ nanoparticles was discovered for photoassisted hydrogen generation followed by olefin hydrogenation under mild conditions. The structural integrity of the as-synthesized photocatalyst was corroborated by Fourier transform infrared spectroscopy, X-ray powder diffraction, energy-dispersive X-ray spectroscopy, inductively coupled plasma atomic emission spectroscopy, X-ray photoelectron spectroscopy, ultraviolet-diffuse reflectance spectroscopy, Brunauer-Emmett-Teller measurements, and thermogravimetric analysis (TGA). Transmission electron microscopy and high-resolution scanning electron microscopy revealed the nanoscopic nature of the catalyst. The photocatalyst promoted several different transformations in a one-pot reaction sequence: hydrogen evolution through photocatalytic acceptorless formation of benzimidazoles as important therapeutic agents followed by visible-light-driven photocatalytic reduction of olefins with a high hydrogen utilization efficiency of up to 92% under mild conditions. A significant volume of H₂ was produced under blue light-emitting diode (LED) irradiation during the selective formation of benzimidazole, while the selectivity reduced significantly under a Xe lamp or in the dark. The in situ-generated H₂ could be activated by the as-prepared Pd-C₃N₄-imine/TiO₂ photocatalyst to effectively hydrogenate olefins under mild conditions at appropriate time exposed to blue LED irradiation. The light-dependent photocatalytic performance of the title catalyst was assessed using action spectra by calculating the apparent quantum efficiency (AQE), which exhibited the maximum AQEs at 410 and 550 nm, at which the highest performance for styrene hydrogenation was obtained. The improved photoredox activity of the title nanohybrid could be caused by the synergistic effects of the heterojunction of carbon nitride-Pd on TiO₂ nanoparticles evidenced by photoluminescence spectra and catalytic reactions. The catalyst proved to be air-stable, robust, recyclable, and very active in the absence of any undesirable additives and reducing agents. Thus, this work presents a new protocol for improving the photocatalytic properties of semiconducting materials for various photocatalytic applications under environmentally friendly conditions.

Single-Walled Carbon Nanotube Supported PtNi Nanoparticles (PtNi@SWCNT) Catalyzed Oxidation of Benzyl Alcohols to the Benzaldehyde Derivatives in Oxygen Atmosphere

This study reports a developed process which is a general and facile method for the oxidation of benzyl alcohol (BnOH) compounds to the benzaldehyde (BA) derivatives, under mild conditions. The oxidation of BnOH species catalyzed by PtNi@SWCNT in toluene (3 ml) at 80 °C under a continuous stream of O₂. Single wall carbon nanotube supported PtNi (PtNi@SWCNT) nanoparticles were synthesized using a single-step modified reduction process. The characterization of PtNi@SWCNT nanocatalyst was performed by transmission electron microscope (TEM), X-ray diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), and elemental analysis by ICP-OES. A variety of BnOH compounds were oxidized by the PtNi@SWCNT catalyst and all the expected oxidation products were obtained in high efficiency in 2 hours of reaction time. TLC was used to monitoring the reaction progress, and the products were identified by ¹H/¹³C-NMR analysis.

Metal complex catalysis in the chemistry of lower diamondoids

The review presents the first survey of published data on the use of compounds, complexes and nanoparticles of transition metals (Fe, Co, Ni, Mn, V, Mo, Cu, Pd, Pt, Rh, Ru, Os, Au, Re and Th) in the catalytic transformations of lower diamondoids — adamantane, diamantane and their derivatives. Catalytic halogenation, oxidation, alkylation and cross-coupling reactions are considered, and the formation pathways of C–N, C–S and C–Se bonds in the series of adamantanoids are discussed. Reaction conditions, appropriate catalytic systems and the structures of products are presented.

The bibliography includes 242 references.

A Cooperative Effect in a Novel Bimetallic Mo-V Nanocomplex Catalyzed Selective Aerobic C-H Oxidation

In this study, a new heterobimetallic Mo(VI)-V(V) organosilicon Schiff base complex has been prepared and characterized by different techniques, such as FTIR, Raman, MS, ICP-AES, TGA, and XPS. The bimetallic nanocomplex, revealed by TEM images, showed high oxidation stability and desired activity in the aerobic oxidation of a structurally diverse set of benzylic alcohols in ethanol as a safe solvent. Further, oxidation of benzylic hydrocarbons successfully occurred, producing the target compounds in high yields and excellent selectivities. Our results demonstrated a cooperative effect between Mo(VI) and V(V) as redox active sites in an organosilicon Schiff base framework. A facile and practical reusability of the solid catalyst at the end of the reaction was observed.

Heterogeneous Fenton-like activity of novel metallosalophen magnetic nanocomposites: significant anchoring group effect

Novel magnetically recoverable Fe(iii)- and Mn(iii)salophen complexes were designed for the effective degradation of hazardous organic dyes using a heterogeneous advanced oxidation process.

Synthesis, crystal structure and immobilization of a new cobalt(ii) complex with a 2,4,6-tris(2-pyridyl)-1,3,5-triazine ligand on modified magnetic nanoparticles as a catalyst for the oxidation of alkanes

A new Co(ii) complex with formula [Co(tptz)Cl₂]·2H₂O (tptz = 2,4,6-tris(2-pyridyl)-1,3,5-triazine) has been synthesized and characterized, followed by being supported on modified magnetic nanoparticles as a catalyst for the oxidation of alkanes.

Synthesis of efficient Co and N co-doped carbon catalysts with high surface areas for selective oxidation of ethylbenzene

In this manuscript, Co and N co-doped carbon catalysts with high surface areas were prepared via the pyrolysis of cobalt nitrate and 1,10-phenanthroline monohydrate, using Mg(OH)₂ as a pore former, followed by acid etching.

A dendritic TiO2–Co(ii) nanocomposite based on the melamine catalyzed one-pot aerobic photocatalytic synthesis of benzimidazoles

The nanocrystalline TiO₂ surface modified with cobalt melamine dendrimer amine complex under ultrasonic agitation produced a novel low band-gap photocatalyst (Co(ii)–TD@TiO₂). This catalyst system involves photooxidation of alcohols to aldehydes followed by cyclocondensation with 1,2-phenylenediamine to afford benzimidazoles in one-pot operation with good to excellent yield.

Nickel(ii) riboflavin complex as an efficient nanobiocatalyst for heterogeneous and sustainable oxidation of benzylic alcohols and sulfides

A novel Ni(ii)Rf₂ nanocomplex was prepared, which efficiently oxidizes a wide range of benzyl alcohols and sulfides by employing ideal oxidants in green reaction media.

Selective aerobic benzylic C–H oxidation co-catalyzed by N-hydroxyphthalimide and Keplerate {Mo72V30} nanocluster

The catalytic efficiency of a Keplerate {Mo72V30} nanocapsule in the aerobic benzylic C–H oxidation of alcohols and hydrocarbons was exploited.

A cobalt Schiff base complex on TiO2nanoparticles as an effective synergistic nanocatalyst for aerobic C–H oxidation

A cobalt Schiff base complex on TiO₂nanoparticles possess excellent photocatalytic properties under visible light for the aerobic benzylic C–H oxidation.

Synthesis, magnetism and spectral studies of six defective dicubane tetranuclear {M4O6} (M = NiII, CoII, ZnII) and three trinuclear CdII complexes with polydentate Schiff base ligands

Six defective dicubane face-shared and three trinuclear complexes are synthesized. The magnetic behaviors of Ni^II/Co^II complexes and fluorescence properties of Zn^II and Cd^II are studied.

Efficient and selective green oxidation of alcohols by MOF-derived magnetic nanoparticles as a recoverable catalyst

A magnetic Fe₃O₄@C heterogeneous catalyst derived from MOFs is highly efficient and selective in oxidation of alcohols with neat water and base-free conditions.

Enhanced aqueous oxidation activity and durability of simple manganese(iii) salen complex axially anchored to maghemite nanoparticles

Attachment of simple Mn(iii) salen to functionalized magnetic nanoparticles provided a robust magnetically recoverable nanocatalyst for aqueous oxygenation of various substrates using n-Bu₄NHSO₅.

Aerobic benzylic C–H oxidation catalyzed by a titania-based organic–inorganic nanohybrid

The visible light photocatalytic properties of TiO₂/AA/Co organic–inorganic nanohybrid in the aerobic benzylic C–H oxidation was exploited.

Magnetically separable chicken feathers: a biopolymer based heterogeneous catalyst for the oxidation of organic substrates

Magnetically separable chicken feather nanoparticles were found to be efficient, green and heterogeneous catalyst for selective oxidation of alcohols to carbonyls and sulfides to sulfoxides using t-butyl hydroperoxide (TBHP) as oxidant.

A synergistic effect of a cobalt Schiff base complex and TiO2 nanoparticles on aerobic olefin epoxidation

A cobalt Schiff base complex and TiO₂ nanoparticles exhibited a synergistic effect on the visible-light photocatalytic activity in the aerobic oxidation of various olefins in the absence of reducing agent.