Mesoporous Silica with an Alveolar Construction Obtained by Eco-Friendly Treatment of Rice Husks.

The high silicon content in rice plant waste, specifically rice husks, makes this waste by-product attractive for the extraction and valorization of silicon oxide, which is widely used as an inert support in catalysis, drug delivery and molecular sieving. The procedures currently used for the treatment of plant biomass make extensive use of mineral acids (HCl, HSO, HNO), which, besides them being potential environmental pollutants, reduce the yield and worsen the chemical-physical properties of the product. In this study, an evaluation of the easy treatment of rice husks by benchmarking different, more eco-friendly carboxylic acids in order to obtain a mesoporous SiO with an alveolar structure and a relatively high surface area and pore volume (300-420 m/g, 0.

Correction: Popova et al. Ni-Cu and Ni-Co-Modified Fly Ash Zeolite Catalysts for Hydrodeoxygenation of Levulinic Acid to γ-Valerolactone. 2024, , 99.

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Ni-Cu and Ni-Co-Modified Fly Ash Zeolite Catalysts for Hydrodeoxygenation of Levulinic Acid to γ-Valerolactone.

Monometallic (Ni, Co, Cu) and bimetallic (Ni-Co, Ni-Cu) 10-20 wt.% metal containing catalysts supported on fly ash zeolite were prepared by post-synthesis impregnation method. The catalysts were characterized by X-ray powder diffraction, N physisorption, XPS and H-TPR methods.

Pharmacological Activities of Schiff Bases and Their Derivatives with Low and High Molecular Phosphonates.

This review paper is focused on the design of anthracene and furan-containing Schiff bases and their advanced properties as ligands in complex transition metal ions The paper also provides a brief overview on a variety of biological applications, namely, potent candidates with antibacterial and antifungal activity, antioxidant and chemosensing properties. These advantageous properties are enhanced upon metal complexing. The subject of the review has been extended with a brief discussion on reactivity of Schiff bases with hydrogen phosphonates and the preparation of low and high molecular phosphonates, as well as their application as pharmacological agents.

Novel Electrospun Composite Membranes Based on Polyhydroxybutyrate and Poly(vinyl formate) Loaded with Protonated Montmorillonite for Organic Dye Removal: Kinetic and Isotherm Studies.

The use of biodegradable polyesters derived from green sources and their combination with natural abundantly layered aluminosilicate clay, e.g., natural montmorillonite, meets the requirements for the development of new sustainable, disposable, and biodegradable organic dye sorbent materials.

Engineering of Silica Mesoporous Materials for CO Adsorption.

Adsorption methods for CO capture are characterized by high selectivity and low energy consumption. Therefore, the engineering of solid supports for efficient CO adsorption attracts research attention. Modification of mesoporous silica materials with tailor-made organic molecules can greatly improve silica's performance in CO capture and separation.

Curcumin and Capsaicin-Loaded Ag-Modified Mesoporous Silica Carriers: A New Alternative in Skin Treatment.

Biologically active substances of natural origin offer a promising alternative in skin disease treatment in comparison to synthetic medications. The limiting factors for the efficient application of natural compounds, such as low water solubility and low bioavailability, can be easily overcome by the development of suitable delivery systems. In this study, the exchange with the template procedure was used for the preparation ofa spherical silver-modified mesoporous silica nanocarrier.

Nematic-to-Isotropic Phase Transition in Poly(-Lactide) with Addition of Cyclodextrin during Abiotic Degradation Study.

Poly(-lactide) is capable of self-assembly into a nematic mesophase under the influence of temperature and mechanical stresses. Therefore, subsequent poly(-lactide) films were obtained and characterized, showing nematic liquid crystal properties both before and after degradation. Herein, we present that, by introducing β-cyclodextrin into the polymer matrix, it is possible to obtain a chiral nematic mesophase during pressing, regardless of temperature and time.

CO Adsorption on the N- and P-Modified Mesoporous Silicas.

SBA-15 and MCM-48 mesoporous silicas were modified with functionalized (3-aminopropyl)triethoxysilane (APTES) by using the post-synthesis method, thus introducing N- and P-containing groups to the pore surface. The structure of the newly synthesized modifiers (aldimine and aminophosphonate derivatives of (3-aminopropyl)triethoxysilane and their grafting onto the porous matrix were proved by applying multinuclear NMR and FTIR spectroscopies. The content of the grafted functional groups was determined via thermogravimetric analysis.

Hydrodemethoxylation/Dealkylation on Bifunctional Nanosized Zeolite Beta.

Mono-, and bimetallic Ni-, Ru-, and Pt-modified nanosized Beta zeolite catalysts were prepared by the post synthesis method and characterized by powder X-ray diffraction (XRD), nitrogen physisorption, HRTEM microscopy, temperature-programmed reduction (TPR-TGA), ATR FT-IR spectroscopy, and by solid-state MAS-NMR spectroscopy. The presence of nanosized nickel-oxide, ruthenium-oxide, and platinum species was detected on the catalysts. The presence of Brønsted and Lewis acid sites, and incorporation of nickel ions into zeolite lattice was proven by FT-IR of adsorbed pyridine.

Selective Production of Phenol on Bifunctional, Hierarchical ZSM-5 Zeolites.

Mono- and bimetallic Ni-, Ru- and Pt-modified hierarchical ZSM-5 materials were prepared by impregnation technique and characterized by X-ray diffraction (XRD), N physisorption, temperature-programmed reduction (TPR-TGA), ATR-FTIR and solid state NMR spectroscopy. Formation of finely dispersed nickel, ruthenium and platinum species was observed on the bimetallic catalysts. It was found that the peculiarity of the used zeolite structure and the modification procedure determine the type of formed metal oxides and their dispersion and reducibility.

Tamoxifen Delivery System Based on PEGylated Magnetic MCM-41 Silica.

Magnetic iron oxide containing MCM-41 silica (MM) with ~300 nm particle size was developed. The MM material before or after template removal was modified with NH- or COOH-groups and then grafted with PEG chains. The anticancer drug tamoxifen was loaded into the organic groups' modified and PEGylated nanoparticles by an incipient wetness impregnation procedure.

Antimicrobial Activity of Hybrid Nanomaterials Based on Star and Linear Polymers of ,'-Dimethylaminoethyl Methacrylate with In Situ Produced Silver Nanoparticles.

Well-defined linear and multi-arm star polymer structures were used as the templates for in situ synthesis and stabilization of silver nanoparticles (AgNPs). This approach led to hybrid nanomaterials with high stability and antibacterial activity to both Gram-positive and Gram-negative bacterial strains. The ecologically friendly so called "green" synthesis of nanomaterials was performed through AgNPs preparation in the aqueous solutions of star and linear poly(,'-dimethylaminoethyl methacrylate)s (PDMAEMAs); the process was followed with time.

Verapamil delivery systems on the basis of mesoporous ZSM-5/KIT-6 and ZSM-5/SBA-15 polymer nanocomposites as a potential tool to overcome MDR in cancer cells.

ZSM-5/KIT-6 and ZSM-5/SBA-15 nanoparticles were synthesized and further modified by a post-synthesis method with (CH)SOH and (CH)NHCO(CH)COOH groups to optimize their drug loading and release kinetic profiles. The verapamil cargo drug was loaded by incipient wetness impregnation both on the parent and modified nanoporous supports. Nanocarriers were then coated with a three-layer polymeric shell composed of chitosan-k-carrageenan-chitosan with grafted polysulfobetaine chains.

Polyphosphoester-based Paclitaxel Complexes: Biological Evaluation.

Background: Polymer drug delivery systems designed to reduce systemic side-effects are clinically important. Polyphosphoesters are biodegradable polymers with versatile structure that could afford reactive sites or polar functions for drug immobilization.

Materials And Methods: The drug-polyphosphester systems were characterized by nuclear magnetic resonance and infrared spectroscopy, differential scanning calorimetry and dynamic light scattering.

Hybrid protein-synthetic polymer nanoparticles for drug delivery.

Among the most common nanoparticulate systems, the polymeric nanocarriers have a number of key benefits, which give a great choice of delivery platforms. Nevertheless, polymeric nanoparticles possess some limitations that include use of toxic solvents in the production process, polymer degradation, drug leakage outside the diseased tissue, and polymer cytotoxicity. The combination of polymers of biological and synthetic origin is an appealing modern strategy for the production of novel nanocarriers with unprecedented properties.

Polymer complex of WR 2721. Synthesis and radioprotective efficiency.

Polymer complex constructed from WR 2721 and poly(hydroxyoxyethylene phosphate) was synthesized. The structure of complex formed was elucidated by (1)H-, (13)C, (31)P NMR and FT-IR spectroscopy. The radioprotector was immobilized via ionic bonds.

Polyphosphoester conjugates of dinuclear platinum complex: synthesis and evaluation of cytotoxic and the proapoptotic activity.

Macromolecular conjugates of a dinuclear platinum complex with a spermidine bridge were synthesized using poly(oxyethylene H-phosphonate)s as precursor polymer. The complex species were attached to the polymer chain via a phosphoramide bond resulting from the reaction between the H-phosphonate groups and the middle amino group of the spermidine moiety. (1)H and (31)P{H} DOSY NMR spectral data were used to prove the conjugation reaction and to characterize the new species.

Reversibly PEGylated nanocarrier for cisplatin delivery.

A star-shaped copolymer bearing a shell of poly(ethylene glycol) (PEG) chains was designed as a carrier of cisplatin. The proposed strategy was based on synthesis of a PEGylating agent and the incorporation of cisplatin as a reversible linker for PEG modification of the star macromolecules. The attachment of PEG chains to the stars and their release under physiological conditions, as well as the changes in particle size and mobility upon drug loading, was evidenced by diffusion ordered NMR spectroscopy (DOSY).

Characterisation of different nanoparticles with a potential use for drug delivery in neuropsychiatric disorders.

Objectives: Nanoparticles are promising tools for targeted delivery of drugs in the treatment of different diseases, including neuropsychiatric disorders. However, they need to be carefully characterised for any adverse effects which may occur in their presence. In this study, we evaluated the applicability of nanoparticles that belong to three different groups: (i) aggregates from amphiphilic diblock copolymers composed of poly(2-ethyl-2-oxazoline) (PEtOx) and poly(2-phenyl-2-oxazoline) (PPhOx) in different ratios, (ii) stabilised polymeric micelles (SPM) based on poly(ethylene oxide)-b-poly(propylene oxide)-bpoly(ethylene oxide) (PEO-PPO-PEO) and (iii) star-like polymer with poly(acrylic acid) arms and branched polystyrene interior (PSPAA).

Sonochemically born proteinaceous micro- and nanocapsules.

The use of proteins as a substrate in the fabrication of micro- and nanoparticulate systems has attracted the interest of scientists, manufactures, and consumers. Albumin-derived particles were commercialized as contrast agents or anticancer therapeutics. Food proteins are widely used in formulated dietary products.

Star-shaped nano-conjugates of cisplatin with high drug payload.

Core-shell type star polymer bearing carboxylate functions was designed and evaluated as nanocarrier of cisplatin. The synthetic route to the star macromolecules involved the "core first" method to yield a precursor star polymer with a highly branched poly(styrene) core and poly(tert-butyl acrylate) arms. Two polymers derived from a common core of M(n) = 2400 g/mol and degrees of polymerization of the linear arms 38 and 58 were subjected to acidic hydrolysis to obtain stars with a hydrophilic and multifunctional shell.

HPLC study on the stability of bendamustine hydrochloride immobilized onto polyphosphoesters.

Novel water soluble polymer complexes of bendamustine hydrochloride, a bifunctional alkylating agent with antimetabolic and cytotoxic activity, were developed using biodegradable polymer carriers-poly(oxyethylene H-phosphonate), poly(methyloxyethylene phosphate) and poly(hydroxyoxyethylene phosphate). Bendamustine hydrochloride was immobilized onto polyphosphoesters via covalent, ionic and hydrogen bonding. The structure of the complexes formed was elucidated by (1)H, (13)C, (31)P NMR and FT-IR spectroscopy.