Polymer grafted-magnetic halloysite nanotube for controlled and sustained release of cationic drug.

In this research, novel polymer grafted-magnetic halloysite nanotubes with norfloxacin loaded (NOR-MHNTs) and controlled-release, was achieved by surface-initiated precipitation polymerization. The magnetic halloysite nanotubes exhibited better adsorption of NOR (72.10mgg) compared with the pristine HNTs (30.

Antimicrobial activity of aqueous extracts from four plants on bacterial isolates from periodontitis patients.

Four aqueous extracts of different plant organs are the following: Artemisia herba-alba, Opuntia ficus-indica, Camellia sinensis and Phlomis crinita were evaluated against two bacterial strains: Porphyromonas gingivalis and Prevotella intermedia, which are implicated in periodontal diseases. By using a disc method, these plant extracts demonstrated powerful bacterial activity against these Gram-negative strains. The minimum inhibitory concentration values of the four plant extracts varied between 0.

Adsorptive removal of trace sulfonamide antibiotics by water-dispersible magnetic reduced graphene oxide-ferrite hybrids from wastewater.

A one-pot solvothermal synthesis method was developed to prepare reduced graphene oxide (RGO) supported ferrite hybrids using graphite oxide and metal ions (Fe(3+)) as starting materials. The as-prepared composites were characterized by transmission electron microscopy(TEM), Fourier transform infrared spectrophotometer (FT-IR), X-ray powder diffraction pattern(XRD) and vibrating sample magnetometer (VSM). It was shown that Fe3O4 nanoparticles with a uniform size of ∼35nm were anchored on RGO nanosheets.

Mixed hemimicelles solid-phase extraction of cephalosporins in biological samples with ionic liquid-coated magnetic graphene oxide nanoparticles coupled with high-performance liquid chromatographic analysis.

A novel mixed hemimicelles solid phase extraction based on magnetic graphene oxide (Fe3O4/GO) and ionic liquid (IL) was developed for the simultaneous extraction and determination of trace cephalosporins in spiked human urine. The high surface area and excellent adsorption capacity of the graphene oxide after modification with1-hexadecyl-3-methylmidazoliumbromide(C16mimBr) were utilized adequately in the solid phase extraction(SPE) process. A comprehensive study of the parameters affecting the extraction recovery, such as the zeta-potential of magnetic graphene oxide, amounts of magnetic graphene oxide and surfactant, pH of solution, ionic strength, extraction time, and desorption condition were optimized.

Carbon nanotubes: applications in pharmacy and medicine.

Carbon nanotubes (CNTs) are allotropes of carbon, made of graphite and constructed in cylindrical tubes with nanometer in diameter and several millimeters in length. Their impressive structural, mechanical, and electronic properties are due to their small size and mass, their strong mechanical potency, and their high electrical and thermal conductivity. CNTs have been successfully applied in pharmacy and medicine due to their high surface area that is capable of adsorbing or conjugating with a wide variety of therapeutic and diagnostic agents (drugs, genes, vaccines, antibodies, biosensors, etc.

Anticancer loading and controlled release of novel water-compatible magnetic nanomaterials as drug delivery agents, coupled to a computational modeling approach.

The preparation, characterization and application of novel anticancer "epirubicin" (EPI) water-compatible magnetic molecularly imprinted polymers (M-MIPs) like artificial antibodies by computational design and chemical synthesis as a carrier for drug delivery is described herein. Two monomers: methacrylic acid (MAA) and methacrylamide (MAM) were selected by computational simulation from the four chemicals used. Covalent and non-covalent bonds were evaluated by this technique based on the interaction mode and energy with template or solvent.

Development of novel amphiphilic magnetic molecularly imprinted polymers compatible with biological fluids for solid phase extraction and physicochemical behavior study.

In the present work, a novel amphiphilic magnetic molecularly imprinted polymer (M-MIP) has been synthesized by a simple non covalent method for the loading of gatifloxacin (GTFX) in polar solvent. This nanomaterial used as sorbent has been applied to the solid phase extraction of GTFX in different spiked biological fluids. For the first time, studies of dispersibility and solubility behaviors with different solvents and water were performed to demonstrate amphiphilicity and also to find the better nanomaterial obtained.

Adsorption behavior of pazufloxacin mesilate on amino-functionalized carbon nanotubes.

In this study, the interaction between amino-functionalized multi-walled carbon nanotubes (e-MWNTs) and antibacterial agents was investigated and the drug-loading ability of e-MWNTs was evaluated. The e-MWNTs were prepared and characterized, then were used as adsorbents for loading an antibacterial agent, pazufloxacin mesilate (PZFX). The adsorption behavior of PZFX on e-MWNTs in water was investigated.

Molecularly imprinted stationary phase prepared by reverse micro-emulsion polymerization for selective recognition of gatifloxacin in aqueous media.

A new stationary phase for selectively recognizing gatifloxacin in aqueous media based on molecularly imprinted microspheres (MIMs) has been prepared by water/oil reverse micro-emulsion polymerization. The MIMs were prepared using gatifloxacin as the template, N, N'-methylenebisacrylamide as cross-linker and acrylamide and acryloyl-β-CD (β-CD-A, synthesized by ester reaction of acrylic acid with β-CD) as combinatorial functional monomers. The surface morphology of MIMs was characterized by scanning electron microscopy.

Adsorption behavior of epirubicin hydrochloride on carboxylated carbon nanotubes.

The aim of this study was to understand the interaction between carboxylated carbon nanotubes (c-CNTs) and anticancer agents and evaluate the drug-loading ability of c-CNTs. We prepared carboxylated multi-walled carbon nanotubes (c-MWNTs) with nitric acid treatment, then evaluated the adsorption ability of c-MWNTs as adsorbents for loading of the anticancer drug, epirubicin hydrochloride (EPI), and investigated the adsorption behavior of EPI on c-MWNTs. Unmodified multi-walled carbon nanotubes (MWNTs) and single-walled carbon nanotubes (SWNTs) were included as comparative adsorbents.

[Fluorescence study on the interactions between carbon nanotubes and bovine serum albumin].

As a new family of nanomaterials, carbon nanotubes (CNTs) exhibit unique properties such as their capacity to penetrate into the cells and low immunogenicity, which have attracted increasing attention in biomedical field and make their application in drug and gene transfer systems being possible. So getting more information about the interaction of CNTs with biomacromolecules is crucial for further investigation of CNTs in therapeutic applications. The interaction between CNTs and BSA under physiological condition was investigated by fluorescence quenching, synchronous fluorescence and red edge excitation shift (REES)method.

[Fluorescence study on the interactions between G3.0 PAMAM dendrimers and bovine serum albumin].

The interaction between amine terminated G3.0 PAMAM dendrimers and bovine serum albumin (BSA) under physiological condition was studied by fluorescence spectroscopy. Our experiments demonstrated that the fluorescence intensity of BSA decreased after the addition of G3.

Free radicals, antioxidants in disease and health.

Free radicals and oxidants play a dual role as both toxic and beneficial compounds, since they can be either harmful or helpful to the body. They are produced either from normal cell metabolisms in situ or from external sources (pollution, cigarette smoke, radiation, medication). When an overload of free radicals cannot gradually be destroyed, their accumulation in the body generates a phenomenon called oxidative stress.

[Fluorescence characteristic of terbium-ciprofloxacin complex and its application].

On binding to deoxyribonucleic acid, the complex of terbium-ciprofloxacin (Tb(3+)-CIP) increases its fluorescence quantum efficiency. Based on this, an easy, rapid and sensitive method for the determination of DNA was developed. Like ethidium bromide (EB), the complex can be intercalated into DNA bases, but it is non-poisonous.

[Study on the interaction of lomefloxacin terbium complex and bovine serum albumin by fluorescence spectra].

Using lomefloxacin-terbium as a fluorescent probe, the interaction of LFLX-Tb3+ and bovine serum albumin (BSA) was investigated by fluorescence spectra. The interaction of LFLX and BSA is quite strong. LFLX can affect the conformation of BSA to some degree.

In vitro assessment of renal toxicity and inflammatory events of two protein phosphatase inhibitors cantharidin and nor-cantharidin.

In China, cantharidin has been reported to be active against various human cancers, but with severe side effects such as nephrotoxicity. In order to reduce this toxicity, its demethylated analogue nor-cantharidin has been synthesized and used in cancer therapy, but with only few data regarding safety assessment. The aim of this study was to compare the in vitro effects of cantharidin and nor-cantharidin on renal toxicity and on inflammatory events associated with tumoural process where protein phosphatases could be involved (energy status, prostanoid production, glutathione and nitrite contents) on RAW 264.

Solid-phase extraction of methadone enantiomers and benzodiazepines in biological fluids by two polymeric cartridges for liquid chromatographic analysis.

The aim of this work was to present the advantages of two polymeric cartridges (Oasis HLB from Waters and Abselut Nexus from Varian) for the solid-phase extraction of methadone enantiomers and its major metabolite, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) and of some benzodiazepines (diazepam, flunitrazepam, nitrazepam, oxazepam) in serum and urine in comparison with classical C18-bonded-silica cartridges or liquid extraction. After addition of serum or urine samples, these two cartridges were washed with a water-methanol mixture (95:5, v/v) and eluted with diethylether. After rapid evaporation, the residue was regenerated with mobile phase and injected either in a chiral column (Cyclobond I-2000 RSP) for methadone enantiomers and its metabolite or in a reversed-phase column (Symmetry Shield RP8) for benzodiazepines.

Effect of temperature on enantiomer separation of oxzepam and lorazepam by high-performance liquid chromatography on a beta-cyclodextrin derivatized bonded chiral stationary phase.

A reversed-phase high-performance liquid chromatography (HPLC) method with beta-cyclodextrin (beta-CD) derivatized as chiral stationary phase is used to directly separate oxazepam (Oxa) and lorazepam (Lor) enantiomers. The effect of temperature on the direct HPLC separation of Oxa and Lor enantiomers is studied for the commercially available beta-CD derivatized bonded chiral stationary phase. Chromatographic peak coalescence, appearing as a plateau between the resolved peaks, is observed at column temperatures of above 13 degrees C.

Separation of oxazepam, lorazepam, and temazepam enantiomers by HPLC on a derivatized cyclodextrin-bonded phase: application to the determination of oxazepam in plasma.

The enantioselective high-performance liquid chromatography (HPLC) of three racemic 3-hydroxybenzodiazepines, oxazepam (Oxa), lorazepam (Lor), and temazepam (Tem), is a difficult operation because of the spontaneous chiral inversion in polar solvent. To solve this problem, we have developed an HPLC method based on a chiral Cyclobond I-2000 RSP column, maintained at 12 degrees C, and a reversed mobile phase (acetonitrile in 1% triethylamine acetate buffer, TEAA) at a flow rate of 0.4 ml/min.