Ferrocene/ β-cyclodextrin based supramolecular nanogels as theranostic systems.

A supramolecular redox responsive nanogel (NG) with the ability to sense cancer cells and loaded with a releasing therapeutic agent was synthesized using hostguest interactions between polyethylene glycol-grafted-β-cyclodextrin and ferrocene boronic acid. Cyclic voltammetry matched with other spectroscopy and microscopy methods provided strong indications regarding host-guest interactions and formation of the NG. Moreover, the biological properties of the NG were evaluated using fluorescence silencing, confocal laser scanning microscopy, and cell toxicity assays.

Electrochemical biosensing based on folic acid-triazine-grafted reduced graphene oxide: a highly selective breast cancer cell sensor.

Based on the results of this research, a new electrochemical sensor has been developed to detect human breast cancer cells (MCF-7). A folic acid (FA)-functionalized triazine-grafted reduced graphene oxide (RGOTrz) was used as the modifier of a glassy carbon electrode (GCE) for application as the sensing element. The composition of the resulting FA-RGOTrz/GCE was investigated using XRD (X-ray diffraction), FT-IR (Fourier-transform infrared) spectroscopy, SEM (scanning electron microscopy) and UV-vis spectroscopy studies.

Simultaneous estimation of rates of DNA damage induced by three important chemotherapy drugs by a novel electrochemical biosensor assisted by chemometric multivariate calibration methods.

In this work, a novel electrochemical biosensor assisted by multivariate calibration methods was developed for simultaneous estimation of rates of DNA damage induced by doxorubicin (DX), daunorubicin (DR) and idarubicin (ID), and also to simultaneous determination of the drugs. A glassy carbon electrode was efficiently modified and used as the biosensing platform. Binding and interactions of DX, DR and ID with DNA were modeled by molecular docking methods, and theoretical information was completed by experimental results.

Silver-filled MWCNT nanocomposite as a sensing element for voltammetric determination of sulfamethoxazole.

Here, we introduce a new electrode based on Silver-filled multi-walled carbon nanotube (Ag-MWCNT) and methyltrioctyl ammonium chloride (MTOAC) for highly sensitive voltammetric measurement of Sulfamethoxazole (SMX). The electrode showed an electrocatalytic activity as it led to the diminution of the overpotential and an increase in peak current for SMX oxidation in a phosphate buffer solution (pH 6.0).

Optimization of a new method for extraction of cyanidin chloride and pelargonidin chloride anthocyanins with magnetic solid phase extraction and determination in fruit samples by HPLC with central composite design.

Here, we are reporting a sensitive, simple and rapid method for the analysis of cyanidin chloride and pelargonidin chloride anthocyanins in cherry, sour cherry, pomegranate and barberry produced in Iran. The analytes were extracted with acetonitrile-hydrochloric acid (1% v/v) mixture under optimized pretreatment conditions. Clean-up of the extract from fruits was conducted by magnetic solid phase extraction using salicylic acid functionalized silica-coated magnetite nanoparticles (SCMNPs) as the adsorbent.

Ultra-trace electrochemical impedance determination of bovine serum albumin by a two dimensional silica network citrate-capped gold nanoparticles modified gold electrode.

In this work, a gold electrode (GE) was modified by coating with two dimensional silica network/citrate capped gold nanoparticles-poly(diallyldimethylammonium chloride) (GE-TDSN-CGNP-PDDA) for ultra-sensitive determination of Bovine Serum Albumin (BSA). After covalently binding of a silica network (in two-dimensional form) on the surface of a gold electrode, via twice in situ hydrolysis of 3-mercaptopropyl-tri-ethoxysilane, citrate capped gold nanoparticles (CGNP) were chemically adsorbed on the silica cage. Subsequently, PDDA was bonded to CGNP via electrostatic interaction of positively charged polymer and negatively charged stabilizer of CGNP.

New bis[N-(4-pyridyl)-P-toluene sulfonamide] palladium dichloride a novel fluorophore for determination of lysine amino acid.

Here, we are describing the study of the chemiluminescence arising from the reaction of bis (2,4,6-trichlorophenyl) oxalate (TCPO) system with new bis [N-(4-pyridyl)-p-toluene sulfonamide] palladium dichloride (BSPC) as a novel luminescent. The optimum concentrations of all reagents such as sodium salicylate (SS) as catalyst, hydrogen peroxide as oxidizing reagent and the relationships between the chemiluminescence intensity and concentrations of TCPO, SS, hydrogen peroxide and BSPC are reported. After optimization the required reagents, the system were used for determination of amino acid lysine, as an effective and selective quencher in the solution functioning in a Stern-Volmer fashion.

Dye doped Eosin yellowish silica nanoparticles as novel fluorophore for a peroxyoxalate chemiluminescence system.

In this work, we report the preparation and characterization of novel dye doped fluorophore Eosin yellowish silica nanoparticles (ESNPs). We synthesized ESNPs by the Stöber method via encapsulation of Eosin Yellowish in silica particles by the condensation of tetraethyl orthosilicate under alkaline condition at room temperature. The resulted ESNPs were characterized by transmission electron microscopy, atomic force microscopy; UV-Visible, fluorescence and Fourier transform infrared spectroscopy.

Sol-gel derived highly selective optical sensor for sensitive determination of the mercury(II) ion in solution.

We report a versatile optical sensor by incorporating the indicator dye 4-phenyl-2,6-bis(2,3,5,6-tetrahydrobenzo[b][1,4,7]trioxononin-9-yl)pyrylium perchlorate into a sol-gel layer. The proposed optical sensor that is stable, fast and highly selective to Hg(2+) ions shows a significant absorbance signal change on exposure to an aqueous solution containing mercury(II) ion. The sensing film is able to determine mercury(II) ion in aqueous solution with a high selectivity over a wide dynamic range between 1.

PVC membrane potentiometric sensor based on 5-pyridino-2,8-dithia[9](2,9)-1,10-phenanthroline-phane for selective determination of neodymium(III).

Spectrofluorometric studies on the binding properties of 5-pyridino-2,8-dithia[9](2,9)-1,10-phenanthrolinephane (L) toward La3+, Sm3+, Gd3+, Yb3+, and Nd3+ in methanol solution revealed the occurrence of both 1:1 and 2:1 (ligand/metal) complexation with a stability order of Nd3+ > Yb3+ > Gd3+ > Sm3+ > La3+. Consequently, L was used as a suitable neutral ionophore for the preparation of a novel polymeric membrane-selective electrode for Nd3+ ion. The electrode exhibited a Nernstian response over a wide concentration range (1.

Fluorometric chemosensors. Interaction of toxic heavy metal ions Pb(II), Cd(II), and Hg(II) with novel mixed-donor phenanthroline-containing macrocycles: spectrofluorometric, conductometric, and crystallographic studies.

The macrocycles L(1)-L(3) incorporating N(2)S(3)-, N(2)S(2)O-, and N(2)S(2)-donor sets, respectively, and containing the 1,10-phenanthroline unit interact in acetonitrile solution with heavy metal ions such as Pb(II), Cd(II), and Hg(II) to give 1:1 ML, 1:2 ML(2), and 2:1 M(2)L complex species, which specifically modulate the photochemical properties of the ligands. The stoichiometry of the complex species formed during spectrofluorometric titrations and their formation constants in MeCN at 25 degrees C were determined from fluorescence vs M(II)/L molar ratio data. The complexes [Pb(L(1))][ClO(4)](2).

A novel crown ether generation containing different heteroaromatic cations: synthesis, characterization, solid-phase (13)C NMR, X-ray crystal structure, and selective amino acid recognition.

The synthesis and structural characterization of a novel generation of crown ethers, 3, 5 and 6 containing pyrilium, thiopyrilium, and pyridinium subunits, respectively, are reported. The crown ether unit is potentially capable of forming host-guest complexes with inorganic and organic cations, while the heteroaromatic cationic unit is suitable to bind with anions. A variety of physicochemical methods including electrospray mass spectrometry, UV-vis spectroscopy, solution and solid-phase NMR, and X-ray crystallography were applied for structural characterization of the new crown ether derivatives.