Bioactive sesquiterpene lactone from Artemisia santolina

Most species of genus Artemisia L. (Compositae) are medicinal herbswith several uses in the folk medicine worldwide. In the present study, methanol extract of Artemisia santolina has been subjected for isolation of its metabolites along with evaluation of cytotoxic activity against Artemia salina larvae. The structures of the compounds determined by 1H-and 13C-NMR, HMQC, HMBC, 1H-1H COSY and Mass spectral analysis. Two sesquiterpenes, 1,5-dihydroxy- 4(15)eudesman-12,6-olid (artemin) (1), 2-hidroxy-2,6,10-trimethyl-7,10- oxide-3,11-dodecadien-5-one (2) and one flavonoid, 5,7,4'-trihydroxy-6,3'-dimethoxyflavone (jaceosidin) (3) have been successfully characterized. Cytotoxicity of the sesquiterpene lactone (1), was assessed on Artemia salina larvae and resulted in IC50 value of 6.44 μg/mL, which was more potent compared to the positive standard berberine hydrochloride (IC50 = 26 μg/mL). In this study, the separation and identification of two sesquiterpenes and one flavone from the aerial parts of A. santolina is described. Among them the compound artemin (1) showed a toxicity effect against A. salina nauplii

Comparative metal ion extraction of Ag(I), Cu(II), Ni(II), Zn(II), Mn(II), Cd(II) and Co(II) cations using dibenzo 18C6 as a carrier

The competitive metal ion extraction of Ag(I), Cu(II), Ni(II), Zn(II), Mn(II), Cd(II) and Co(II) cations were examined and compared each with other. The experiments were buffered (acetic acid/sodium acetate and formic acid/sodiumformate) at pH 4–6. The extraction of Cu(II) and Ag(I) and Co(II) with Dibenzo 18 crown 6 (DB18C6) ligand is possible, but the extraction efficiency for Ag(I) is much better than Cu(II) and Co(II) ion. The concentrations in the all experiments for the cations and ligand were 0.01 M and 1.0 × 10−3 M respectively. Organic phase employed chloroform, dichloromethane and 1,2dichloroethane in individual experiments. The effect of picric acid in aqueous phase to the efficiency of extraction was investigated. The effect of extraction time, rate of shaking, concentration of ligand and presence of picric acid were investigated and optimized

Multivariate optimization of mebeverine analysis using molecularly imprinted polymer electrochemical sensor based on silver nanoparticles

Thin film of a moleculary imprinted polymer (MIP) based on electropolymerization method with sensitive and selective binding sites for mebeverine (MEB) was developed. This film was cast on pencil graphite electrode (PGE) by electrochemical polymerization in solution of pyrrole (PY) and template MEB via cyclic voltammetry scans and further electrodeposition of silver nanoparticles (AgNPs). Several parameters controlling the performance of the silver nano particles MIP pencil graphite electrode (AgNPs-MIP-PGE) including concentration of PY(mM) concentration of mebeverine (mM), number of cycles in electropolymerization, scan rate of CV process (mV. s−1), deposition time of AgNPs on to the MIP surface (s), stirring rate of loading solution (rpm), electrode loading time (min), pH of Britton–Robinson Buffer (BRB) solution were examined and optimized using multivariate optimization methods such as Plackett–Burman design (PBD) and central composite design (CCD). Two dynamic linear ranges of concentration for the MIP sensor were obtained as. 1 × 10 −8 to 1 × 10 −6 and 1 × 10 −5 to1 × 10−3 M with the limit of detection (LOD) of 8.6 × 10 −9M (S/N = 3). The proposed method was successfully intended for the determination of MEB in real samples (serum, capsule). The sensor was showed highly reproducible response (RSD 1.1%) to MEB concentration. Keywords: Molecularly imprinted polymer, Electrochemical sensor, Mebeverine, Multivariate optimization, Silver nanoparticl

Selective transport of Ag (I) ion across a bulk liquid incorporated with dibenzo 18-crown-6 (DB18C6) as carrier

The competitive metal ion transport of Ag(I), Co(II), Ni(II), Zn(II), Cu(II), Cd(II) and Mn(II) cations with dibenzo-18-crown-6 (DB18C6) were studied and compared. The source phase contained equimolar concentration of the metal cation and the organic phase contained the ligand (DB18C6) in an organic solvent. The concentrations in the all transport experiments for the cations and ligand were 0.01 M and 1.0×10-3 M, respectively. The source phase solutions were buffered (acetic acid/sodium acetate) at pH 4-6. The transports of Cu(II), Ag(І) and Co(II) with DB18C6 are possible in the mixture, but the transport efficiency for Ag(І) ion is much better than the other cations. The presence of dichloromethane and 1,2 dichloroethane were optimized in the organic phase. The results show the transport efficiency depends to the types of thiourea and potassium thiocyanate ligands in the receiving phase. The results show that the presence of palmetic acid in the membrane phase improves the efficiency of the transport for Ag(І) cation

Conductometric Study of Complex Formation Between Cu(II) Ion and 4-Amino-3-ethyl-1,2,4- triazol-5-thione in Binary Ethanol / Water Mixtures

Abstract: The stability constant, K f , for the complexation of copper(II) ion with 4-amino-3-ethyl-1,2,4-triazol-5-thione (AETT ) in 0, 20, 40, 60 and 80 (v/v) % ethanol-water mixtures were determined conductometrically at different tempratures. Stability constant of resulting 1:1 complexes were being larger by increasing of temprature and ethanol percent. Stability constants of complexes vary inversly with dielectric constant of solvents. The enthalpy and entropy of complexation were determined from the temprature dependence of the formation constant. In all cases, the complexation were found to be enthalpy unstablized but entropy stablized. ∆G 0 of the studied complexes were evaluated at 25 0 C using thermodynamic relations, the negative values of ∆G 0 means that the complexation process is spantaneously

Spectrophotometric study of complex formation between iodoquinol (IQ) and Co2+, Mn2+, Cd2+, Pb2+, and Zn2+ in DMF/MeOH binary mixed solvents

The stability constants for complexes of metal ions (M2+) such as Co2+, Mn2+, Cd2+, Pb2+, and Zn2+ with iodoquinol (IQ) at the ionic strength of 0.1 (using NaNO3) have been determined at 25 °C. This study has been done in the binary mixed solvents N,N-dimethyl formamide/Methanol (DMF/MeOH) by a spectrophotometry method. The stoichiometry for M2+/IQ complexes was calculated by applying the “Job” and “molar ratio” methods. A 1:1 complex is generated between each M2+ and the IQ. It was found that the stability constants of the complexes were increased with increasing amount of MeOH in the binary mixtures. The results show that the stability constants decrease in the order Zn2+ > Co2+ > Pb2+ > Mn2+ > Cd2+. The biggest stability constant was found for the Zn2+/IQ system

Study of some alcohol amounts in commercial alcoholic disinfectant solutions using gas chromatography with flame ionization detection

A simple solvent extraction method was used to analyze alcohol-based hand rubs (ABHRs) using gas chromatography with a flame ionization detector. 79 samples including 68 liquid and 11-gelled ABHRs were analyzed in the Food and Drug Laboratories Research Center of Mashhad, Iran. 17 samples had methanol, 50 samples had the correct percentage of alcohol (60-80%), and 12 samples had the incorrect percentage of alcohol (<60%). The RSD% of methanol, ethanol, and isopropanol were as 2.28, 2.18, and 1.52, respectively. The relative recoveries for methanol, ethanol, and isopropanol were 102.5, 97.8, and 114, respectively. All experiments were repeated three times. The limit of detection and the limit of quantification for methanol, ethanol, and isopropanol were obtained as 0.22, 0.24, 0.10 (%) and 0.71, 0.82, 0.68 (%), respectively

Melamine Recognition: Molecularly Imprinted Polymer for Selective and Sensitive Determination of Melamine in Food Samples

In this study, a sensitive and selective sensor is constructed to measure the melamine (MEL) using molecular imprinting polymer (MIP) technique. Chemical and electrochemical techniques are used to construct the MIP and quantitative measurements. The constructed sensor was modified with GO-Fe3O4@SiO2 nanocomposite. Screening and optimization of factors are done using statistical methods, including Plackett–Burman design (PBD) and central composite design (CCD). Under the optimized conditions, an MIP sensor showed a linear range from 5.0 × 10−7 to 1.0 × 10−5 M MEL concentration with a correlation coefficient (R2) of 0.9997. The limit of detection was obtained (0.028 µM) with a highly reproducible response (RSD 2.15%, n = 4). The electrochemical sensor showed good results for the determination of MEL in food samples