Chiral separation of three agrochemical toxins enantiomers by high-performance liquid chromatography on a vancomycin crystalline degradation products-chiral stationary phase.

This work aims to evaluate for the enantiomeric separations of three agrochemical toxins: haloxyfop-methyl, fenoxaprop-p-ethyl and indoxacarb on crystalline degradation products-chiral stationary phase (CDP-CSP) of high-performance liquid chromatography (HPLC) under normal and polar organic phases. In the normal phase, the mobile phase was n-hexane with alcohols including methanol and isopropanol as polar modifiers. In the polar organic phase mode, the mobile phase was methanol with different percentages of triethylammunium acetate.

Determination of antioxidant and radical scavenging activity of Basil (Ocimum basilicum L. Family Lamiaceae) assayed by different methodologies.

The antioxidant properties of plants have been investigated, in the light of recent scientific developments, throughout the world due to their potent pharmacological activities and food viability. Basil (Ocimum basilicum L. Family Lamiaceae) is used as a kitchen herb and as an ornamental plant in house gardens.

FT-IR spectrophotometric analysis of coenzyme Q10 (CoQ10) and its pharmaceutical formulations.

A Fourier transform infrared (FT-IR) spectrometric method was developed for the rapid, direct measurement of coenzyme Q10 (CoQ10) in different pharmaceutical products. Conventional KBr spectra were compared for the best determination of active substance in drug preparations. Lambert-Beer's law and two chemometric approaches, partial least squares (PLS) and principal component regression (PCR+) methods, were used in data processing.

Pharmaceuticals analysis by capillary electrophoresis at nanolevel detection.

There is an urgent need to analyze drugs and pharmaceuticals at nanoscale detection, both now and in the future. Capillary electrophoresis is a growing technique that is continuously developing with improved detectors, sample preparation units, and other components. This article describes the analysis of drugs and pharmaceuticals by capillary electrophoresis at nanoscale detection in various standard solutions, dosage formulations, and biological samples.

Simultaneous detection of creatine and creatinine using a sequential injection analysis/biosensor system.

Carbon paste based biosensors for the determination of creatine and creatinine have been integrated into a sequential injection system. Applying the multi-enzyme sequence of creatininase (CA), and/or creatinase (CI) and sarcosine oxidase (SO), hydrogen peroxide has been detected amperometrically. The linear concentration ranges are of pmol/L to nmol/L magnitude, with very low limits of detection.

Antioxidant activity of two wild edible mushrooms (Morchella vulgaris and Morchella esculanta) from North Turkey.

The ethanol extracts of Morchella vulgaris (EEMV) and Morchella esculanta (EEME) were analysed for their antioxidant activities in different systems including reducing power, free radical scavenging, superoxide anion radical scavenging, total antioxidant activity, and metal chelating activity. EEMV and EEME had similar reducing power, free radical scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, and metal chelating activity at concentrations of 50, 100, and 150 microg/mL. These various antioxidant activities were compared to standard antioxidants such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), and alpha-tocopherol.

Evaluation of apoptosis-induction by newly synthesized phthalazine derivatives in breast cancer cell lines.

Newly synthesized phthalazine derivatives including copper and platinum complexes were evaluated for cytotoxicity in human breast cancer cell lines. The cells were incubated with the compounds (100 microM) for 72 h and cytotoxicity, apoptosis and DNA content were measured by flow cytometery. Our results suggest that the parent (H1-2), copper (C1-2)- and platinum (P1-2)-derivatized compounds were relatively more active in inducing apoptosis and cell killing in both human breast cancer cell lines, MDA-MB-231 cells being the more sensitive.

UPLC-MS/MS determination of doxazosine in human plasma.

A sensitive, selective and rapid method for the analysis of doxazosine (DOX) in human plasma based on ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) is described. DOX and tamsulosin, used as an internal standard (IS), were extracted by liquid-liquid extraction, and the chromatography was performed on a C18 UPLC column packed with 1.7 mum particles.

Impact of immobilized polysaccharide chiral stationary phases on enantiomeric separations.

Immobilized polysaccharide-based chiral stationary phases (CSPs) are gaining importance in the resolution of racemic compounds due to their stable nature on working with normal solvents and those prohibited for use with coated phases (tetrahydrofuran, chloroform, dichloromethane, acetone, 1,4-dioxane, ethyl acetate, and certain other ethers). This review discusses the use of immobilized polysaccharide CSPs in the chiral resolution of various racemates by liquid chromatography. The discussion includes immobilization methodologies, enantioselectivities, efficiencies, and a comparison of chiral recognition capabilities of coated vs.

REMOVED: Antioxidant activity of two wild edible mushrooms Morchella vulgaris and Morchella esculenta from north Turkey.

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Combinational numeral fingerprint spectra of Glycyrrhiza and analysis of common peak ratio invariableness in HPLC.

To overcome the instability of traditional Chinese medicine (TCM) fingerprint spectra (FPS) and to build up absolute identification standard of TCM, the construction method of combinational numeral fingerprint spectra (CNFPS) was set up. The analysis of invariableness based on CNFPS was carried out. It can be used as absolute quantitative standard to identify the difference of TCM samples.

Physical activity in the prevention of cancer.

Objective: The purpose of this paper is to update epidemiological research on relations between physical activity and cancer risk, including physical activity measurement and potential mechanisms of prevention of cancer.

Design: Review of recent systematic reviews, meta-analyses and studies on the topic that have been published in the recent literature.

Results: Convincing epidemiological evidence exists that physical activity reduces colon and breast cancers.

Anti-oxidant and pro-oxidant behaviour of bucillamine.

Bucillamine (BUC) is used clinically for the treatment of rheumatoid arthritis. Some of the pharmacological action of BUC has been reported as being dependent on the production of reactive oxygen species (ROS). In this paper the reactivity of BUC with superoxide anion radical (O(2) (*-)) generated from potassium superoxide/18-crown-6 ether dissolved in DMSO, hydroxyl radical (HO(*)) produced in the Cu(2+)-H(2)O(2) reaction, peroxyl radical (ROO(*)) from 2,2'-azobis (2-amidino-propane) dichloride decomposition, and singlet oxygen ((1)O(2)) from a mixture of alkaline aqueous H(2)O(2) and acetonitrile, have been investigated.

Stereoselective HPLC assay of donepezil enantiomers with UV detection and its application to pharmacokinetics in rats.

This investigation describes a new precise, sensitive and accurate stereoselective HPLC method for the simultaneous determination of donepezil enantiomers in tablets and plasma with enough sensitivity to follow its pharmacokinetics in rats up to 12h after single oral dosing. Enantiomeric resolution was achieved on a cellulose tris (3,5-dimethylphenyl carbamate) column known as Chiralcel OD, with UV detection at 268 nm, and the mobile phase consisted of n-hexane, isopropanol and triethylamine (87:12.9:0.

Development and validation of a rapid HPLC method for simultaneous determination of tramadol, and its two main metabolites in human plasma.

Tramadol, an analgesic agent, and its two main metabolites O-desmethyltramadol (M1) and N-desmethyltramadol (M2) were determined simultaneously in human plasma by a rapid and specific HPLC method. The sample preparation was a simple extraction with ethyl acetate. Chromatographic separation was achieved with a Chromolith Performance RP-18e 50 mm x 4.

Rapid determination of haloperidol and its metabolites in human plasma by HPLC using monolithic silica column and solid-phase extraction.

A rapid, sensitive and reproducible HPLC method was developed and validated for the analysis of haloperidol and its three main metabolites in human plasma. The analysis was carried out on a monolithic silica column (Chromolith Performance RP-18e, 100 x 4.6 mm).

Metal ion speciation and capillary electrophoresis: application in the new millennium.

Metal ions are essential for human beings at low concentrations but they are toxic or even carcinogenic at high concentrations. Many metallic ions are found in the environment in different species which are differentiated not only by their physicochemical forms but also by their diverse toxicities with respect to living organisms (speciation). CE has been used for metal ion speciation.

Scavenging of reactive oxygen species by some nonsteroidal anti-inflammatory drugs and fenofibrate.

Ketoprofen and tolmetin are widely used nonsteroidal anti-inflammatory drugs, whereas fenofibrate belongs to a family of hypolipidemic drugs used in the prevention of cardiovascular diseases. The aim of this study was to assess effect of these drugs on reactions generating reactive oxygen species (ROS). The following generators of ROS were used: 18-crown-6/KO(2) dissolved in DMSO as a source of superoxide radical (O(.

Effect of pyrazoloquinoline derivatives on the growth of Leishmania donovani promastigotes.

A screening study was conducted to examine the effect of a series of synthesized pyrazoloquinoline derivatives on the growth of Leishmania donovani promastigotes. Sixteen compounds were tested, ten of which showed an inhibitory effect on the growth of promastigotes. Compound 1 demonstrated potent antileishmanial activity, followed by compounds 3 and 7.

Rapid liquid chromatography-tandem mass spectrometry method for quantification of ziprasidone in human plasma.

A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the determination of ziprasidone (ZIP) in human plasma was developed. ZIP and N-methyl ziprasidone as internal standard (IS) were extracted from alkalinized plasma using tert- butyl methyl ether. Separation was performed isocratically on a C8 column with 90% acetonitrile containing 2 mmol/L ammonium acetate as a mobile phase with a total run time of 2.

Pharmacokinetics of theophylline after administration of suppositories formulation.

Asthma is a public health problem for developed countries. It attacks all age groups but often starts in childhood. Theophylline ethanoate of piperazine in a suppository form is one of the treatments of asthmatic children.

A validated chiral HPLC method for the determination of mebeverine HCl enantiomers in pharmaceutical dosage forms and spiked rat plasma.

A new, precise, simple and accurate HPLC method was developed for the first time to separate and determine mebeverine enantiomers. Enantiomeric resolution was achieved on a cellulose Tris (3,5-dimethylphenyl carbamate) column known as Chiralcel OD, with UV detection at 263 nm. The mobile phase consisted of n-hexane, isopropyl alcohol and triethylamine (90:9.

Quantitative analysis of bucillamine and its pharmaceutical formulation using FT-IR spectroscopy.

A Fourier transform infrared (FT-IR) spectrometric method was developed for the rapid, direct measurement of bucillamine. Conventional KBr-spectra and DRIFTS spectra were compared for best determination of active substance in its tablet formulation. Two chemometric approaches, partial least squares (PLS) and principal component regression (PCR+) methods were used in data processing.

Determination of isoxsuprine hydrochloride by sequential injection visible spectrophotometry.

An automated sequential injection (SI) spectrophotometric method for the determination of isoxsuprine hydrochloride is described. The method is based on the condensation of aminoantipyrine with phenols (isoxsuprine hydrochloride) in the presence of an alkaline oxidizing agent (potassium hexacyanoferrate) to yield a pink colored product, the absorbance of which is monitored at 507 nm. Chemical as well as physical SI parameters that affect the signal response have been optimized in order to get better sensitivity, higher sampling rate and better reagent economy.

Structure-retention relationship in a series of chiral 1,4-disubstituted piperazine derivatives on carbohydrate chiral stationary phases.

New racemic 1,4-disubstituted piperazines chemically named ethyl 2-[(4-pyrimidin-2yl-piperazine-1yl)carbonyl]C3-C5-alkanoates 1-7 were synthesized. The compounds were resolved into enantiomers on cellulose tris(4-methylbenzoate) and amylose tris(3,5-dimethylphenylcarbamate) stationary phases using hexane/propan-2-ol mobile phases. The optimum separation conditions for the compounds were obtained on cellulose tris(4-methylbenzoate) with 5% of 2-propanol in hexane.