Zahra Talebpour

• Alzahra University

To investigate the retention mechanism of N-nitrosodiethanolamine (NDELA) in liquid chromatography, the mobile phase composition was changed on five stationary phases including silica, diol, cyano, amino, and zwitterionic. Afterward, temperature, pH, and buffer concentration effects are studied. Results demonstrate a dual hydrophilic interaction li...

In this paper the binding of noscapine (NOS) as an anticancer drug with poor bioavailability and low solubility with beta and methyl-beta cyclodextrins (β-CD and M-β-CD) as the biocompatible drug carriers were discussed using ultraviolet-visible, fluorescence and nuclear magnetic resonance spectroscopy, as well as molecular docking. The absorption...

Quantifying small amounts of the 17-hydroxyprogesterone in various matrix is crucial for different purposes. In this study, a commercial polydimethylsiloxane stir bar was used to extract hormone from water and urine samples. Analysis was performed by high-performance liquid chromatography using a UV detector. The response surface methodology was us...

Introduction In this work, a polyacrylate polymer was synthesized into a pipette tip containing cotton fibers and used to extract carvedilol from water and urine samples. Methods A high-performance liquid chromatography-ultraviolet detection method was developed, which demonstrated the suitability of the purposed pipette tip micro-solid-phase extr...

Since the outbreak of the COVID-19 pandemic, the use of antiviral and other available drugs has been considered to combat or reduce the clinical symptoms of patients. In this regard, it would be necessary to choose sensitive and selective analytical techniques for pharmacokinetic and pharmacodynamic studies, monitoring of drug concentration in biol...

The rapid global growth of plastic production and waste are harbingers of increasing pollution in terrestrial and marine ecosystems for which safe and effective methods of disposal and degradation must be pursued. In the present study, metabarcoding and culture-based studies have been carried out to provide insights into polyethylene terephthalate...

Analysis of cancer biomarkers in the body fluids is a new method for early detection of illness. However, due to the complex matrices of samples, the application of a pre-treatment method is unavoidable before the final analysis by gas chromatography (GC). Solid-phase microextraction (SPME) is a simple and, promising pre-concentration and separatio...

This research aims at determining some free amino acids in amino acid-based infant formulas and amino acid-modified medical foods for inborn errors of metabolism to prove their quality. A method based on high-performance liquid chromatography and diode array detection was developed and validated. Then, overall uncertainty was estimated by the botto...

An efficient method was proposed for routine analysis of the most widely used detergent enzymes.

Flow distributor located at the beginning of the micromachined pillar array column (PAC) has significant roles in uniform distribution of flow through separation channels and thus separation efficiency. Chip manufacturing artifacts, contaminated solvents, and complex matrix of samples may contribute to clogging of the microfabricated channels, affe...

A vinylpyrrolidone-ethylene glycol dimethacrylate-acrylic acid thin film was prepared on a polypropylene guard and its formulation was optimized for application in thin film microextraction followed by direct solid-state spectrofluorimetry method. The surface morphology, fluorescence property and extraction performance of the thin film were investi...

Zeolitic imidazolate framework-8/polyacrylate monolithic (ZIF-8/PA) polymers have been prepared and optimized as a multifunctional material and used for application in stir bar sorptive extraction technique. The coating of ZIF-8/PA stir bar was characterized by FT-IR, XRD, and SEM techniques in terms of chemical structure, surface morphology, and c...

Adulteration of olive oil with the other cheap oils and fats plays an important role in economics and has nutritional benefits. In this work, metabolite profiling was performed using gas chromatography–mass spectrometry to identify and quantify animal fat (lard) adulteration in vegetable oil (olive oil). Principal component analysis could correctly...

In this study, fabrication of a stir bar sorbent is presented by electropolymerization of pyrrole via cyclic voltametry for the first time. The fabricated stir bar was applied as an efficient sorbent for extraction and pre-concentration of trace amounts of estradiol in urine samples through stir bar sorptive extraction (SBSE) method followed by gas...

Click chemistry is an approach that uses efficient and reliable reactions to bind two molecular building blocks and avoids the formation of byproducts. It has become increasingly used in a variety of analytical chemistry fields, such as electrochemistry, sensor, sample preparation, and separation. In the latter two fields, click chemistry was utili...

Miniaturization of liquid chromatography (LC) is at the leading edge of the research topics and offers a wide range of applications in chemistry, biology, pharmaceutical, clinical diagnosis, and food analysis. The state-of-the-art “lab-on-chip” or “micro-total analysis systems” gathered scientists all over the world to provide systems with the aim...

Fragrances most widely utilize in cosmetics and personal care products. These are known as allergens and emerging organic contaminants that induce the adverse effects on human health. In addition, dealers are tempted to adulterate the products by adding lower cost materials. It is therefore essential to detect fragrances in raw materials, cosmetics...

In our previous work, a new monolithic coating based on vinylpyrrolidone-ethylene glycol dimethacrylate polymer was introduced for stir bar sorptive extraction. The formulation of the prepared vinylpyrrolidone-ethylene glycol dimethacrylate monolithic polymer was optimized and the satisfactory quality of prepared coated stir bar was demonstrated. I...

Method: A modified quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction method followed by a simple isocratic reversed-phase high-performance liquid chromatography was applied to the simultaneous analysis of sodium benzoate (SB) and potassium sorbate (PS) preservatives in some dairy products was developed. Results: At first compari...

Aims: The aim of this study was to isolate a novel yeast strain, evaluate biosurfactant production by the strain and characterize the major product. Methods and results: The strain SAM20, isolated from grass, identified as Sporisorium sp. aff. sorghi based on phylogenetic analyses. The strain produced approximately 32 g l(-1) glycolipid biosurfa...

This study sought to develop a novel method for the trace analysis of N-nitrosodiethanolamine (NDELA) in shampoos inspired by a Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) extraction, followed by an RP-HPLC method with a water-rich mobile phase. To improve the extraction recovery of NDELA and clean-up efficiency of the shampoo matrix,...

The coupling of electrochemistry and capillary electrophoresis may present an interesting approach in the environmental oxidative samples and biological systems. The attractive advantages with respect to new material in chemically modified electrodes and electrode configuration provide a wide scope for the developments of capillary electrophoresis...

The analysis of pesticides in water samples is of primary concern for quality control laboratories due to the toxicity of these compounds and their associated public health risk. A novel analytical method based on stir bar sorptive extraction (SBSE), followed by 31P quantitative nuclear magnetic resonance (31P QNMR), has been developed for simultan...

During a decade and more since its discovery, the emerging physiological roles of ghrelin in mammalian are increasingly being introduced, proposing a critical need for its quantification in biological milieu. Here in, a simple and sensitive single-step method for extraction and quantification of ghrelin in human plasma was developed and validated u...

A poly acrylate-ethylene glycol (PA-EG) thin film is introduced for the first time as a novel polar sorbent for sorptive extraction method coupled directly to solid-state spectrofluorimetry without the necessity of a desorption step. The structure, polarity, fluorescence property and extraction performance of the developed thin film were investigat...

A new monolithic coating based on vinylpyrrolidone-ethylene glycol dimethacrylate polymer was introduced for stir bar sorptive extraction. The polymerization step was performed using different contents of monomer, cross-linker and porogenic solvent, and the best formulation was selected. The quality of the prepared vinylpyrrolidone-ethylene glycol...

Four strains of a novel ascomycetous yeast species were isolated from flowers in Iran and China. Phylogenetic analysis of the ITS region (including 5.8S rDNA) and the LSU rRNA gene D1/D2 domains sequences indicated that these strains belong to the Starmerella clade and show divergence from previously described species in this clade. Growth reaction...

Background and Aim: Sophorolipids are one of the most promising glycolipid biosurfactants produced by yeasts of the genera Starmerella, Wickerhamiella, and Rhodotorula. Methods: A yeast strain, SAM09, was isolated from the flowers of Salsola sp. collected from a desert in East Azerbaijan Province, Iran. Morphological and physiological characteristi...

A gradient high-performance liquid chromatography- photo diode array detection (HPLC-PDA) method applying monolithic RP-C18 column was developed to facilitate the separation amino acid phenylketonuria disorder within 6 min. Phenylalanine (Phe) and tyrosine (Tyr) extracted from dried bloodspot (DBS) and serum protein precipitated by perchloric acid...

In recent years, the need of measurement and detection of samples in situ or with very small volume and low concentration (low sub parts per billion) is a cause for going to miniaturize systems via micro electromechanical system (MEMS) technology. Gas chromatography (GC) is a common technique that is widely used for separating and measuring the sem...

A simple, sensitive and reliable procedure based on stir bar sorptive extraction coupled with high-performance liquid chromatography was applied to simultaneously extract and determine three semi-polar nitrosamines including N-nitrosodibutylamine, N-nitrosodiphenylamine and N-nitrosodicyclohexylamine. To achieve the optimum conditions, the effect o...

A sensitive, selective and simple method for the simultaneous determination of carvedilol enantiomers in aqueous solution has been developed using stir bar sorptive extraction (SBSE) followed by high-performance liquid chromatography (HPLC) with ultraviolet (UV) detection. This method is based on the reaction of carvedilol enantiomers with (-)-ment...

The aim of this paper is to discuss the determination of carbaryl in water sample using a stir bar sorptive extraction method based on a new polar extraction phase coupled with a liquid desorption high performance liquid chromatography-diode array detection (SBSE-LD-HPLC-DAD). The process was conducted in an extraction medium mainly prepared from p...

Sr–Al mixed oxides nanocomposite as Sr3Al2O6 was prepared by sol–gel method and used as a basic heterogeneous catalyst for transesterification of soybean oil to methyl esters (biodiesel) by methanol. The prepared catalyst was characterized using X-ray diffraction (XRD), Transmission electron microscope (TEM), thermogravimetric analysis (TGA/DTA), t...

Background: Tanacetum sonbolii Mozaff. is an endemic species of Tanacetum growing in Iran, west Azerbaijan. The composition of its essential oil can be varied due to conditions of selected extraction method. Thus, the selection of suitable extraction method is very effective to obtaine essential oil in native state. Objective: The purpose of this s...

Cefixime is an important cephalosporin antibiotic that easily decomposes and releases different related substances in preparation and storage steps. The objective of the current study was to develop a simple, precise, and accurate isocratic liquid chromatography (LC) method for the determination of cefixime in the presence of its related substances...

This article presents a method employing stir bar coated with a film of poly (methyl methacrylate/ethyleneglycol dimethacrylate) (PA-EG) and polydimethylsiloxane (PDMS) in combination with liquid desorption (LD) using ionic liquid, followed by high performance liquid chromatography (HPLC) equipped with ultraviolet (UV) detection for the determinati...

This study is designed to examine the chemical composition of the essential oil and antioxidant activities of the different extracts of Tanacetum sonbolii Mozaff. from Iran for the first time. The essential oil was isolated by hydrodistillation and its gas chromatography and gas chromatography-mass spectrometry analyses resulted in the identificati...

Trichlorfon or O,O-dimethyl-(2,2,2-trichloro-1-hydroxyethyl) phosphonate is an organophosphorus insecticide with cholinesterase inhibitor activity that has been widely used in protection of field and fruit crops. Trichlorfon rearranges to other more toxic organophosphate insecticides (such as dichlorvos at pH 6–8) in aqueous media. Trichlorfon is a...

A rapid, direct, and reagent-free procedure based on solid-state Fourier transform infrared spectroscopy (FT-IR) coupled with partial least squares (PLS) data analysis has been developed for simultaneous determination of pyruvate and acetate levels in a microbial xanthan biopolymer. The influences of various spectral pre-processing procedures were...

A rapid, selective, and accurate quantitative ³¹P nuclear magnetic resonance (³¹P NMR) spectroscopy method was used for the chiral recognition of the racemic organophosphorus pesticide fenamiphos using chiral solvating agents (CSAs). Six neutral cyclodextrins (CDs) (α-CD, β-CD, methyl-β-CD, hydroxyethyl-β-CD, hydroxypropyl-β-CD, and hydroxypropyl-γ...

A sensitive and reproducible stir bar sorptive extraction and HPLC-UV detection method was used for the therapeutic drug monitoring of chlorpromazine and trifluoperazine in human serum. The separation was achieved using a C(18) column. The mobile phase consisted of methanol/sodium acetate buffer (pH 4.1; 0.1 M) (95:5, v/v) including 0.5% triethylam...

A novel poly(methyl methacrylate–ethyleneglycol dimethacrylate–acrylic acid) film has been introduced for coating on stir bars to sorptive extraction (SBSE). The effects of different contents of porogen, monomer, cross-linker, modifier and initiator during the solvent or bulk polymerization step on the mechanical property and solvent resistant of p...

In this study, a new method for the simultaneous determination of penicillin G salts in pharmaceutical mixture via FT-IR spectroscopy combined with chemometrics was investigated. The mixture of penicillin G salts is a complex system due to similar analytical characteristics of components. Partial least squares (PLS) and radial basis function-partia...

Background: Rosmarinus officinalis L. (Rosmary) is one of the essential oil containing plants from Lamiaceae family. Rosemary is a native of the Mediterranean region of Europe and the Near East. It has been used as a food spice and as a medicine since ancient times. Today rosemary is cultivated in nearly all countries as a medicinal and ornamental...

In the present study, a microwave-assisted extraction (MAE) method has been investigated for the extraction of glycyrrhizin from Menthazin herbal drug. The extracted samples have been analyzed by a developed reversed-phase liquid chromatography with ultraviolet detection. The separation was performed by a Eurospher-100 C8 reversed-phase column (250...

In this study, pH responsive macroparticles incorporating peppermint oil (PO) were prepared using a simple emulsification/polymer precipitation technique. The formulations were examined for their properties and the desired quality was then achieved using a quality by design (QBD) approach. For this purpose, a Draper-Lin small composite design study...

Microwave assisted extraction (MAE) and ultrasound assisted extraction (UAE) methods were applied for the first time for the extraction of anthocyanins from red grape skins, and the results of these methods were compared with the maceration method. The extracted samples were analyzed by high performance liquid chromatography (HPLC) and nine anthocy...

A high-performance liquid chromatographic (HPLC) method was developed for the determination of N-nitrosodiethanolamine (NDELA), which is a non-volatile N-nitrosoamine. In this method, sodium 1-octanesulfonate has been used as an ion complexation agent for NDELA. The resulting complex was analyzed by reversed-phase high-performance liquid chromatogr...

Microwave‐assisted extraction (MAE) has been applied for extraction of paclitaxel from a cell culture. Solid phase C18 has been used for clean up of the sample obtained from the optimized condition of MAE. The factorial design shows that the temperature and ratio of methanol to water (as an extraction solvent) are effective and extraction time is n...

A selective and rapid 19F NMR spectroscopic analytical procedure for insect growth regulator diflubenzuron, a phenylurea insecticide, has been developed. Optimal NMR sensitivity based upon T1 relaxation time was investigated for diflubenzuron and 4-fluorobenzoic acid as internal standard in dimethyl sulphoxide. The method was validated through spik...

19F nuclear magnetic resonance was used as a suitable analytical tool for the identification and selective determination of haloperidol in human serum and pharmaceutical preparations. The method is based on the integration of appropriate signals of haloperidol and trifluoroacetic acid as an internal standard. The proposed method is a rapid and faci...

Trichlorfon is an organophosphorus insecticide, which is extensively being used for protection of fruit crops. Trichlorfon is a thermal labile compound, which cannot be easily determined by gas chromatography (GC) and has no suitable group for sensitive detection by high performance liquid chromatography (HPLC). In this study, a 31P nuclear magneti...

In this approach, a derivatization method is described for monitoring of organic acids in fermentation media without any separation step. The aqueous phase of fermentation media was evaporated and heated in a silylation reagent to form trimethylsilyl (TMS) derivatives. The silylated compounds are analyzed by 29Si nuclear magnetic resonance (29Si NM...

A simple and rapid microwave-assisted extraction (MAE) procedure was developed and optimized for the extraction of paclitaxel (Taxol) from the needles of yew trees Taxus baccata L. grown in Iranian habitats. The samples, immersed in a methanol-water mixture, were irradiated with microwaves in a closed-vessel system. The method was evaluated using a...

Preliminary theoretical studies revealed the selective complexation of bis (2-mercaptoanil) diacetyl (BMDA) with La3+ over several alkali, alkaline earth and heavy metal ions. Thus, novel PVC-based membrane (PBM) and coated graphite membrane (CGM) sensors for La(III) based on BMDA were prepared. The electrodes display Nernstian behavior over wide c...

Cadmium-113 nuclear magnetic resonance was used as a sensitive probe to study the interaction of Cd2+ ion with 15-crown-5 and benzo-15-crown-5 in acetonitrile and its binary mixtures with water and nitromethane. The observed 113Cd-NMR chemical shift changes at a constant Cd2+ ion concentration and varying crown concentrations were found to be consi...

Preliminary theoretical studies revealed the selective complexation of bis (2-mercaptoanil) diacetyl (BMDA) with La3+ over several alkali, alkaline earth and heavy metal ions. Thus, novel PVC-based membrane (PBM) and coated graphite membrane (CGM) sensors for La(III) based on BMDA were prepared. The electrodes display Nernstian behavior over wide c...

A method utilizing NMR spectroscopy has been developed to confirm the identity and quantity of levodopa, carbidopa and methyldopa in human serum and pharmaceutical preparations. The method is based on 500 MHz proton NMR spectra of individual catecholamine molecules. Qualitative and quantitative analyses are based on resonance characteristics of the...

A 1H NMR method for the simultaneous identification and determination of caffeine and theophylline in pharmaceutical preparations and human serum has been developed. 1H NMR spectrum of caffeine exhibits three sharp singlets at 2.75, 2.93 and 3.40 ppm, while that of theophylline shows two singlet peaks at 2.77 and 2.97 ppm. For the purpose of quanti...

This investigation was carried out to evaluate 19F nuclear magnetic resonance as an analytical tool for the measurement of the cis(Z) and trans(E) stereoisomers of the antipsychotic drug flupentixol in human serum. The method is based on the integration of appropriate signals of both analytes and an internal standard. The proposed method was applie...

Solution studies on the binding properties of 4,5,6,7-tetrathiocino[1,2-b:3,4-b']diimidazolyl-1,3,8,10-tetraethyl-2,9-dithione (Et(4)todit) toward a number of cationic species including some lanthanide ions revealed the occurrence of a selective 1:1 complexation of the ligand with Sm(3+) ion. Consequently, Et(4)todit was used as a suitable neutral...

A 1H-NMR procedure based on an analysis of its data by a multivariate calibration method was conducted for the simultaneous determination of theophylline and caffeine in synthetic and real samples. Partial least squares regression (PLS) was chosen as the calibration method. The methyl signals of theophilline at 3.36 and 3.54 ppm that overlapped wit...

Two different processes for degradation of N-1-naphthylphthalamic acid (naptalam, Nap) are known. Formation of 1-naphthylamine (Na) and phthalic acid (Pha) is one of the degradation processes. Another degradation product of Nap is N-(1-naphthyl) phthalimide (Nad). The HPLC results show that the production of Na and Pha is a major degradation reacti...

Proton NMR was used to study the complexation reaction between silver ion and hexathia-18-crown-6 in a number of binary mixed solvents of dimethyl sulfoxide with acetonitrile and methanol. Formation constants for the resulting 1:1 complexes in different solvent mixtures were determined by computer fitting of the chemical shift-mole ratio data. The...

A 1H NMR procedure for the monitoring of ampicillin (Amp) and its main related substance in different media, has been developed. The characteristics peak of Amp, 6-aminopenicillanic acid (6-APA), phenylglycine (PhG), and penicilloic acid in the range of 0.5-0.9 and 3.0-4.5 ppm were used for their identification in drugs and serum samples. The quant...