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Analytical and Bioanalytical Chemistry Research - Volume:6 Issue: 2, Summer-Autumn 2019

Analytical and Bioanalytical Chemistry Research
Volume:6 Issue: 2, Summer-Autumn 2019

  • تاریخ انتشار: 1398/06/18
  • تعداد عناوین: 18
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  • Ali Poormohammadi, Abdulrahman Bahrami *, Balendu Shekher Giri Pages 253-269
    Human exposures to volatile organic compounds (VOCs) are associated with a wide range of health problems. Due to these adverse effects of VOCs on the human health, determination of trace levels of VOCs is very important for accurate assessment of indoor and outdoor exposure. Solid phase microextraction (SPME), needle trap device (NTD) and hollow fiber- liquid phase microextraction (HF-LPME) are increasingly used for accurate determination of VOCs in air. In this paper, authors have reviewed new developed forms of SPME, NTD and LPME techniques for the sampling and analysis of VOCs in air with a main focus on SPME coating fibers and NTD sorbents. The effects of some environmental and device parameters on SPME and NTD samplers are also reviewed. Moreover, several analytical parameters such as carryover effect, storage time, limit of detection (LOD) and limit of quantitation (LOQ) of these new technologies are discussed. Finally, the applicability, limitations and future trends of these methods are reviewed.
    Keywords: Volatile organic compounds (VOC), Solid phase microextraction (SPME), Needle trap device (NTD), Air
  • Somayeh Heydari *, Mohadeseh Hosseinpoor Zaryabi, Hamideh Ghiassi Pages 271-287
    The biosorption performance of Phlomis cancellata Bunge as inexpensive, abundant and easily available adsorbent for safranin cationic dye removal from aqueous system has been evaluated in a batch process, using response surface methodology and employing a central composite design Experimental. The influence of different parameters such as, pH, contact time, agitation rate and sorbent dosage on the removal of safranin was examined. The significance of independent variables and their interactions were tested by analysis of variance (ANOVA). The optimum contact time, pH, agitation speed and adsorbent dose were found to be 39.96 min, 9.0, 331.18 rpm and 20mg/mL, respectively. Under these conditions, the maximum sorption capacity for safranin was found to be 99.60%. The kinetics of dye sorption fitted well with pseudo-first order kinetic model. The isotherm data of safranin could be well described by Langmuir model (R2 = 0.9924). The method was successfully applied for the removal of safranin from industrial wastewater and groundwater samples.
    Keywords: Safranin, Removal, Aqueous System, Phlomis cancellata Bunge, Response Surface Methodology
  • Reyhaneh Jafariyan, Ali Mohammad Haji Shabani *, Shayessteh Dadfarnia, Elaheh Nourbala Tafti, Mahboube Shirani Pages 289-299
    A rapid, simple, and sensitive dispersive liquid-liquid microextraction based on solidification of floating organic drop (DLLME-SFOD) method coupled with UV–Vis spectrophotometry has been applied for the extraction and determination of trace amounts of aluminium. The aluminium was extracted from the aqueous media containing aluminon and cetyltrimethylammonium bromide (CTAB). After rapid injection of the mixture of 1-undecanol as the extraction solvent and ethanol as the disperser solvent into the sample, a cloudy mixture was formed and the complex was extracted into 1-undecanol. After centrifugation and cooling in an ice bath, the solidified organic drop on top of the solution was transferred into a vial which was melted at room temperature. Then, the organic phase containing the metal complex was diluted with ethanol and was transferred into a microcell for quantification. The pink chelate exhibits maximum absorbance at 535.0 nm, and with a preconcentration factor of 100.0 obeys Beer’s law over the concentration range of 1.0-15.0 µg L-1 of aluminium. The limit of detection of 0.14 μg L-1 and a relative standard deviation of 1.8% at 3.0 μg L-1 (n = 6) were obtained. The procedure was successfully applied for the determination of aluminium in tea and water samples.
    Keywords: Aluminium, Separation, preconcentration, DLLME-SFOD, Spectrophotometry
  • Fateme Rostamnejhad, Mohammad Hossein Fatemi *, Mahsa Samghani Pages 301-310
    The anti-oxidant activities for a diverse set of flavonoids as TEAC (Trolox equivalent anti-oxidant capacity), assay were subjected to 3D-QSAR (3 dimensional quantitative structural-activity relationship) studies using CoMFA (comparative molecular field analysis) and CoMSIA (comparative molecular similarity indices analysis). The obtained results indicated superiority of CoMSIA model over CoMFA model. The best CoMSIA model is developed by using hydrogen-bond donor (H-bond donor) and electrostatic field components. This model gave the cross-validated correlation coefficient, Q2 = 0.512, correlation coefficient, R2 = 0.950, standard error of prediction, SE = 0.284, and F = 47.3, for training set, R2 = 0.922 and SE = 0.286, for test set indicating robustness and high prediction power of the developed model. The contour maps of electrostatic and H-bond donor fields of CoMSIA model provide interpretable and fruitful relationship between chemicals structure and their anti-oxidant activities, which give useful insights for designing new compounds with higher activity.
    Keywords: 3D-QSAR, Anti-oxidant activity, CoMSIA, CoMFA, Flavonoids
  • P. Sumathi, Israel V. Muthu Vijayan Enoch * Pages 311-317
    Magnesium is an abundant element in the environment. Magnesium ion sensing by fluorescence spectral method is of importance due to the need for the detection of the metal in the human body and the environment. In this paper, we report the Mg2+ ion sensing behavior of the phenylhydrazone derivative of a difluorenylpiperidin-4-one. The preparation method of this compound is simple. The compound shows an enhanced absorption and fluorescence in the presence of Mg2+ ions, strikingly different from the other metal ions, which do not show significant spectral changes. The stoichiometry and the binding strength of the Mg2+ complex of the phenylhydrazone are determined. The compound shows an association constant of 3375.36 M-1 on binding to Mg2+. The range of detection and the competitive binding behavior of Mg2+ are reported. The phenylhydrazone of the difluorenylpiperidin-4-one shows appreciable selectivity and sensitivity of detection for Mg2+ ions. The compound shows promising result in determination of Mg2+ ions in water sample.
    Keywords: Mg2+ sensing, Piperidin-4-one, Phenylhydrazone, Fluorescent chemosensor, association
  • Atefeh Sharifat, Arash Larki *, Yadollah Nikpour Pages 319-328
    A simple and efficient dispersive liquid-liquid microextraction (DLLME) method coupled with microvolume UV-vis spectrophotometry was developed for the determination of trace amounts of phosphate. This method is based on the formation of phosphomolybdate due to the reaction between molybdate and phosphate followed by its reduction with stannous chloride in aqueous sulfuric acid medium. The blue product was converted into its ion-pair with methyltrioctylammonium chloride (Aliquat-336) and then extracted into an organic solvent (carbon tetrachloride) dispersed in aqueous solution. The factors influential to this procedure, such as concentration of sulfuric acid, ammonium molybdate and Tin(II) chloride in the sample solution, amount of methyltrioctylammonium chloride, volume of extraction solvent and reaction time were investigated and optimized. Under optimum conditions, the linear range was found to be 50-6500 ng mL-1 for phosphate, and the limit of detection to be 12 ng mL-1. The proposed method has been applied for the determination of trace amounts of phosphate in different water and wastewater samples and satisfactory results were obtained.
    Keywords: phosphate, Dispersive liquid-liquid microextraction, Aliquat-336, Methyltrioctylammonium chloride, Phosphomolybdate
  • Soleiman Bahar *, Elham Jomoor Pages 329-339
    A graphene oxide sorbent was modified with 8-hydroxyquinoline and used for solid phase extraction and selective determination of copper using flame atomic absorption spectrometry. In this method, a 5 mg of modified sorbent was added to 50 mL of aqueous solution containing 100 µgL-1 of Cu(II) at pH=3. The sorbent/aqueous solution mixture in the flask was stirred for 30 minutes and then centrifuged. Copper was desorbed from sorbent by 2 mL of 1 mol L-1 HCl, afterwards. The effect of several variables upon extraction efficiency, like: extraction time, pH adjustment and sorbent amount was studied. Under experimental conditions the enrichment factor of 25 was obtained by using of 50 mL of sample solution. The working dynamic range was from 5 to 800 ng mL-1. The limit of detection, limit of quantification and relative standard deviation were 2.16 ng mL-1, 6.51 ng mL-1, and 3 % for eight determinations of 100µg L-1 of Cu(II), respectively. The method was successfully applied for the determination of Cu(II) in black tea, rice and red pepper samples.
    Keywords: graphene oxide, Modification, 8-Hydroxylquinoline, copper, Food Samples
  • Mohammad Ali Sheikh, Mohseni * Pages 341-351
    An electrochemical sensor was fabricated by strontium ferrite (SrFe) nanostructure modified carbon paste electrode (SrFeME). This electrode showed good catalytic effect on oxidation of amino acid tyrosine (Tyr) in voltammetric studies. It can improve the anodic peak current of Tyr significantly and also decrease the oxidation overpotential of this amino acid. The peak current increased by two times and the overpotential is decreased more than 110 mV. The enhancing of oxidation signal of Tyr at modified electrode is related to the improving the electron transfer rate at these nanoparticles and increasing the active surface area of the modified electrode by the nanoparticles. This electrode was used as an electrochemical sensor for the measurement of Tyr by differential pulse voltammetry. The anodic peak current was linearly related to Tyr concentration in the range from 0.8 μM to 300.0 μM and the detection limit was calculated as 0.15 μM (S/N = 3). The presence of ascorbic acid, dopamine, glucose and a number of ions could not affect the Tyr measurement. Finally, the proposed sensor was successfully used for measurement of Tyr in real samples.
    Keywords: Electrode, Electroanalysis, Nanomaterials, Voltammetry
  • Mohammad Hassannejad, Kamal Alizadeh *, Mahboob Nemati Pages 353-363
    The aim of the present study was to extract, preconcentrate and determine 17-β–Estradiol in water samples using a simple and efficient method; to this aim, salting-out-assisted liquid-liquid extraction and high-performance liquid chromatography with ultra violet detection at 210 nm were performed. Water-miscible acetonitrile, as the extractant and acetonitrile phase separation under high-salt conditions were applied to treat the samples. The extraction efficiency and method sensitivity were carefully monitored by controlling the effective factors and the optimum conditions were: Sodium chloride as the salting-out agent at concentration of 1.6 g, 2.40 mL of acetonitrile as extraction solvent, 5 mL of water sample, vortexing for 2 minutes and centrifuging at 4000 rpm for 5 minutes. A central composite design was applied to optimize the hydrolysis parameters. Using optimized experimental conditions, the calibration curve was found to be linear in the range of 1–120 µg L-1 in water sample and the correlation coefficient (R2); the limit of detection; limit of quantification were >0.99, 0.25 µg mL-1 and 0.83 μgL-1, respectively. The enrichment factor and extraction recoveries of the selected analyte ranged from 44.96 to 49.57 and 89.93 to 99.15% respectively. Relative standard deviations are about 5.94%. High extraction efficiency and compatibility with HPLC analysis of 17-β–Estradiol in water samples are the advantages of this method.
    Keywords: Salting-out-assisted, liquid-liquid extraction, 17-?-Estradiol, Central composite design
  • Saeed Mohammad Sorouraddin *, Mir Ali Farajzadeh, Hossein Najafpour Qarajeh Pages 365-380
    A green effervescence-assisted dispersive liquid-liquid microextraction based on phthalic acid as a complexing agent and co-disperser coupled with graphite furnace atomic absorption spectrometry has been developed for the extraction and preconcentration of Co(II) and Ni(II) from aqueous samples. Initially two test tubes were selected. A specified amount of sodium bicarbonate is placed at the bottom of the first conical and dried glass test tube, and then µL-level of 1,1,2,2-tetrachloroethane as an extraction solvent is added. Phthalic acid (as a complexing agent) is added to the aqueous solution placed in the second tube to form phthalate-metal complexes. Then, the content of the second tube is added into the first tube. A reaction between the excess amount of phthalic acid and sodium bicarbonate is immediately occurred, and the produced CO2 leads to dispersion of the extraction solvent as tiny droplets. In this study, phthalic acid is used simultaneously as complexing agent and co-disperser. Under the optimum conditions the calibration curves were linear in the ranges of 25.0-1000.0 and 50.0-1000.0 ng L-1 for Co(II) and Ni(II), respectively. The detection limits were obtained 9.2 and 15.0 ng L-1 for Co(II) and Ni(II), respectively. Extraction recoveries were 99 and 98% for Co(II) and Ni(II), respectively. Enrichment factors were obtained 197.8 and 196.4 for Co(II) and Ni(II), respectively. The relative standard deviations were ≤1.3% for intra- (n = 6) and ≤3.0 for inter-day (n=6) precisions. Finally, the proposed method was successfully applied for the simultaneous analysis of the analytes in environmental water and fruit juice samples.
    Keywords: Cobalt, nickel, Phthalic acid, Effervescence-assisted dispersive liquid-liquid microextraction, Graphite furnace atomic absorption spectrometry
  • N Sudha, Y. Israel V.M.V. Enoch *, Y Sameena Pages 381-391
    The objective of the paper is to determine the effect of β-cyclodextrin complexation on the interaction of the popular drug, Atorvastatin to bovine serum albumin. Fluorescence and 2D Rotating-frame Overhauser effect spectroscopic techniques are used to determine the stoichiometry, the binding contant, and the mode of binding of Atorvastatin to β-cyclodextrin. The role of the Atorvastatin–β-cyclodextrin complexation in modulating the binding strength of the drug to the model carrier protein bovine serum albumin is studied using absorption and fluorescence spectral measurements and molecular docking. Atorvastatin shows a fluorescence enhancement on comlplex formation with β-cyclodextrin. The results of the binding of the drug to bovine serum albumin in free– and β-cyclodextrin–bound forms. The magnitude of quenching of the fluorescence of bovine serum albumin due to drug binding, an d the Fӧrster energy transfer efficiency between the protein and the drug are decreased in the presence of β-cyclodextrin. The binding constant value of the drug–protein binding in the absence and presence of β-cyclodextrin are 5.36 × 104 M-1 to 2.32 × 104 M-1 respectively. Atorvastatin forms a 1:2 inclusion complex with cyclodextrin. The isopropyl substituent in the pyrrole ring of Atorvastatin binds to β-cyclodextrin. Cyclodextrin modulated the binding of drug to the serum albumin, i.e., the cyclodextrin complex of Atorvastatin binds to bovine serum albumin with diminished binding strength. Nevertheless, the exposed part of the drug is found to be sufficient for interaction with the same binding pocket as the free drug binds to.
    Keywords: ?-Cyclodextrin, Atorvastatin, Fluorescence, FRET, Bovine serum albumin, 2D ROESY
  • Zahra Hassanvand, Fahimmeh Jalali * Pages 393-404
    Electrochemical deposition of gold nanoparticles (AuNPs) and l-Cysteine on glassy carbon electrode was carried out to prepare a modified electrode. The fabricated sensor showed good sensitivity and selectivity for simultaneous determination of paracetamol (PAR) and tramadol (TRA) by square wave voltammetry. Linear ranges of 0.10 - 10.7 μM (PAR) and 0.50 - 63.6 μM (TRA) were obtained with detection limits of 0.03 and 0.17 μM, respectively. The relative standard deviation (RSD %) for simultaneous determinations of PAR (10 µM) and TRA (30 µM) was calculated to be 3.11 and 3.30%, respectively (5 replicate determinations). Moreover, when 3 different electrodes were used, RSD% for PAR and TRA was 3.92 and 4.02%, respectively. The proposed electrode was used successfully in the simultaneous determination of the drugs in spiked human plasma samples.The calculated recoveries for PAR and TRA in blood serum were found to be in the rage 99.5-102 %, with RSD% 0.71 – 1.9%.
    Keywords: Paracetamol, Tramadol, Modified electrode, Cysteic acid, Gold Nanoparticles, Square wave
  • Vida Izadkhah *, Mosayeb Rezaei, Jafar Mahmoodi Pages 405-417
    In the present paper, the use of a modified electrochemical sensor for the determination of Pb2+ is described. The sensor is based on a carbon paste electrode modified with Nitro benzoil diphenyl methylene phosphorane, N-octylpyridiumhexafluorophosphate (OPPF6) and Fe3O4 nanoparticles. In this work, the oxidation of lead at the modified electrodes were investigated by square wave voltammetry (SWV). The structure of the nanoparticle was investigated by X-ray Powder Diffraction (XRD), Scanning electron microscopy (SEM) and Energy dispersive X-ray spectrum. The effective parameters on response of the electrode such as effect of the electrode composition, pH of solution, deposition potential and accumulation time and also instrumental SWV method were studied. In optimum conditions, the Anodic stripping voltammetry (ASV) was used for the determination of Pb2+. It is found that the calibration graphs of Pb2+ are linear in the concentration ranges from 1.20–120 nM. The detection limit of the method was 0.9 nM. The sensor was applied to validate its capability for the analysis of Pb2+ in the water and fish samples.
    Keywords: Voltammetric determination, Lead ion, Modified electrode, anodic stripping voltammetry, Fe3O4 nanoparticle, Ionic Liquid
  • Fahimeh Rasolzadeh, Payman Hashemi *, Maryam Madadkar Haghjou, Mehdi Safdarian Pages 419-429
    A sensitive, relatively selective and semi-automated microextraction by packed sorbent (MEPS) method was developed for the spectrophotometric determination of nitrofurantoin (NFT) in urine samples using a green sorbent. Chlorella vulgaris, a unicellular green microalgae, was used for the first time, as a biosorbent in the developed MEPS method. Effects of several factors such as sample volume, eluent volume, sample pH and no. of extraction cycles (draw-ejects) on the performance of the method were carefully studied. It was found that NFT is quantitatively enriched on the packed syringe from a sample adjusted on pH 8, after 14 draw-eject cycles. This procedure was easily performed by a designed reciprocating apparatus. After washing the sorbent for removing matrix interferences, the analyte was eluted by 30% acetone in water as eluent. Under the optimized conditions, a detection limit of 0.039 mg L-1 and a linear calibration curve with an R2 of 0.997 was obtained for NFT determination. The precision of the method expressed as relative standard deviation was 3.54 for six replicates. The method was successfully applied to the determination of NFT in human urine samples.
    Keywords: Nitrofurantoin, Microalgae chlorella vulgaris, Microextraction by packed sorbent, Biosorption
  • Chimaobi Ononamadu *, Godwin Ihegboro, Tajudeen Owolarafe, Kailani Salawu, Muhjib Fadilu, Obiajulu Ezeigwe, Moses Oshobu, Francis Nwachukwu Pages 431-439
    Ocimum canum belongs to a genus of aromatic annual and perennial herbs and shrubs in the family of Lamiaceae. It is native to Africa and cultivated commonly for its culinary and medicinal value. In a previous study, we reported the antioxidant and hypoglycemic activity of the crude methanol extract and the solvent fractions of Ocimum canum leaves.This present study was aimed to partially isolate and identify some bioactive compounds in the aqueous-methanol solvent fraction of methanol extract of Ocimum canum leaves. The sample was fractionated via silica gel-column and solvent system to yield many fractions which was pooled using analytical TLC. The pooled fractions were screened for antioxidant activity (DPPH scavenging assay and Ferric Reducing Power) and ability to reduce fasting blood glucose (FBG). The most active sub fraction was analysed with LC-MS and GC-MS to identify the active compounds. A total of 197 fractions were collected and pooled to seven (7) subfractions. Subfraction OC4 showed the best activity with IC50s 48.6±6.6µg/ml and 15.2±3.9µg/ml for DPPH scavenging and Ferric Reducing Power assays respectively, a 37% reduction in FBG and a concomitant increase in insulin level in treated diabetic rats. The LC/GC-MS analysis revealed tentatively the following compounds: Diosmetin, Dihydroquercetin, Digalloyl glucose isomer, Ananaflavoside isomer, Kaempferol glucoside embinin isomers, eugenol, hexadecanoic acid, 9,12 octadecanoic acid, and β-sitosterol. The study corroborates the previously reported antioxidant activity and hypoglycemic potential of the leaves of Ocimum canum and further more identified bioactive compounds that can be isolated and further characterised.
    Keywords: Ocimum canum, Hypoglycemic, Antioxidant, LCMS, GCMS
  • Morteza Bahram *, Negar Mohammadzadeh Pages 441-448
    So far, much research has been conducted to measure drug analytes both in pure form or simultaneously and different methodologies have been employed with their respective advantages and disadvantages. In this work, we have tried to carry out efficient measurements with lower cost and shorter time using MCR-ALS for simultaneous determination of Furosemide and Rizatriptan benzoate in their mixtures by analyzing kinetic-spectrophotometric data matrices obtained from monitoring of the drug degradation reactions induced by chlorine at optimized pH. Because of the presence of high spectral overlapping between the analyzed drugs and similar kinetic profiles, the obtained matrix is rank-deficient and hence matrix augmentation was performed for simultaneous analysis of drugs in their mixture. Calibration curves were linear in the ranges 3- 50 μM and 2- 50 μM for Furosemide and Rizatriptan respectively. Satisfactory recoveries were obtained and the method showed good analytical performance toward determination of Furosemide and Rizatriptan in real samples.
    Keywords: Furosemide, Rizatriptan, MCR-ALS, Simultaneous, Kinetic-spectrophotometric, degradation
  • Karamali Ghalkhani *, Mohammad Javad Chaichia, Mahdi Hashemi, Mohammad Fatemi Pages 449-456
    The effects of environmental parameters, including solvent, pH and ionic strength on the fluorescence features of aflatoxin B1, B2, G1 and G2 were investigated. Fluorescence spectral characteristics such as fluorescence emission intensity, stokes shift and maximum emission wavelength were markedly affected by solvent type. The emission fluorescence peak of aflatoxins has been assessed between 370 and 500 nm under a 360 nm excitation source. The maximum fluorescence intensities were obtained with ethanol and acetonitrile for all aflatoxins studied. The maximum displacement on emission wavelengths for aflatoxin B1, B2, G1 and G2 were obtained in methanol, dichloromethane, chloroform and acetonitrile, respectively. The study of the acidity showed that maximum signal intensity was obtained in relatively low acidity values. Also the study of ionic strength revolved that the maximum signals were obtained in 0.1 M NaCl. Also, this study shows that there is no need for another fluorophore for the study of investigated aflatoxins.
    Keywords: Aflatoxin, Spectrofluorimetric, Solvent effect, Ionic strength, Mycotoxin, Carcinogen, Stokes shift
  • Rajamohan Rajaram *, Kothai Nayaki S, Swaminathan M, Sivakumar K Pages 457-476
    The spectral characteristics of 2-aminobenzimidazole (2ABZ) in aqueous and β-cyclodextrin media has been investigated using absorption, steady state and time resolved fluorescence techniques. The stoichiometric ratio of the inclusion complex of neutral and monocationic forms of 2ABZ in β-CDx medium is found to be 1:1. There is no significant differences between ground and the excited state pKa values of 2ABZ under both the media and thus the amino group of 2ABZ molecule is not much affected by the complexation process i.e., it lies outside the β-CDx cavity. Considering the shape and dimensions of β-CDx, it is clear that the 2ABZ molecule cannot be completely included in the β-CDx cavity. Because, the overall height of 2ABZ is 10.6 Å, but the overall height of β-CDx is only 7.8 Å. Hence, it is possible to locate half of the 2ABZ molecule only permitted inside the β-CDx cavity as interpreted using experimental data.
    Keywords: 2-Aminobenzimidazole, inclusion complex, Lifetime, Acidity constant, Patch-Dock server