Iranian Chemical SocietyAnalytical and Bioanalytical Chemistry Research2383-093X1120140601A Review on Application of Microextraction Techniques for Analysis of Chemical Compounds and Metal Ions in Foodstuffs119480710.22036/abcr.2014.4807ENMir Ali FarajzadehUniversity of TabrizLeila KhoshmarramUniversity of TabrizSaheleh SheykhizadehUniversity of TabrizJournal Article20130807Foodstuffs analysis is very important due to population growth and increasing consumer demand for safety and nutritional excellence. The Analysis of different compounds in foodstuffs is so difficult without using sample preparation techniques. Traditional techniques require large amounts of toxic organic solvents. As a result, they are not only expensive but also environmentally unfriendly and they generate a considerable amount of waste. Nowadays efforts are being focused on development of microextraction techniques. Different microextraction techniques such as solid phase microextraction (SPME), stir bar sorptive extraction (SBSE), and liquid phase microextraction (LPME) have found an important place in sample preparation because of their inherent advantages over the conventional procedures. In particular, they have been applied with successfully for the analysis of food samples despite their complexity. The review discusses different microextraction approaches used in analysis of chemical compounds and metal ions in foodstuffs. It summarizes the application of microextraction techniques in food analysis in details as possible.https://www.analchemres.org/article_4807_8009df5212e107cb130d313cea2aa968.pdfIranian Chemical SocietyAnalytical and Bioanalytical Chemistry Research2383-093X1120140601Preconcentration and Speciation of Chromium Using Dispersive Liquid-Liquid Microextraction; Application to Milk and Different Water Samples2028478410.22036/abcr.2014.4784ENM. AdibmehrDepartment of Chemistry, Islamic Azad University, Tehran Central Branch, Tehran , IranH. Bagheri SadeghiDepartment of Chemistry, Islamic Azad University, Tehran Central Branch, Tehran , IranSh. Dehghan AbkenarDepartment of Chemistry, Islamic Azad University, Savadkooh Branch, Mazandran, IranJournal Article20130529A simple and rapid microextraction procedure based on dispersive liquid-liquid microextraction (DLLME) was developed for determination and speciation of trace amounts of chromium (Cr) by flame atomic absorption spectrometry (FAAS). In the proposed approach, chloroform and methanol were used as extraction and dispersive solvents. A new Schiff's base ligand, bis(2-methoxy benzaldehyde) ethylene diimine was used as complexing agent. Effect of extraction solvent, disperser solvent, the volume of extraction and disperser solvent, pH of the aqueous solution and extraction time on extraction procedure were investigated and optimized. Under the optimum conditions, the calibration graph was linear in the range of 1-50 µg l<sup>-1</sup> with a limit of detection of 0.7 µg l<sup>-1</sup>. The relative standard deviation (RSD%) was 2.7% (n = 7) for Cr(III). The relative recoveries of spiked samples were between 98% and 102% and preconcentration factor (PF) was 20. The proposed method is a simple, fast, accurate, highly stable and selective and was applied for determination of chromium in milk and water samples with satisfactory results.https://www.analchemres.org/article_4784_d5ee4248f11284fb903ab88376eb50f0.pdfIranian Chemical SocietyAnalytical and Bioanalytical Chemistry Research2383-093X1120140601Central Composite Design for the Optimization of Hydrogel Based pH-Dependent Extraction and Spectrophotometric Determination of Mercury2937550310.22036/abcr.2014.5503ENMorteza BahramDepartment of Chemistry, faculty of Science, Urmia University, Urmia, IranShima JahangiriDepartment of Chemistry, Faculty of Science, Urmia University, Urmia, IranKhalil FarhadiDepartment of Chemistry, Faculty of Science, Urmia University, Urmia, Iran0000-0002-0487-6099Reza HasanzadehDepartment of Chemistry, Faculty of Science, Urmia University, Urmia, IranJournal Article20130722In the present work a pH-dependent cloud point extraction procedure using pH-sensitive hydrogel polymer was applied for preconcentration and spectrophotometric determination of the Hg(II) as its Thio micher's ketone complex. Central composite design (CCD) and response surface method were applied to design the experiments and find out the optimum conditions. Four factors entitled concentration of hydrogel, HCl, TMK and KCl (to study the salting out effect) were investigated. At the optimum conditions, the analytical characteristics of the method (<em>e.g.</em>, limit of detection, linear range, Relative standard deviation) were obtained. Linearity was obeyed in the range of 5-200 ng ml<sup>-</sup><sup>1</sup> of Hg(II) with a correlation coefficient of 0.987. The detection limit of the method was 1 ng ml<sup>-</sup><sup>1</sup> for Hg(II) ion. Relative standard deviation (RSD) for 7 replicate determinations of complex mercury with Thio micher's ketone was 3.37%. The interference effect of some anions and cations was also investigated. https://www.analchemres.org/article_5503_da417648627cf99bc95797ba6861e630.pdfIranian Chemical SocietyAnalytical and Bioanalytical Chemistry Research2383-093X1120140601Simultaneous Determination of Disinfection By-products in Water Samples from Advanced Membrane Treatments by Headspace Solid Phase Microextraction and Gas Chromatography-Mass Spectrometry3849559510.22036/abcr.2014.5595ENEva PocurullUniversitat Rovira i VirgiliCarolina MartínezUniversitat Rovira i VirgiliVerónica GómezDow Water & Process Solutions, Dow Chemical Ibérica S.L.Francesc BorrullUniversitat Rovira i VirgiliJournal Article20140218A headspace-solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) method has been developed for the simultaneously determination of 20 disinfection by-products (DBPs) in water samples from reverse osmosis (RO) membranes. Selected compounds belong to different families including: trihalomethanes (THMs), halogenated acetonitriles (HANs), halogenated nitromethanes (HNMs), halogenated ketones (HKs) and other halogenated DBPs. Four commercial fibres with different polarities were tested for the extraction of the compounds and the main variables affecting HS-SPME such as extraction time, extraction temperature and pH of the samples were optimized by applying a central composite design. The method showed good detection limits in the range of 0.003 mg l<sup>-1</sup> up to 0.010 mg l<sup>-1</sup> for most of the compounds with reasonable linearity with r<sup>2</sup> higher than 0.991. Moreover, the repeatability of the method, expressed as relative standard deviation (RSD) was lower than 13% (n = 5, 1 mg l<sup>-1</sup>) in brackish and wastewater samples. The validated method has been applied for the determination of the target DBPs in RO water samples from application research units, which treated water from various origins (wastewater, brackish water and sea water), showing good performance in the different types of studied samples. The analysis revealed the presence of several DBPs regarding different families, such as trichloromethane (with concentrations up to 0.36 μg l<sup>-1</sup>), chloroiodomethane (0.5-1.44 μg l<sup>-1</sup>), dibromochloromethane (found at concentrations up to 0.76 μg l<sup>-1</sup>) and tribromoacetaldehyde (at concentrations up to 11 μg l<sup>-1</sup> in the influent samples). The tendency of most of them indicated a trend of removal by reverse osmosis treatments, especially the total concentration of THMs which decreased below the limit of detection.https://www.analchemres.org/article_5595_5f7d05aa82cb9c089d86267ae11c7d92.pdfIranian Chemical SocietyAnalytical and Bioanalytical Chemistry Research2383-093X1120140601Chemical Modification of Activated Carbon and Its Application for Solid Phase Extraction of Copper(II) and Iron(III) Ions5061596810.22036/abcr.2014.5968ENM. Ghaedichemistry department, yasouj universityM. MontazerozohoriChemistry Department, Yasouj University, Yasouj Iran 75914-353H. SaidiGachsaran Azad University, Gachsaran Branch, Gachsaran, IranM. RajabiDepartment of Chemistry, Semnan University, Semnan 35195-363, IranJournal Article20130710Powder activated carbon surface (AC) was grinded and modified and altered procedure thorough a facile and easy chemical reaction to appearance of 2-((3silylpropylimino)1-methyl) phenol (AC- (SPIMP)). Subsequently, this novel sorbent efficiently applied for the extraction and preconcentration of some metal ions from real samples. Preliminary the influences of variables such as pH, amounts of reagents and porous AC, eluting solution conditions (type and concentrations), sample volume and influence of interference of many ions on the analytes recoveries was studied and optimized. This new sorbents property including pore size, pore volume and surface properties was evaluated and monitored by BET, while structure and homogeneously of sorbent was identified by SEM. The surface modification was traced by FT-IR as powerful and strong identification techniques. The proposed sorbent has high surface area(>1317.1346 m2 g-1) and small pore size(https://www.analchemres.org/article_5968_f98ca975478bcac9869e18e49aa1d42e.pdfIranian Chemical SocietyAnalytical and Bioanalytical Chemistry Research2383-093X1120140601Simultaneous Voltammetric Measurement of Ascorbic Acid, Epinephrine, Uric Acid and Tyrosine at a Glassy Carbon Electrode Modified with Nanozeolite-Multiwall Carbon Nanotube6272596610.22036/abcr.2014.5966ENMeissam NoroozifarUniversity of Sistan and BaluchestanMozhgan Khorasani Motlaghuniversity of Sistan and BaluchestanReza AkbariUniversity of Sistan and BaluchestanMojtaba Bemanadi PariziUniversity of Sistan and BaluchestanJournal Article20131006In this study, incorporation of iron ion-doped natrolite nanozeolite, multi-wall carbon nanotubes into chitosan-coated glassy carbon electrode for the simultaneous determination of ascorbic acid, epinephrine, uric acid and tyrosine is studied. The results show that the combination of multi-wall carbon nanotubes and iron ion-doped natrolite zeolite causes a dramatic enhancement in the sensitivity of ascorbic acid, epinephrine, uric acid and tyrosine quantification. The sensor gave the separated and sharp voltammetric responses of analytes in four well-defined linear sweep voltammetry peaks. Under the optimum conditions, the calibration curve were linear up to 1.82 × 10<sup>-3</sup>, 3.15 × 10<sup>-3 </sup>, 1.50 × 10<sup>-4</sup> and 6.29 × 10<sup>-4</sup> M with detection limits 1.82 × 10<sup>-6</sup>, 1.33× 10<sup>-6</sup>, 4.09 × 10<sup>-8</sup> and 2.01× 10<sup>-7 </sup>M (S/N<em>=</em> 3) for ascorbic acid, epinephrine, uric acid and tyrosine, respectively. The analytical performance of this sensor has been evaluated for simultaneous detection of four analytes in human serum and urine samples.https://www.analchemres.org/article_5966_6cbb8ef0faa578fda16b36dae4714457.pdfIranian Chemical SocietyAnalytical and Bioanalytical Chemistry Research2383-093X1120140601Al(III) Coated Wire Selective Electrode Based on 5-Bromo(salicylidene-2-aminothiophenol) Schiff Base as a New Ionophore7382596710.22036/abcr.2014.5967ENA. ShokrollahiDepartment of Chemistry, Yasouj University 75918-74831, Yasouj, Iran0000-0002-3841-0852A. AbbaspourbDepartment of Chemistry, Shiraz University, Shiraz, IranA. Naghashian HaghighiaDepartment of Chemistry, Yasouj University, Yasouj, IranA. H. KianfarDepartment of Chemistry, Isfahan University of Technology, Isfahan, IranJournal Article20130930A new Al(III) selective membrane based on 5-bromo(salicylidene-2-amino thiophenol) as a neutral carrier in a poly(vinyl chloride) (PVC) matrix is coated on platinum wire to determine trace amounts of Al(III) ion in various samples. The sensor exhibits a good response for Al(III) ion over a wide concentration range of 5.20 × 10<sup>-7</sup> to 1.00 × 10<sup>-2</sup> M with Nernstian slope of 19.64 ± 0.15 mV decade<sup>-1</sup> and low detection limit of 5.01 × 10<sup>-7</sup> M. The performance of the sensor is best in the pH range of 4.00-6.50 without any divergence in potential and it also works well in partially non-aqueous medium. The coated wire electrode has a short response time of about 5 s and is stable for at least 2 months. The proposed membrane electrode revealed good selectivity for Al(III) ion over a wide variety of other metal ions. It was successfully applied for determination of Al(III) ion in different real and environmental samples and also as an indicator electrode for potentiometric titration of Al(III) ion with EDTA.https://www.analchemres.org/article_5967_5b7023968991ca1c4ecb0e276acecb61.pdf