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Analytical and Bioanalytical Chemistry Research - Volume:4 Issue: 1, Winter - Spring 2017

Analytical and Bioanalytical Chemistry Research
Volume:4 Issue: 1, Winter - Spring 2017

  • تاریخ انتشار: 1395/11/17
  • تعداد عناوین: 14
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  • Abbas Afkhami, Massoumeh Pirdadeh, Beiranvand, Tayyebeh Madrakian Pages 1-10
    A method based on the ultrasound-assisted solidification of floating drop microextraction technique was developed for the spectrophotometric and spectrofluorimetric determination of curcumin in turmeric powder. In this work a small volume of an organic solvent was floated on the surface of an aqueous solution. After sonication the organic solvent is solidified and separated. The effect of extraction parameters such as type and the volume of organic solvent, temperature, salt addition and exposure time, on the extraction recovery was investigated and optimized. Finally, the method droplet was used for the determination of analyte. Under the optimum extraction conditions, a linear range of 0.006–30 μg mL-1 and a relative standard deviation (RSD) of 2.72% for curcumin wasachieved. Limits of detection of 7 and 2 ng mL-1 curcumin was obtained for the spectrophotometric and spectrofluometric methods, respectively. The obtained results show that the application of this method can be successful for the analysis of curcumin in turmeric powder samples.
    Keywords: Curcumin, Solidification of floating drop microextraction, Spectrophotometriy, Spectrofluorimetry, Turmeric powder
  • Mohsen Keyvanfard, Behzad Rezaei, Khadijeh Alizad Pages 11-20
    Nowadays, palladium compounds due to their especial characteristics used in different industries, mainly in electrical power sources and chemical productions as a catalyst. Therefore, Pd concentration is increasing in our around that can be contaminant our environment due its toxic effects. In this work, a simple, selective and rapid flow injection method of analysis (FIA) has been developed for ultra-trace determination of palladium. The method is based on catalytic effect of palladium on the oxidation of naphthol green B by periodate. Naphthol green B undergoes an oxidation reaction with metaperiodate in acidic medium to from a colorless product at very slow rate. It was found that this reaction can be sharply done at the present of trace amount of Pd(II). The reaction was monitored spectrophotometrically by measuring the difference between absorbance of naphthol green B of solutions with and without Pd(II), at the λmax= 721 nm. The reagents and manifold variables, which have influences on the sensitivity, were investigated and the optimum conditions were established. At these conditions, the influences of some important species on the determination of palladium by flow system were examined and most of them do not have any interference effect on its flow injection determination. It is obvious that under the optimized conditions absorbance signal was linearly depended on palladium concentrations in the ranges of 2.0–90.0 ng/mL with a detection limit of 0.9 ng/mL (S/N= 3) and a sample rate of 35±5 samples/h.
    Keywords: Palladium(II), Flow injection analysis, Spectrophotometry, Naphthol green B
  • Faezeh Khalilian, Mohammad Farajvand Pages 21-29
    A solid phase extraction sorbent based on polyaniline/graphene nanocomposite is presented. The structure and morphology of synthesized nanocomposite were investigated by Fourier transform infrared spectroscopy, field emission scanning electron microscopy, X-ray diffraction and thermal gravimetric analysis. The dispersive solid phase extraction was employed to the isolation and preconcentration of avermectins insecticide (mixture of B1a and B1b). The extraction procedure was investigated by high performance liquid chromatography-UV detection. The sorbent demonstrated a favorable analytical performance for avermectins detection with reasonable linear ranges (1.5-1000 μg L-1 and 5.0-1000 μg L-1 for B1a and B1b in order) and acceptable detection limits (0.5 μg L-1 for B1a and 2.5 μg L-1 for B1b) under optimized conditions. The extraction efficiency of polyaniline/graphene nanocomposite in the extraction of avermectins was compared with graphene, polyaniline, carbon nanotube and C18 sorbents. Moreover, the applicability of proposed method was assessed for the extraction of analyte from citrus fruit juice.
    Keywords: Polyanilline, graphene nanocomposite, Dispersive solid phase extraction, Avermectins, High performance liquid chromatography, Citrus fruit juice
  • Karim Asadpour Zeynali, Venus Baghalabadi Pages 31-40
    In this work poly eriochrome black T (EBT) was electrochemically synthesized on the glassy carbon electrode as electrode modifier. On the modified electrode, voltammetric behavior of isoniazid (INH) was investigated. The poly (EBT)-modified glassy carbon electrode has excellent electrocatalytic ability for the electrooxidation of isoniazid. This fact was appeared as a reduced overpotential of INH oxidation in a wide operational pH range from 2 to 13. It has been found that the catalytic peak current depends on the concentration of INH and solution pH. The number of electrons involved in the rate determining step was found 1. The diffusion coefficient of isoniazid was also estimated using chronoamperometry technique. The experimental results showed that the mediated oxidation peak current of isoniazid is linearly dependent on the concentration of isoniazid in the ranges of 8.0 × 10-6 – 1.18 × 10-3 M and 2.90 × 10-5 M – 1.67× 10-3 M with differential pulse voltammetry (DPV) and amperometry methods, respectively. The detection limits (S/N = 3) were found to be 6.0 μM and 16.4 μM by DPV and amperometry methods, respectively. This developed method was applied to the determination of isoniazid in tablet samples with satisfactory results.
    Keywords: Isoniazid, Poly (eriochrome black T) modified electrode, Voltammetric behavior, Determination
  • Kanakapura Basavaiah, N. Rajendraprasad Pages 41-51
    Metformin hydrochloride (MFH) is an oral anti-diabetic drug of biguanide class. Two selective spectrophotometric methods were presented for the determination of MFH in pharmaceuticals. The methods were based on the measurement of yellow-coloured charge-transfer complexes formed between MFH and two poly-nitrophenols, namely, 2,4-dinitrophenol (DNP method, at 405 nm) and picric acid (PA method; at 410 nm) in dichloromethane medium. The variables which affect the complex formation were studied and optimized. Beer’s law was obeyed over the concentration ranges: 2.4-48.0 and 3.2-64.0 µg ml-1 with molar absorptivity values of 3.24 × 103 and 2.30 × 103 l mol-1 cm-1, with DNP method and PA method, respectively. The limits of detection (LOD) and quantification (LOQ) were calculated to be 0.13 and 0.40 µg ml-1 for DNP method and 0.19 and 0.59 µg ml-1 for PA method. Methods were validated for accuracy, precision, robustness, ruggedness and selectivity. The proposed methods were applied to the determination of MFH in tablets. The accuracy and precision of the methods were found excellent. Accuracy of the methods was ascertained by recovery test via standard-addition procedure. The methods were applied to spiked human urine sample without detectable interference from endogenous substances.
    Keywords: Metformin hydrochloride, Nitrophenols, Spectrophotometry, Charge, transfer complex, Pharmaceuticals, Spiked human urine
  • Morteza Bahram, Saed Salami, Mehdi Moghtader, Peyman Najafi Moghadam, Amir Reza Fareghi, Masoumeh Rasoli, Samaneh Salimpoor Pages 53-63
    The photocatalytic degradation of two anionic azo dyes Acid Red88 (AR 88) and Acid Orange 7 (AO7) was investigated in aqueous solution using a TiO2-containing hydrogel and UV light. The pH-sensitive hydrogel poly (styrene-alt-maleic anhydride) (PSMA), was synthesized and crosslinked in the presence of melamine and TiO2 nanoparticles which results in entrapment of TiO­2 into the melamine-grafted PSMA (M-g-PSMA) hydrogel. Potential application of this nanocomposite for removal of azo dyes from wastewater was studied and the effective parameters on degradation process including time, initial pH value of the solutions, temperature and amount of added nanocomposite were optimized. The optimized values for effective parameters are as follows: time: 30 min, initial pH of the solutions: 5.23 for AO7 and 5.3 for AR88, temperature: 24 ºC and amount of added nanocomposite: 250 mg. Results showed that in optimum experimental conditions the removal percentages are about %94 for AR88 and %71 for AO7 indicating good removal performance toward the method whilst pH-sensitivity of the nanocomposite facilitates retrieval of nanocatalyst at the end of the reaction.
    Keywords: Photocatalytic degradation, Hydrogel, TiO2, azo dye, Acid Red 88, Acid Orange 7
  • Ghodratollah Absalan, Asma Bananejad, Maryam Ghaemi Pages 65-77
    The applicability of Fe3O4 nanoparticles (Fe3O4NPs) for removing alizarin and purpurin from aqueous solutions has been reported. The influence of nanoparticle dosage, pH of the sample solution, individual dye concentration, contact time between the sample and the adsorbent, temperature, and ionic strength of the sample solution were studied by performing a batch adsorption technique. The maximum removal of 5-100 mg l-1 of individual dyes from an aqueous sample solution at pH 5.0 was achieved within 5.0 min when an adsorbent amount of 20 mg was used. The kinetic results revealed that the pseudo-second-order equation is the best model to analyze the adsorption mechanism. The isotherm analysis indicated that the equilibrium data are well fitted to the Langmuir isotherm model with maximum adsorption capacities of 45.87 and 40.48 mg g-1 of the adsorbent for removal of alizarin and purpurin, respectively. According to the experimental results, about 99% of alizarin and 95% of purpurin were removed from aqueous solutions under applying the optimal experimental conditions.
    Keywords: Iron oxide magnetic nanoparticles, Alizarin red, Purpurin, Dye removal, Anthraquinone dyes
  • Akram Valipour, Mahmoud Roushani Pages 79-90
    A highly sensitive electrochemical immunosensor was developed to detect hCG based on immobilization of hCG-antibody (anti-hCG) onto robust nanocomposite containing Gr, Chit, 1-methyl-3-octyl imidazolium tetra fluoro borate ionic liquid (IL) (Gr-IL-Chit). AuNPs were used to immobilize hCG antibody on the modified electrode. The amine groups of the antibody are covalently attached to AuNPs/Gr-IL-Chit nanocomposite. CV, EIS and SEM were employed to characterize the assembly process and the performance of the immunosensor. DPV and EIS studies demonstrated that the formation of antibody-antigen complexes decreased peak current and increased Rct of [Fe(CN)6]3−/4− redox pair at the AuNPs/Gr-IL-Chit/GCE. The optimization of the pH of supporting electrolyte and the incubation time were studied in details. Because of the synergistic effect of IL, Chit and Gr and the unique properties of AuNPs, the obtained immunosensor exhibited a wide linear response to hCG in two ranges from 0.005-1.484 and 1.484-411.28 (mIU ml-1). A relatively low detection limit of 0.0016 mIU ml-1 (S/N = 3) was calculated from DPV. Satisfactory results were obtained for determination of hCG in human serum samples.
    Keywords: Electrochemical immunosensor, Human chorionic gonadotropin, Nanocomposite, Impedance spectroscopy
  • Abdolhossein Naseri, Bahar Ghasemzadeh, Saheleh Sheykhizadeh Pages 91-103
    A new method was developed for the spectral resolution by further determination of three- and four-component mixtures of drugs in urine samples through the complementary application of multivariate curve resolution-alternating least squares with correlation constraint. In the current study, a simple method was proposed to construct a calibration set for the mixture of drugs in the presence of all possible interferents in the human urine samples collected, in duplicate, from volunteers. First, urine samples were collected without any dosage of drugs. Then, urine samples containing a specific brand of drugs were collected. The collected urine samples without any dosage of drugs were spiked with a different concentration of analytes to construct a calibration set; therefore, the proposed method might be successfully used in the presence of matrix effects and unknown calibrated interferences in human urine using first-order data. In this method, a smaller number of calibration samples were used as compared to first-order multivariate calibration methods. Despite intense spectral overlapping and the presence of interferents in the test samples, the results indicated good analytical performance towards the analytes. By calibrating all present components in the unknown samples and imposing the known values in calibration samples during iterations as a correlation constraint, accurate concentrations of the analytes in the unknown set could be predicted. The maximum and minimum band boundaries of feasible solutions corresponding to the species profiles were estimated. The proposed method was used to determine ternary and quaternary mixtures of drugs in urine samples.
    Keywords: MCR-ALS, Ternary mixture of drugs, Quaternary mixture of drugs, First order data, Human urine
  • Alireza Ghiasvand, Afagh Nasirian, Samira Koonani, Kolsoom Nouriasl Pages 105-126
    Since solid-phase and liquid-phase microextraction (SPME and LPME) were introduced, as effective solvent-free methods, many efforts have been made to improve their modes and applications. However, due to limitations with sensitivity and efficiency, researchers have focused on improving the performance of their basic primary modes. In this way, in recent years, different methods such as ultrasonic-assisted microextraction (UA-ME), microwave-assisted microextraction (MA-ME), solvent-assisted microextraction (SA-ME) and cooling-assisted microextraction (CA-ME) were developed to reinforce the efficiency of the SPME and LPME methods. These strategies make the microextraction methods more effective and applicable, to different sample matrices. In this article UA-ME and CA-ME, as the most important methods to enhance the efficiency of SPME and LPME, were reviewed and their different aspects were evaluated and compared. Comparison of different microextraction reinforcement approaches revealed that the CA-ME is the most effective method to increase the extraction efficiency, especially for the analysis of complicated solid matrices.
    Keywords: Ultrasonic, assisted microextraction, Cooling, assisted microextraction, Solid, phase microextraction, Liquid, phase microextraction
  • Maryam Koohsarian, Ali Mokhtari * Pages 127-139
    A simple and sensitive chemiluminescence (CL) method was developed for direct quantification of oxymorphone, a µ opioid agonist that is approximately 10 times more potent than morphine. In this method potassium permanganate in polyphosphoric acid was used as CL reagent. Using this method, oxymorphone can be determined over the concentration ranges 13.5-337.8 ng mL-1 and 0.34-6.76 µg mL-1 with a sampling rate of 45 samples h−1. The limit of detection was 3.5 ng mL-1 (signal to noise =3) and the percent of relative standard deviations (in 9 replicate measurements) were 3.1% for 135.1 ng mL-1 and 3.6% for 1.4 µg mL-1 oxymorphone. The method is applied to human plasma and synthetic samples. The CL mechanism has been proposed using UV-Vis, fluorescence and CL spectra. In this study, detectability of oxymorphone in some other CL systems such as Ce(IV)-H2SO4, luminol-H2O2, Ru(phen)32+-Ce(IV) and permanganate-SO32- is investigated. CL intensities of twelve narcotics or related drugs were also investigated in the proposed CL system.
    Keywords: Chemiluminescence, Oxymorphone, Potassium permanganate, Polyphosphoric acid
  • Maryam Ghaemi *, Ghodratollah Absalan, Tayebe pourshamsi Pages 141-154
    CoFe2O4 magnetic nanoparticles were modified by dopamine (DA) and ascorbic acid (AA) as anchors. Separation of the DA and AA using CoFe2O4 magnetic nanoparticles have been studied by investigating the effects of pH, concentration of the DA and AA, amount of adsorbents, contact time, ionic strength and temperature. The mechanism of adsorption was also studied. The adsorption of DA and AA to the CoFe2O4 magnetic nanoparticles could be described by Langmuir-type adsorption isotherms. The effective surface area of the CoFe2O4 nanoparticles was 53.55 m2/g and 109.81 m2/g, respectively, for DA and AA. The maximum adsorption capacities were 28.98 and 72.99 mg of enediol per gram of adsorbent for DA and AA, respectively. With the help of adsorption isotherm, thermodynamic parameters such as free energy, enthalpy, and entropy have been calculated. The adsorption of DA onto CoFe2O4 is exothermic, but the temperature effect was negligible for adsorption of AA. On the basis of pseudo-first-order and pseudo-second-order kinetic equations different kinetic parameters have been obtained. DA and AA can be desorbed from the CoFe2O4 using concentrated imidazole as an eluent.
    Keywords: Magnetic nanoparticle, Adsorption, Dopamine, Ascorbic acid
  • Biuck Habibi *, Zahra Ayazi, Maryam Dadkhah Pages 155-169
    In the present work, an efficient modified carbon-ceramic electrode by multi-walled carbon nanotubes/ionic liquid nanocomposite (MWCNTs/IL/CCE) was prepared through a simple and repeatable procedure. The introduced modified electrode was used for the study of the electrochemical behaviour and determination of tryptophan (Trp) in the presence of uric acid (UA) using cyclic voltammetry (CV), differential pulse voltammetry (DPV) and amperometry techniques. The MWCNTs/IL/CCE exhibited high electrocatalytic activity toward the oxidation of Trp in phosphate buffer solution (pH 7.0) which led to produce an anodic peak at about 0.67 V vs. saturated calomel electrode. The influential parameters such as pH, amount and ratio of MWCNTs/IL in the nanocomposite modifier on the electrocatalytic activity of the MWCNTs/IL/CCE were studied and optimized. Under the optimum conditions, the anodic peak current in DPV method is linear for the Trp concentrations in the ranges of 5×10-7 M to 7×10-5 M with a correlation coefficient of 0.998 and detection limit of 3.2×10-7 M (S/N=3). The relative standard deviation of the anodic peak current obtained for a 5.0×10-5 M Trp solution was 2.2% (n=6). Finally, DPV method was applied for simultaneous determination of Trp and UA, which demonstrates the applicability of the present modified electrode.
    Keywords: Multi-walled carbon nanotubes, Ionic Liquid, Nanocomposite, tryptophan, Uric Acid, Simultaneous determination, Modified electrode
  • Salma Jadali, S. Maryam Sajjadi *, Hassan Zavvar Mousavi, Maryam Rajabi Pages 171-187
    In this study, the ashes of poplar tree leaves are applied as an efficient, accessible and inexpensive biosorbent for the removal of heavy metals Pb2+ and Cu+2 in aqueous solutions. In the adsorption processes, the success of the ions removal highly depends on the level of several experimental factors such as pH, contact time, adsorbent dosage and temperature. Therefore, a genuine statistical experiment design method is required to achieve a common experimental conditions where both ions have been removed from aqueous solutions to a great degree. Here, this common optimal conditions are obtained by the combination of experimental design and desirability function methods. For a mixture of Pb2+ and Cu+2, the following optimal conditions were achieved: pH of 5.4, contact time of 23 min, adsorbent dosage of 0.14 g, and temperature of 280C; at 150 mg L-1 of Pb2+ and 120 mg L-1 Cu2+. The removal efficiencies of Pb2+ and Cu+2 were 92.8% and 94.9%, respectively, which verified the applicability of this biosorbent for the ions removal. Moreover, the equilibrium and kinetic behavior of the adsorption processes are investigated and then thermodynamic parameters, ΔG0(Kj mol-1), ΔH(Kj mol-1)0, and ΔS0 (Kj mol-1), are evaluated which reveal that both processes are endothermic and spontaneous.
    Keywords: Desirability function, Biosorption, heavy metals, Kinetic, thermodynamic parameters