Mohammad Mirzaei

Simultaneous separation/preconcentration of ultra trace heavy metals in industrial wastewaters by dispersive liquid-liquid microextraction based on solidification of floating organic drop prior to determination by graphite furnace atomic absorption spectrometry.

In the present work, an efficient microextraction method was applied to separation and preconcentration of Ni(II), Co(II), Pb(II) and Cr(III). This method is dispersive liquid-liquid microextraction based on solidification of floating organic drop, which overcomes the most important problems of each aforementioned technique. The influences of analytical parameters, including pH, extraction solvent volume, disperser solvent type and its volume, concentration of chelating agent, salt effect and extraction time on the quantitative recoveries of nickel, cobalt, lead and chromium ions were investigated. Under the optimized conditions, the limits of detection were 0.2 ng L(-1) for Cr and 1.3 ng L(-1) for Co, Ni and Pb, with a preconcentration factor of 800 times. The relative standard deviations of 6.2% at 6.0 ng L(-1) of Cr and 7.2% at 10 ng L(-1) of Co, Ni and Pb were obtained (n=7). The proposed method was successfully applied for the analysis of ultra trace metals in water and wastewater samples.

A novel coating based on carbon nanotubes/poly-ortho-phenylenediamine composite for headspace solid-phase microextraction of polycyclic aromatic hydrocarbons

A novel nanocomposite coating made of poly-o-phenylenediamine (PoPD) and oxidized multiwalled carbon nanotubes (MWCNTs) was electrochemically prepared for the first time on stainless steel wire. Subsequently, it was applied to headspace solid-phase microextraction (HS-SPME) and gas chromatographic analysis of biphenyl and seven polycyclic aromatic hydrocarbons (PAHs). The effects of polymerization potential, polymerization time, concentration of o-phenylenediamine and oxidized MWCNTs were investigated on the coating process. The fiber coating was carried out easily and in a reproducible manner, and the produced fiber was stable at high temperatures. The surface morphology of the coating was examined by scanning electron microscopy (SEM). The effects of various parameters on the efficiency of HS-SPME process, such as desorption temperature, desorption time, extraction temperature, extraction time and ionic strength were also studied. Under optimized conditions, the calibration graphs were linear in the range of 0.1-300 ng mL(-1), and the detection limits for biphenyl and PAHs studied were between 0.02 and 0.09 ng mL(-1). The intra-day and inter-day relative standard deviations obtained at 5 ng mL(-1) concentration level (n=5), using a single fiber, were 3.2-7.8% and 5.2-9.3%, respectively. The fiber-to-fiber RSD% (n=3) were 6.2-11.3% at 5 ng mL(-1). The proposed HS-SPME method was successfully applied for the analysis of PAHs in water samples.

Emergence of a new focus of anthroponotic cutaneous leishmaniasis due to Leishmania tropica in rural communities of Bam district after the earthquake, Iran

Objectives  To describe a new emerging focus of anthroponotic cutaneous leishmaniasis (ACL) due to Leishmania tropica in rural areas of Dehbakry county, south‐eastern Iran, after the earthquake of 2003.

Preconcentration of organochlorine pesticides in aqueous samples by dispersive liquid–liquid microextraction based on solidification of floating organic drop after SPE with multiwalled carbon nanotubes

SPE joined with dispersive liquid-liquid microextraction based on solidification of floating organic drop (DLLME-SFO) as a novel technique combined with GC with electron-capture detection has been developed as a preconcentration technique for the determination of organochlorine pesticides (OCPs) in water samples. Aqueous samples were loaded onto multiwalled carbon nanotubes as sorbent. After the elution of the desired compounds from the sorbent by using acetone, the DLLME-SFO technique was performed on the obtained solution. Variables affecting the performance of both steps such as sample solution flow rate, breakthrough volume, type and volume of the elution, type and volume of extraction solvent and salt addition were studied and optimized. The new method provided an ultra enrichment factor (8280-28221) for nine OCPs. The calibration curves were linear in the range of 0.5-1000 ng/L, and the LODs ranged from 0.1-0.39 ng/L. The RSD, for 0.01 μg/L of OCPs, was in the range of 1.39-13.50% (n = 7). The recoveries of method in water samples were 70-113%.

Preparation and application of carbon nanotubes/poly(o-toluidine) composite fibers for the headspace solid-phase microextraction of benzene, toluene, ethylbenzene, and xylenes

A novel nanocomposite coating of poly(o-toluidine) and oxidized multiwalled CNTs (MWCNTs, where CNTs is carbon nanotubes) was electrochemically prepared on a stainless-steel wire. The applicability of the fiber was assessed for the headspace solid-phase microextraction of benzene, toluene, ethylbenzene, and xylenes in aqueous samples followed by GC with flame ionization detection. In order to obtain an adherent and stable composite coating, several experimental parameters related to the coating process, such as polymerization potential and time, and the concentration of o-toluidine and oxidized MWCNTs were optimized. The combination of MWCNTs and polymer in a nanocomposite form presents desirable opportunities to produce materials for new applications. The effects of various parameters on the efficiency of the headspace solid-phase microextraction process, such as desorption temperature and time, extraction temperature and time, and ionic strength were also investigated. At the optimum conditions, LODs were 0.03-0.06 μg/L. The method showed linearity in the range of 0.5-300 μg/L with coefficients of determination >0.99. The intraday and interday RSDs obtained at a 5 μg/L concentration level (n = 5) using a single fiber were 1.2-5.2 and 3.2-7.5%, respectively. The fiber-to-fiber RSD (%; n = 3) at 5 μg/L was 6.1-9.2%.

Prevalence, predilection sites and pathological findings of Taenia multiceps coenuri in slaughtered goats from south-east Iran

Coenurosis is a zoonotic disease in a variety of ruminants caused by the metacestode of Taenia multiceps. The coenuri in the brain and spinal cord of sheep and goats have been identified as Coenurus cerebralis whilst those reported in other tissues have been named Coenurus gaigeri. This study was conducted during the spring and summer of 2011. Out of 25 739 goats inspected in slaughterhouses, 23 carcasses (0.09%) revealed one or multiple visible swellings on the different muscles and visceral organs. The coenuri, of variable sizes, were found mainly in the muscles of the thigh, shoulder and neck, and were less common in the abdominal muscles and subcutaneous tissues. Coenuri were also found in the diaphragm, tongue, intercostal muscles, lung, parotid area and tunica adventitia of the aorta in a goat with severe infection. The brains of slaughtered goats that had coenuri in their skeletal muscles were examined and coenuri were found in two specimens (8.69%). The coenuri were located in the occipital lobe, the anterior part of the right cerebrum and the parietal lobe of the left cerebrum. Histopathologically, coenuri in the brain caused pressure atrophy and liquefactive necrosis in the surrounding tissues, hyperaemia, perivascular cuffing, neuronal degeneration, neuronophagia, satellitosis, diffuse microgliosis and astrocytosis. Coenuri in the skeletal muscles caused degenerative and necrotic changes, hyalinisation and myositis. In the lung, tissues around the coenurus revealed atelectasis and focal interstitial fibrosis. In the present study, concurrent occurrence of coenuri in the central nervous system and skeletal muscles supports the hypothesis that C. cerebralis and C. gaigeri are different names for the metacestodes of the same species of tapeworm.

Poly(o-anisidine)/graphene oxide nanosheets composite as a coating for the headspace solid-phase microextraction of benzene, toluene, ethylbenzene and xylenes.

A poly(o-anisidine)/graphene oxide nanosheets (PoA/GONSs) coating is fabricated by a simple and efficient electrochemical deposition method on steel wire. The incorporation of PoA and GONSs allows preparing a nanocomposite that can successfully integrate the advantages of both. Then, the prepared fiber is applied to the headspace solid-phase microextraction (HS-SPME) and gas chromatographic analysis of benzene, toluene, ethylbenzene and xylenes. In order to obtain an adherent, stable and efficient fiber to extract target analytes, experimental parameters related to the coating process such as deposition potential, deposition time, concentration of the monomer and concentration of GONSs were studied. The prepared composite fiber were characterized by Fourier transform infrared spectroscopy, powder X-ray diffraction and scanning electron microscopy. The effect of various parameters on the efficiency of HS-SPME process consisting of desorption temperature and time, extraction temperature and time and ionic strength were also optimized. Under the optimal conditions, the method was linear for orders of magnitude with correlation coefficients varying from 0.9888 to 0.9993. Intra- and inter-day precisions of the method were determined from mixed aqueous solutions containing 5.0 ng mL(-1) of each BTEX. The intra-day precisions varied from 3.1% for toluene to 5.7% for ethylbenzene, while the inter-day precisions varied from 4.9% for o-xylene to 7.3% for m,p-xylene. Limits of detection were in the range 0.01-0.06 ng mL(-1). The proposed method was applied to monitor BTEX compounds in some water samples and the accuracies found through spiking river water samples showed high recoveries between 92.0 and 101.2%.

Electropolymerization of carbon nanotubes/poly-ortho-aminophenol nanocomposite on a stainless steel fiber for the solid-phase microextraction of phthalate esters

A nanoporous composite film of poly-o-aminophenol (PoAP) and oxidized multiwalled carbon nanotubes (MWCNTs), which is electrochemically co-deposited on a stainless steel wire, has been synthesized. It was used as a new coating for direct immersion solid-phase microextraction (DI-SPME) of phthalate esters in various aqueous samples. In order to obtain an adherent, smooth and stable film, experimental parameters related to the coating process were optimized. These parameters include mode of electropolymerization, potential range, scan rate, the number of cycles, concentration of the monomer and oxidized MWCNTs. The coating was highly stable and extremely adherent to the surface of the steel fiber. The effects of various parameters on the efficiency of the SPME process consisting of desorption temperature, desorption time, extraction time, extraction temperature, ionic strength and pH were also studied. Under optimized conditions, detection limits for the phthalate esters varied between 0.03 and 0.08 ng mL−1. The intra-day and inter-day relative standard deviations for various phthalate esters at 1.0 ng mL−1 concentration level (N = 7) using a single fiber were 4.1–11.1% and 4.6–12.5%, respectively. The fiber-to-fiber RSD% (N = 3) was 6.5–13.1% at 1.0 ng mL−1. The method was linear at three orders of magnitude with correlation coefficients varying from 0.9878 to 0.9995. The method was successfully applied to the analysis of bottled mineral water samples and three injectable infusion solutions with recoveries from 91 to 115%.

Prevalence of intestinal helminthes in owned dogs in Kerman city, Iran.

OBJECTIVE To survey the prevalence of canine gastrointestinal helminthes in dogs presented to the Veterinary faculty of the University of Kerman between May and November 2011. METHODS A total of 70 fecal samples were evaluated by the fecal sedimentation method. RESULTS The prevalence of gastrointestinal helminthes was 7.14%. The parasites most frequently detected were Toxocara canis (T. canis) (4.3%); Toxascaris leonina (T. leonina) (1.4%) and Teania spp. (1.4%). The age distribution of intestinal parasites in dogs showed that the dog less than 1 year old had a higher overall prevalence than those dogs over 12 months of age but there was not significant (P>0.05). Also there was no significant difference in the prevalence between male (7.7%) and female (6.5%) dogs (P>0.05). CONCLUSIONS It is thought that the reduction in the frequency of the dogs with those helminthes may be mainly a result of the improvement in breeding environment and the routine use of antihelmintics. The significance of zoonotic diseases caused by intestinal helminthes makes it necessary for us to know the infection status of domestic dogs and to take measures for further control. It is concluded that veterinarians have an important role in educating dog owners of these potential risks and means for preventing or minimizing zoonotic transmission.

Carbon nanotubes/poly-ortho-aminophenol composite as a new coating for the headspace solid-phase microextraction of polycyclic aromatic hydrocarbons

In this work, oxidized multiwalled carbon nanotubes/poly-ortho-aminophenol (MWCNTs/PoAP) composite was directly electrodeposited on the surface of a stainless steel wire as a new coating. It was applied to the headspace solid-phase microextraction (HS-SPME) of a group of polycyclic aromatic hydrocarbons (PAHs) and biphenyl from aqueous samples and determination by gas chromatography with mass spectrometry (GC-MS). The characteristics of the fiber coating were studied by scanning electron microscopy and Fourier transform infrared spectroscopy. To evaluate the coating, the influence of various parameters on PAHs and biphenyl extraction efficiency by HS-SPME was investigated. At the optimum conditions, the linearity of the method based on the MWCNTs/PoAP fiber were 0.05–20 ng mL−1 for naphthalene and pyrene and 0.01–20 ng mL−1 for other PAHs. In addition, the limits of detection (LODs) (S/N = 3) were 0.002–0.01 ng mL−1. The intra-day and inter-day relative standard deviations at 0.5 ng mL−1 concentration level (n = 5) using a single-fiber were from 4.7% to 9.3% and 6.4% to 10.1%, respectively. The fiber-to-fiber RSD% (n = 3) was between 7.1% and 12.5%. Finally, the development method was applied to the analysis of real samples.