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Protein misfolding is a biological process that leads to protein aggregation. Anomalous misfolding and aggregation of human superoxide dismutase (hSOD1) into amyloid aggregates is a characteristic feature of amyotrophic lateral sclerosis (ALS), a neurodegenerative illness. Thus, focusing on the L38R mutant may be a wise decision to comprehend the SOD1 disease process in ALS. We suggest that Bisdemethoxycurcumin (BDMC) may be a strong anti-amyloidogenic polyphenol against L38R mutant aggregation. Protein stability, hydrophobicity, and flexibility were altered when BDMC was bound to the L38R mutant, as shown by molecular dynamic (MD) simulations and molecular docking. FTIR data shows α-Helix dominance in BDMC-containing samples, with reduced β-sheet and disordered peaks, indicating the decrease of aggregate species. ThT aggregation kinetics curves show BDMC reduces L38R mutant aggregation dose-dependently, with higher BDMC concentrations yielding greater reductions. TEM images showed various quantities of amorphous aggregates, but notably, 60 μM BDMC markedly reduced aggregate density, underscoring BDMC's inhibitory effect. Hemolysis tests revealed aggregate species in BDMC-treated samples were less toxic than in L38R mutant samples alone at the same concentrations and exposure times. Overall, BDMC has substantial potential to develop highly effective inhibitors that mitigate the risk of fatal ALS., Competing Interests: Declaration of competing interest The authors declare that no conflict of interest exists for the present work., (Copyright © 2024 Elsevier B.V. All rights reserved.)

In this study, we scrutinized the degradation process of phoxim in the presence of Ag+ ions, maintaining a 1:1 molar ratio under diverse temperature conditions. Phoxim was chosen as the model compound to devise experimental methodologies that would shed light on the kinetic and degradation pathways within a time span of 0 to 184 min across varying temperatures. The Arrhenius equation was harnessed to ascertain the activation energies linked with the degradation of phoxim. The application of the Arrhenius equation enables the computation of the reaction constant at a given temperature, thereby paving the way for the prediction of phoxim concentrations at different temperatures. The second-order rate constant for the reaction was observed to lie within the range of 0.035 to 0.128 L mol-1min-1, and the half-life of the reaction fluctuated between 5.2 and 17 min across different temperatures.•The study investigates the degradation of phoxim in the presence of Ag+ ions at various temperatures.•The Arrhenius equation was used to calculate the activation energies and predict phoxim concentrations at different temperatures.•The second-order rate constant for the reaction ranged from 0.035 to 0.128 L mol-1min-1, with the half-life varying between 5.2 and 17 min., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 Published by Elsevier B.V.)

Tetracycline (TC), as a widely used antibiotic, is very useful in treating bacterial infections. However, its residues in animal foodstuffs can enter the human body through the food cycle and causes severe and chronic diseases. On the other hand, due to its weak non-biodegradability, it is considered a threat to the environment. In this regard, the development of sensing methods to detect and measure TC is need of the hour. Herein, a dual-emission fluorescence sensor based on porous aluminosilicate structure (ASS) with rough surface hexagonal shape morphology and pore diameter less than 2 nm was prepared. The porous AAS was modified by post-modification method with blue carbon dots (CDT) and rhodamine B (RB) as two fluorophores to develop the ratiometric fluorescence (RF) sensor (CDT-AAS/RB). Nanostructured CDT-AAS/RB emitted two resolved peaks at 445 and 585 nm , which were dramatically quenched in the presence of TC. The RF sensor, with excellent sensitivity, was able to measure TC over the linear range of 0.001-150 μM with a limit of detection of 5.4 nM in the aqueous phosphate buffer. Moreover, the AAS component granted high selectivity and anti-interference ability to the sensor. In addition, the stability of the sensor was greatly improved due to the non-accumulation of CDT nanoparticles and RB molecules in the presence of the AAS. The proposed method was able to determine TC in complex real samples with satisfactory recovery, and the obtained results were validated with standard high-performance liquid chromatography technique., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The presence of antibiotics in water sources is a significant concern due to their potential environmental impact and the risks to human health. In the present research, hierarchically mesoporous UiO-66 (HP-UiO-66) with a high surface area (1011 m 2 /g) and large pore volume was synthesized using the reflux method on the liter scale. The successful synthesis was confirmed by FT-IR, XRD, FESEM/EDS, N 2 -adsorption/desorption, and zeta potential techniques. The HP-UiO-66 was utilized to remove two large structure antibiotics, chlortetracycline hydrochloride (CTC), and oxytetracycline (OTC). Box Behnken design was used to investigate the factors affecting the removal process and the interactions between them. The maximum adsorption capacities for OTC and CTC antibiotics were 252.9 mg/g and 234.2 mg/g at 35 °C, respectively. The sum of the normalized error method was applied to the analysis of various error functions in the nonlinear fitting of equilibrium and kinetic data. The CTC and OTC adsorption kinetic followed a fractal-like pseudo-second-order model. The Langmuir isotherm fitted well to adsorption data. The results demonstrate that HP-UiO-66 can be used as a recyclable and efficient adsorbent for large molecule antibiotics removal., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Atropine is a tropane alkaloid found in abundance in Datura plant. We used two liquid-liquid extraction methods and magnet solid-phase extraction to compare the amount of atropine in these two types of plants (Datura innoxia and Datura stramonium). The surface magnetic nanoparticle Fe3O4 correction with an amine and dextrin, and finally, magnetic solid-phase extraction Fe3O4@SiO2-NH2-dextrin (MNPs-dextrin), was prepared. We determined the effect of significant parameters in the removal step and optimization of atropine measurements with half-fractional factorial design (25-1) and response surface methodology via central composite design. The optimum conditions are for desorption solvent = 0.5 mL methanol and desorption time of 5 min. We obtained an extraction recovery of 87.63% with a relative standard deviation of 4.73% via six frequented measurements on a 1 μg L-1 atropine standard solution based on the optimum condition. Preconcentration factors for MNPs are 81, limit of detection = 0.76 μg L-1 and limit of quantitation = 2.5 μg L-1., (© The Author(s) 2023. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Atropine (AT) is an anticholinergic drug. AT is abundantly in Datura plant seeds. Fe 3 O 4 @Zn/Mg MOF (Fe 3 O 4 @MOF) composite was synthesized. The compound had a high peroxidase-like activity in a chemiluminescence (CL) reaction. Addition of AT quenched CL. The linear range and limit of detection were 5-600 μg L -1 and 2 × 10 -2  μg L -1 . This method is fast, reversible, and selective, without biodegradability effects, high accuracy, and precision for measuring AT in the Datura plant., (© 2023 John Wiley & Sons Ltd.)

In this article; the bimetal metal-organic framework Zn/Mg (Zn/Mg MOF) is synthesized. Then Zn/Mg MOF bimetal was combined with Fe 3 O 4 and Fe 3 O 4 @SiO 2 , and composites of Fe 3 O 4 @ SiO 2 /MOF/Dextrin, Fe 3 O 4 @SiO 2 /MOF, Fe 3 O 4 @MOF/Dextrin and Fe 3 O 4 @MOF made. The peroxidase-like activity of these compounds was investigated and compared by calorimetric Resazurin (Rz) and O-phenylenediamine (OPD); (Rz-H 2 O 2 , OPD-H 2 O 2 ) and fluorimetric Rz and terephtalic acid (TA); (Rz-H 2 O 2 , TA-H 2 O 2 ). The Fe 3 O 4 @ MOF/Dextrin composite has the highest peroxidase-like activity. The effect factors (amount of pH (6), the values of TA (1.37 mM), H 2 O 2 (0.025 mM), reaction time (8.15 min), and amount of Composite (116.67 mg)) to increase the catalytic activity of Fe 3 O 4 @ MOF/Dextrin measured by chemometrics method. The most suitable linear range of the calibration curve by the TA-H 2 O 2 -Composite fluorimetric method is 1-600 μg L -1 , and the detection limit is 2.27 μg L -1 . The relative standard deviation (RSD%) for measuring concentration atropine 1 μg L -1 (n = 6) is 1.18%. Finally, from this system for measuring atropine extracted by the Liquid-liquid extraction (LLE) method in two types of plants, D. Innoxia north and west and D. stramonium north and west of Iran (118.25 μg L -1 , 79.80 μg L -1 ) and (18.477 μg L -1 , 9.27 μg L -1 ) used, respectively., (© 2023 The Authors.)

The development of efficient materials and methods for the elimination of heavy metals contamination from water bodies is increasingly demanded as these toxic cations can acute diseases to humans or make serious threat to the environment. The aim of this research is to evaluate the effectiveness of the organosilane coupling agent for the modification of hydrous manganese oxide and the application of the functionalized nanoadsorbent for the removal of nickel and copper ions from synthetic wastewater samples. The synthesized thiol-functionalized hydrous manganese oxide was characterized in terms of their morphology, surface area, functional groups, surface elemental compositions, and the structural properties. In the adsorption process of Ni(II) and Cu(II), the effective parameters including the initial metal cation concentration (20-150 mg/L), operation temperature (298-318 K), and the contact time at the optimum pH were investigated. The uptake of Ni(II) and Cu(II) ions on the prepared adsorbents followed by the Freundlich isotherm model reveals the heterogeneous adsorption, with the adsorption capacities of 24.96 mg/g and 31.2 mg/g for the modified adsorbent and 23.92 mg/g and 29.6 mg/g for the virgin adsorbent, respectively. Based on the results, both the virgin and the functionalized adsorbents exhibited high affinity to copper ions than nickel in the single-component system. Kinetic experiments of both metal ions clarified that the experimental data was well predicted by pseudo-second-order model and the equilibrium was achieved after 10 min of contact time. Additionally, the incorporation of the as-prepared adsorbents in the electrospun nanofibers membrane matrix showed the promising potential for the removal of metal cations. The nickel and copper removal efficiency by the membranes containing 1.5 wt% of the modified adsorbent was 80% and 89%, respectively which implying that the modified adsorbent could be employed more efficiently in other treatment techniques for the removal of metallic pollutants. The modification of hydrous manganese oxide by the functional mercaptosilane increases the adsorption sites for trapping the metal ions and improves the adsorption capacity, making high capability for the removal of metal ions from the effluent., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The development of efficient strategies for the removal of heavy metal ions from aqueous solutions is rapidly demanded as these contaminants are very toxic and carcinogenic and show detrimental effects on the living creatures. The main focus of the current study is on the preparation and assessment of electrospun adsorptive nanofiber membranes for the removal of toxic Ni(II) and Cu(II) from wastewater in the ultrafiltration process. Hydrothermally synthesized titanate nanotubes (TNT) was modified with thiol functional groups and then directly incorporated to the polyvinyl chloride nanofiber matrices via electrospinning process to fabricate an adsorptive membrane. The as-prepared electrospun nanofiber membranes and the nanoadsorbents were characterized with respect to the physiochemical properties, surface structure and morphology, applying XPS, FTIR, FESEM, EDX and TEM analysis and then, the membranes were evaluated in terms of the removal of the heavy metal ions in a continuous ultrafiltration mode. In adsorptive filtration of the metal ions, the effective factors including nanoadsorbents loading (0.5-1.5 wt%), initial metal ion concentration (60-150 mg/L), feed temperature (~25 °C-45 °C), presence of competing ion and reusability were investigated in the UF system where the membranes containing 1.5 wt% thiol-modified TNT and virgin TNT adsorbents demonstrated excellent removal efficiency compared to the other membranes. The Cu(II) and Ni(II) removal efficiency of the membrane containing 1.5 wt% functionalized TNT was 90% and 86.7%, respectively which was the highest ones. As was expected and due to the uniform dispersion and less aggregation of the modified TNT adsorbents on the large surface area of the electrospun nanofibers, more adsorption capacity of the nanoparticles can be exploited. Moreover, the strong affinity of the thiol functional groups toward the metal cations, these membranes removed metal contaminants more efficiently. Besides, the Cu(II) removal efficiency of the fabricated membranes didn't show any drastic changes in the presence of the competing ions. Furthermore, acceptable performance was achieved for the prepared membranes even after four adsorption/regeneration cycles in the continuous UF experiments, demonstrating the feasibility and effectiveness of the prepared adsorptive nanofiber membranes for the removal of heavy metal ions., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

In this work, Mn-doped ZnS quantum dots capped by L-cysteine (Mn@ZnS/L-cyst) and polyethylene glycol (Mn@ZnS/PEG) and also Mn-doped ZnS on zeolite NaY (Mn@ZnS/Y) were synthesized. These compounds were characterized by Fourier transform infrared (FT-IR), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), and ultraviolet-visible and fluorescence spectroscopy. Then, the photodegradation ability of these three photocatalysts was investigated for degradation of 4',5'-dibromofluorescein dye under ultraviolet irradiation. In the next stage, the different effective parameters on degradation performance, such as pH, catalyst dosage, and initial dye concentration, were studied. Results demonstrated that the optimum initial concentration was 40 mg L -1 for all three catalysts. The optimum catalyst dosage for both Mn-doped ZnS quantum dots capped by L-cysteine and Mn-doped ZnS on zeolite NaY was 0.017 g L -1 and for Mn-doped ZnS quantum dots capped by polyethylene glycol was 0.033 g L -1 . The degradation efficiency of 97% for all three photocatalysts was achieved; therefore, by considering the higher production yield of quantum dots onto zeolite and also the more convenient recovery of the Mn-doped ZnS on zeolite NaY from the solution, it seems synthesis of quantum dots onto the zeolites is a reasonable strategy.

In this work, a novel and highly fluorescent (FL) metal-organic framework (MOF)-based host-guest hybrid system was developed through encapsulation of polyethylene glycol (PEG)-capped ZnS quantum dots (QDs) into zeolitic imidazolate framework (ZIF)-67 at ambient temperature. This new composite material was characterized by FT-IR, XRD, TEM, UV-Vis absorption and FL spectroscopy, and then exploited as fluorescence sensor for highly sensitive and selective detection of Cu (II) ions in water samples. The as-prepared PEG-ZnS QDs@ZIF-67 nanohybrids took advantages of both accumulation effect in ZIF-67 and FL sensitivity and selectivity in ZnS QDs toward analyte-Cu 2+ . In this regard, ZIF-67 was treated as absorbents to capture and enrich Cu (II) ions, and ZnS QDs were exploited as tentacle to selectively and sensitively sense the bonding interactions between ZIF-67 and Cu (II) ions, and further transduce these chemical events to the detectable fluorescence signals. By this approach, Cu 2+ could be detected in a wide concentration range of 3 to 500 nM with a LOD as low as 0.96 nM. The proposed FL-sensor can be promising in the field of preparation of various QDs@MOFs platforms for application in high-performance optical sensing., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Nanoparticles of cadmium selenide (CdSe) doped with europium, were synthesized as stabilizing agents using thioglycolic acid ligand. This method is based on the enhancing effect of CdSe quantum dots (QDs) doped with europium on chemiluminescence (CL) emission. This emission was generated by mixing CdSe QDs with manganese (II), iron (II) and chrome (II) sulfates as catalysts in the presence of hydrogen peroxide (H 2 O 2 ). The structural characteristics and morphology of these nanoparticles were investigated by scanning electron microscopy, Fourier transform infrared spectroscopy, ultraviolet-visible absorption spectroscopy, X-ray pattern and dynamic light scattering methods. The CdSe QDs doped with europium were used as the sensitizer in a luminol-hydrogen peroxide CL system. The sensitized CdSe QDs were analyzed for antibacterial activity against Gram-positive or Gram-negative bacteria. The results showed that the CdSe QDs are effective against all the studied bacteria, effectiveness was especially higher for Bacillus subtilis., (© 2019 John Wiley & Sons, Ltd.)

Monitoring and assessing toxic materials which are being released into the environment along with wastewater is a growing concern in many industries. The current research describes a highly sensitive and rapid method for the detection of toxic concentrations of heavy metals in aquatic environments. Water samples were collected from southern coasts of the Caspian Sea followed by screening of luminescent bacteria. Phylogenetic analysis, including gene sequence of 16S rRNA, and biochemical tests were performed for identification of the isolate. Luminescence activity was tested and measured after treatment of the isolate with different concentrations of heavy metals and reported as EC 50 value for each metal. A luminous, gram negative bacterium with the shape of a curved rod was isolated from the Caspian Sea. Biochemical tests and 16S rRNA gene sequence analysis indicated that the isolate MM1 had more than 99% similarity to Vibrio campbellii. The novel isolate is able to emit high levels of light. Bioluminescence inhibitory assay showed that the Vibrio sp. MM1 had the highest sensitivity to zinc and the lowest sensitivity to cadmium; EC 50 values were 0.97mgl -1 and 14.54mgl -1 , respectively. The current research shows that even low concentrations of heavy metals can cause a detectable decline in luminescence activity of the novel bacterium Vibrio sp. MM1; hence, it makes a good choice for commercial kits for the purpose of monitoring toxic materials., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Objective: We aimed to assess the effects of obesity-related follicular fluid (FF) fatty acids (FAs) on the number and quality of oocytes, good embryo quality rate, and pregnancy rate., Materials and Methods: This prospective cohort study was conducted on 105 infertile women under the age of 38, who underwent intracytoplasmic sperm injection (ICSI) from March 2015 to October 2015. They were grouped into three body mass index (BMI) categories. The fatty acids composition of the FF was analyzed by GC-MS head space method. We studied the FAs correlation with BMI and ICSI outcomes., Results: The distribution of fatty acids did not differ significantly in each BMI group, with the exception for stearic that was marginally significant (p=0.05). The mean number of mature oocytes did not differ significantly between the BMI groups, the percent of Metaphase II (MII) oocytes was inversely associated with the BMI (r s =-0.21, p=0.03). Kruskal-Wallis test showed that the distribution of good quality embryos' percentages were different in at least two categories of studied BMI groups (p=0.009, p=0.02). The mean concentration of palmitic acid was higher in nonpregnant patients for all of the studied BMI classes (p=0.02, p=0.03, p=0.05), however, stearic (p<0.001) and linolenic acids (p=0.01) were higher in nonpregnant normal weight patients., Conclusion: Differences in BMI are not associated with the fatty acid composition of the FF. The FF fatty acid possibly affects the outcome of ICSI through the achievement of clinical pregnancy. Therefore, it is essential to provide patients with nutritional counseling before they use assisted reproductive techniques., (Copyright © 2017. Published by Elsevier B.V.)

Background: Our objective was to determine the effect of fatty acids (FAs) in serum and follicular fluid (FF) on fertilization and intracytoplasmic sperm injection (ICSI) outcomes., Methods: One hundred five women aged 18-38 years undergoing ICSI were recruited in this prospective cohort study. oocyte and emberyo quality was morphologically assessed. FAs in serum and FF were analyzed, using gas chromatography-mass spectrometry (GC-MS)., Results: The mean number of mature oocytes was associated with serum levels of oleic acid (r = 0.58; P = 0.002). There were negative correlations between metaphase II oocytes and FF levels of stearic acid (r = -0.19; P = 0.04) and linolenic acid (r = -0.37; P = 0.004). According to the obtained Spearman's correlation coefficients, serum levels of stearic, palmitoleic and tricosanoic acids were positively correlated with the percent of germinal vesicle (GV) stage oocyte. The mean serum level of eicosapentaenoic acid was significantly higher in pregnant women than in non-pregnant patients (P = 0.006). Good quality embryos' percentages were negatively correlated with the concentrations of palmitic acid (r = -0.22; P = 0.02). After adjusting the effects of body mass index and age, total FAs were found to have a significant effect on the odds of having high-quality oocytes (percentage of oocytes > 80%; odds ratio =2.55; P = 0.054)., Conclusion: Particular FAs affect oocyte maturation and implantation. Apparently, while higher FF levels of saturated FAs, especially palmitic and stearic acids, observed in some metabolic contexts have harmful effects on oocyte maturation and implantation, such effects can be counteracted and developmental competence can be enhanced (at least in vitro) by the presence of unsaturated FAs, e.g. oleic and eicosapentaenoic acids.

Borage (Echium amoenum fisch) is one of the most commonly used medicinal plants, and has long been used as a traditional herbal medicine for many (non)infectious diseases in Iran. Study on photoredox and photoimmunology of borage is little. Natural immunomodulatory plants with minimal adverse/toxic effects could help boost animal health and, ultimately, public health. To determine the effect of borage on the functions of key circulating innate immune cells, effects of borage extract (BE) on bovine neutrophils (PMN) photoredox and phagocytosis events were evaluated using an in vitro model system. Blood PMN isolated from healthy high yielding dairy cows (n = 8/treatment) were pre-incubated with BE and the impact on phagocytosis-dependent-and-independent cellular chemiluminescence (CL), phagocytosis, killing of Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), fluorescence-based PMN H2O2 production and necrosis were assessed. Relative to control (no BE) PMN, treatment with BE significantly increased phagocytosis-dependent-and-independent PMN CL (>10-15% increase). While BE also led to increased PMN H2O2 production, necrosis was also surprisingly higher in these cells. Phagocytosis and killing of both E. coli and S. aureus by PMN treated with BE was substantially higher than that by control PMN. The increased photoimmunobiological events especially intracellular CL, intracellular H2O2 formation, and phagocytic capacity of BE-treated PMN support the potential immunotherapeutic implications of borage and its components for particularly immunocompromised animals and humans., (Copyright © 2015 Elsevier B.V. All rights reserved.)

The effects of six synthetic imidazolium-based ionic liquids (ILs) on the Cu(II)-catalyzed chemiluminescence of lucigenin (Luc-CL) in the pH range 6.0-11 were investigated. Preliminary experiments found that the CL emission was strongly enhanced or inhibited in the presence of the ILs. The degree of enhancement or inhibition of the CL intensity in the presence of each IL was related to the molecular structure of the IL, the medium used, and the pH. The maximum enhancement of the CL intensity was observed at pH 9.0 (amplification factor = 443). This decrease in the pH at which maximum CL enhancement occurred and the substantial signal amplification of the Luc-CL may be related to a strong interaction between Cu(II) and the imidazolium ring of superior ILs at this pH. Additionally, the formation of IL microdomains in semi-aqueous media permitted more solubility of the product yielded by the Luc-CL reaction (N-methylacridone), which could increase the CL intensity. To obtain consistent data on the catalytic efficiency of Cu(II) in the presence of various ILs as well as the corresponding CL emission intensities, fluorescence quantum yields (Φ F) of lucigenin were measured under the same conditions. Comparison of the data pointed to the mechanism that controls the properties of Luc-CL in the presence of the Cu(II)/IL complexes. Based on the catalytic effect of the Cu(II)/IL complex and the measurement of the enzymatically generated H2O2, a novel, simple, and sensitive CL method for determining glucose with a detection limit (LoD) of 6.5 μM was developed. Moreover, this method was satisfactorily applied to the determination of glucose in human serum and urine samples. Graphical Abstract The lucigenin chemiluminescence assay for H2O2 and glucose using imidazolium-based ionic liquid derivatives/Cu(II) complexes as efficient catalysts at pH 9.0.

A novel fluorescence (FL) method using water-soluble CdSe quantum dots (QDs) is proposed for the fluorometric determination of hydrogen peroxide and glucose. Water-soluble CdSe QDs were synthesized by using thioglycolic acid as stabilizer in aqueous solutions. The nanoparticles were structurally and optically characterized by X-ray powder diffraction (XRD), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), UV-Vis absorption spectroscopy, photoluminescence (PL) emission spectroscopy and transmission electron microscope (TEM). Ionic liquid-sensitized effect in aqueous solution was then investigated. In the presence of ionic liquid as catalyst, H2O2 was decomposed into radical that could quench the fluorescence of CdSe QDs more efficiently and rapidly. Then the oxidization of glucose by glucose oxidase was coupled with the fluorescence quenching of CdSe QDs by H2O2 producer with ionic liquid catalyst, which can be used to detect glucose. Therefore, a new FL analysis system was developed for the determination of glucose. Under the optimum conditions, there is a good linear relationship between the relative PL emission intensity and the concentration of glucose in the range of 5.0×10(-7)-1.0×10(-4) M of glucose with a correlation coefficient (R(2)) of 0.9973. The limit of detection of this system was found to be 1.0×10(-7) M. This method is not only simple, sensitive and low cost, but also reliable for practical applications., (Copyright © 2015. Published by Elsevier B.V.)

In this study, a simple, rapid and sensitive luminol-CuO nanoparticles-H2O2 chemiluminescence (CL) method has been proposed for determination of glucose and cholesterol in plasma. Response surface methodology (RSM) based on Box-Behnken design (BBD) was used to optimize the most important operating variables (solution pH effect and the CL reagents concentration) of luminol CL system. In optimum conditions, it was found that CuO nanoparticles (NPs) could enhance the CL intensity and the method sensitivity towards evaluation of trace amount of glucose and cholesterol. Under the optimal conditions, there is a good linear relationship between the luminol-CuO NPs - H2O2 relative CL intensity and the concentration over the range of 1.2 × 10(-6)-1.0 × 10(-3) M (R (2)  = 0.9991) for glucose and 2.5 × 10(-5)-CuO NPs7.17 × 10(-3) M (R (2)  = 0.9968) for cholesterol and with a 3σ detection limit of 7.1 × 10(-7) and 6.4 × 10(-6) M, respectively. The relative standard deviations (RSD) < 3.3% were obtained.

A new sensitive chemiluminescence (CL) procedure for the detection of hexythiazox (HXTZ) is presented, based on the quenching effect of the HXTZ in the luminol-H2O2 system using gold nanoparticles (GNPs) as a catalyst. The Box-Behnken design matrix and response surface methodology (RSM) have been applied in designing the experiments for studying the interactive effects of the three most important variables pH, luminol, and H2O2 concentrations on the CL intensity of luminol catalysed by GNPs. Under the optimal conditions, the CL intensity was linear with HXTZ concentration in the range of 0.017-0.42 μg mL(-1), and the limit of detection (LoD) was 0.011 μg mL(-1). The procedure has been successfully applied to the detection of HXTZ residues in citrus fruits and water samples at trace levels. Mean recoveries obtained were between 84.0% and 95.3%, with a repeatability precision of <6%. Meanwhile, the possible mechanism of the inhibited CL intensity was discussed., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

We report herein the development of a novel chemiluminescence system based on simultaneous introducing of synthetic coumarin derivatives and chitosan-induced Au/Ag alloy NPs on the luminol CL system and suggest how it may be useful for determination of glucose. Chitosan-induced Au/Ag nanoalloys in the coumarin derivatives intensified-luminol CL system, in addition to catalyze CL reaction can make a change in the process of coumarin derivatives effect as fluorophore on the luminol CL system. This phenomenon is caused by interaction between active functional groups of coumarin derivatives and chitosan. The interaction strength depends on the coumarin derivatives' structure and their substituents. Considering the inevitable trend luminol radical and superoxide anion radical to absorption on the surface of the embedded Au/Ag nanoalloy in the chitosan matrix, it can be concluded that chitosan acts as a platform for all reagents involved in the CL reaction including coumarin derivatives, Au/Ag nanoalloy and luminol, and electron-transfer taking place on it; Placing all chemiluminescent reagents together on the chitosan network can lead to a powerful CL due to increasing rigidity of CL system. The most efficient coumarin derivative on the Au/Ag nanoalloy-fluorophore-luminol-H2O2 CL system, in relation to interaction capability with chitosan' functional groups, was selected and the CL condition in presence of it was optimized. Whereas the glucose oxidase-mediated oxidation of glucose yields gluconic acid and H2O2, under optimum condition the most efficient CL system was applied to detection of glucose due to enzymatically production of hydrogen peroxide. The linear response range of 1.5 × 10(-6)-5.0 × 10(-3) M and the detection limit (defined as the concentration that could be detected at the signal-to-noise ratio of 3) of 7.5 × 10(-7) M was found for the glucose standards. Also, the developed method was successfully applied to determination of glucose in real serum and urine samples of diabetic patients and validated against colorimetric spectroscopy method.

Indolizine derivatives are of great interest as fluorescent emitters for peroxyoxalate chemiluminescence. The reaction of peroxyoxalates such as bis-(2,4,6-trichlorophenyl) oxalate (TCPO) with H2O2 can transfer energy to fluorescer via the formation of dioxetanedione intermediate. Four indolizine derivatives were used as a novel fluorescer in the chemiluminescence (CL) systems in this study. The relationship between CL intensity and the concentration of fluorescer, peroxyoxalate, sodium salicylate and hydrogen peroxide was investigated. Optimum conditions were obtained for four fluorescers and it was found that the indolizine can be used as an efficient green fluorescence emitter. Vitamin B6 induces a sharp decrease in the CL intensity of the TCPO-hydrogen peroxide-sodium salicylate system. A simple, rapid and sensitive CL method for the determination of vitamin B6 has been developed. The results showed a linear relationship between vitamin B6 concentration and peroxyoxalate CL intensity in the range 7.0 × 10(-8) -1.0 × 10(-4) . A detection limit of 2.3 × 10(-8) M and relative standard deviation (RSD) of < 4.5% were obtained., (Copyright © 2014 John Wiley & Sons, Ltd.)

A novel glucose biosensor based on the chemiluminescence (CL) detection of enzymatically generated hydrogen peroxide (H₂O₂) was constructed by one covalent immobilization of glucose oxidase (GOD) in glutaraldehyde-functionalized glass cell. In following, chitosan-induced Au/Ag nanoparticles dispersed in ion liquid (IL) were synthesised and immobilized on it. Herein, chitosan molecules acted as both the reducing and stabilizing agent for the preparation of NPs and also, as a coupling agent GOD and Au/Ag alloy NPs. In addition to catalyze luminol CL reaction, these NPs offered excellent catalytic activity toward hydrogen peroxide generation in enzymatic reaction between GOD and glucose. The used IL in fabrication of biosensor increased its stability. Also, IL alongside Cu(2+) accelerated enzymatic and CL reaction kinetic, and decreased luminol CL reaction optimum pH to 7.5 which would enable sensitive and precision determination of glucose. Under optimum condition, linear response range of glucose was found to be 1.0 × 10(-6)-7.5 × 10(-3)M, and detection limit was 4.0 × 10(-7)M. The CL biosensor exhibited good storage stability, i.e., 90% of its initial response was retained after 2 months storage at pH 7.0. The present CL biosensor has been applied satisfactory to analysis of glucose in real serum and urine samples., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Objectives: Eriobotrya japonica belongs to the Rosaceae. Studies have shown that the flowers of this plant are rich in phenolic and flavonoid compounds. Accorrdingly, the evaluation of antioxidative effects of Eriobotrya japonica Flower Extract (EJFE) have been performed in vitro., Material and Methods: In this study, to investigate the influences of components of EJFE on its antioxidative activity, extract was prepared using hydro-alcoholic (25:75 V/V) solvent and the antioxidative activity of the extract was evaluated based on the scavenging of various radicals (DPPH and H2O2) by spectrophotometric method and chelating of ferrous ions by ferrozine reagent., Results: HPLC analysis of the Eriobotrya japonica Flower Extract (EJFE) revealed hesperetin and gallic acid as the major antioxidants. When the content of total flavonoid and polyphenolic compounds in the flower extract of this plant was examined, a significantly higher level of total polyphenols was found in Eriobotrya japonica flower extract., Conclusion: RESULTS demonstrate that the high ability to scavenge free radicals, reducing power, and Fe(+2)chelating activity exerted by the EJFE were due to the high content of hesperetin and gallic acid in the flowers.

A novel chemiluminescence (CL) method using water-soluble Mn-doped ZnS quantum dots (QDs) as CL emitter is proposed for the chemiluminometric determination of folic acid in pharmaceutical formulation. Water-soluble Mn-doped ZnS QDs were synthesized by using L-cysteine as stabilizer in aqueous solutions. The nanoparticles were structurally and optically characterized by X-ray powder diffraction (XRD), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), UV-Vis absorption spectroscopy and photoluminescence (PL) emission spectroscopy. The CL of ZnS QDs induced by directly chemical oxidation and its ionic liquid-sensitized effect in aqueous solution were then investigated. It was found that oxidants, especially hydrogen peroxide, could directly oxidize ZnS QDs to produce weak CL emission in basic conditions. In the presence of 1,3-dipropylimidazolium bromide/copper a drastic light emission enhancement is observed, related to a strong interaction between Cu(2+) and the imidazolium ring. Therefore, a new CL analysis system was developed for the determination of folic acid. Under the optimum conditions, there is a good linear relationship between the relative CL intensity and the concentration of folic acid in the range of 1×10(-9)-1×10(-)(6) M of folic acid with a correlation coefficient (R(2)) of 0.9991. The limit of detection of this system was found to be 1×10(-)(10) M. This method is not only simple, sensitive and low cost, but also reliable for practical applications., (Copyright © 2013 Elsevier B.V. All rights reserved.)

The catalyzed luminol chemiluminescent reaction has received a great amount of attention because of its high sensitivity and low background signal which make the reaction an attractive analytical chemistry tool. The present study, introduces the beneficial catalytic effects of dinuclear Cu(II) complex [Cu2L2(TAE)]X2, where TAE=tetraacetylethane; L=N,N(')-dibenzylethylenediamine and X=ClO4 on the luminol chemiluminescent reaction as a novel probe for the determination of glutathione (GSH) and L-cysteine (CySH) in human serum and urine. The [Cu2L2(TAE)]X2 has exhibited highly efficient catalytic activity of luminol CL as an artificial peroxidase model at pH as low as 7.5 in water in the presence of H2O2⋅GSH and CySH can induce a sharp decrease in CL intensity from the [Cu2L2(TAE)]X2-catalyzed luminol system. Under the selected experimental conditions, a linear relationship was obtained between the CL intensity and the concentrations of GSH and CySH in the range of 1.0×10(-7)-1.0×10(-4) M, with detection limits (S/N=3) of 2.7×10(-8) and 6.8×10(-8) M and RSD<4.2% (n=7) for GSH and CySH, respectively., (Copyright © 2013 Elsevier B.V. All rights reserved.)

A novel chemiluminescence (CL) reaction, Benzodiazepines-H2O2-1-Ethyl-3-Methylimidazolium Ethylsulfate/copper, for determination of clonazepam and diazepam at nanogram per milliliter level in batch-type system have been described. The method relies on the catalytic effect of 1-Ethyl-3-Methylimidazolium Ethylsulfate/copper on the chemiluminescence reaction of Benzodiazepines, the oxidation of Benzodiazepines with hydrogen peroxide in natural medium. The influences of various experimental parameters such as solution pH, the ratio of 1-Ethyl-3 Methylimidazolium ethylsulfate concentration to copper ion, the type of buffer and the concentration of CL reagents were investigated. Under the optimum condition, the proposed method was satisfactorily applied for the determination of these drugs in tablets and urine without the interference of their potential impurities., (Copyright © 2013 Elsevier B.V. All rights reserved.)

It was found that silver/gold alloy nanoparticles enhance the chemiluminescence (CL) of the luminol-H2O2 system in alkaline solution. The studies of UV-Vis spectra, CL spectra, effects of concentrations luminol, hydrogen peroxide and silver/gold alloy nanoparticles solutions were carried out to explore the CL enhancement mechanism. Flutamide was found to quench the CL signals of the luminol-H2O2 reaction catalyzed by silver/gold alloy nanoparticles, which made it applicable for the determination of flutamide. Under the optimum conditions, the CL intensity is proportional to the concentration of the flutamide in solution over the range 5.0 × 10(-7) to 1.0 × 10(-4)mol L(-1). Detection limit was obtained 1.2 × 10(-8)mol L(-1)and the relative standard deviation (RSD) γ5%. This work is introduced as a new method for the determination of flutamide in commercial tablets. Box-Behnken experimental design is applied to investigate and validate the CL measurement parameters., (Copyright © 2013 Elsevier B.V. All rights reserved.)

In this article, a novel chemiluminescence method using water-soluble CdS quantum dots (QDs) as sensitizers is proposed for the chemiluminometric determination of epinephrine. The method is based on the quenching effect of epinephrine on the chemiluminescence emission generated by the mixing of CdS quantum dots (QDs) with hydrogen carbonate (HCO3(-)) in the presence of hydrogen peroxide (H2O2) in an alkaline medium. The optimization of variables influencing the chemiluminescence response of the method has been carried out by using experimental design. Under the optimal conditions, there is good linear relationship between the relative chemiluminescence intensity and the concentration of epinephrine over the range of 5 × 10(-9)-1 × 10(-6) molL(-1) with a 3σ detection limit of 5 × 10(-11) molL(-1). The method has been successfully applied to the determination of epinephrine in pharmaceutical formulation and the recovery test was done in human urine.

Background: Nesfatin-1 is a protein derived from a precursor molecule of the nucleobindin-2 gene, and acts as an anorexigenic peptide on food intake behavior, and its level isinfluenced by nutritional status, food composition [fat and carbohydrate (CHO)], and physical exercise., Objectives: The aim of this study was to investigate the effects of 6 weeks of treadmill running (at high intensity) program with and without zizyphus jujuba (high carbohydrate content) crud extraction on liver nesfatin-1, ATP, glycogen, and its plasma concentrations in female rats., Materials and Methods: Twenty-eight Wistar female rats (6-8 weeks old100-120 g of weight) were randomly assigned to saline-control (SC), saline-training (ST), zizyphus jujuba-control (ZJC), and zizyphus jujuba-training (ZJT) groups. Rats ran on a motor-driven treadmill at 35 m/min, 60 min/day, 5 days/week for 6 weeks. Animals received ZJ extraction and saline at the dose of 1.25 mL/100g of body weight. Seventy-two hours after the last training session rats were killed, a portion of liver excited, and plasma was collected for nesfatin-1, ATP, and glycogen measurements. A one-way ANOVA method, and Pearson correlation were employed. P < 0.05 was considered as significant., Results: A higher and significant liver nesfatin-1 level was found in ZJ groups (p < 0.005), but plasma nesfatin-1 responded differently. Changes in liver nesfatin-1 were accompanied with an increase in liver glycogen,but not ATP contents., Conclusions: The Findings indicate that higher liver nesfatin-1 and glycogen content by ZJ extraction might be due to the ZJ high CHO content, and it could be consideredas an anti-appetite herb.

A novel, simple, cheap, and high sensitivity batch chemiluminescent method for the determination of catecholamine drugs, epinephrine (E), dopamine (DA) and methyldopa (MD) at microgram levels in pharmaceutical formulations is described. The method is based on a chemiluminescence (CL) system arising from the reaction of bis(2,4,6-trichlorophenyl) oxalate (TCPO) with H₂O₂ in the presence of a novel fluorescer, furandicarboxylate, and is proposed as a new analytical method for the determination of catecholamines. The method is based on the inhibition of CL emission by DA and its enhancement by E and MD. Under optimal conditions, good linear ranges were obtained, 0.5 - 12.7, 0.06 - 1.83 and 0.069 - 3.52 μg/mL with detection limits of 0.30, 0.03 and 0.04 μg/mL (S/N = 3) for DA, E and MD, respectively. Moreover, a pooled-intermediate model was used to determine the kinetic parameters of CL with and without catecholamines and a possible CL mechanism was discussed.

Adsorption of phenolic compounds and chemical analysis of them from a local production cigarette (named by Farvardin cigarette) smoke have been investigated by using perlite filtration. In this research, the mainstream smoke was tested by three filtration methods: Perlite filter, Cambridge filter and general cigarette filter. Then the used filter was extracted by pure methanol as solvent. After that, the extracted solution was analysed by GC-MS. By this consideration, the phenolic derivatives such as phenol, hydroquinone, resorcinol, pyrocatechol, m-cresol, p-cresol and o-cresol were detected. The structure of the perlite filtration after absorption was studied by SEM. In addition, its chemical structure was investigated by XRD and XRF.

In this work, L-cysteine capped-ZnS quantum dots were synthesized in aqueous medium, and their interaction with some of the amino acids was studied with fluorescence spectra. The results demonstrated that histidine could effectively quench the Quantum dots emission more than other amino acids. Electron transfer process between the capping ligands and histidine was mainly responsible for the remarkable quenching effect of histidine, because according to the structure of histidine, it is the strongest acceptor among essential amino acids. Under optimum conditions, the quenched fluorescence intensity increased linearly with the concentration of histidine ranging from 1.33×10(-6) to 1.49×10(-4) mol L(-1). The limit of detection for histidine was 0.05×10(-7) mol L(-1)., (Crown Copyright © 2012. Published by Elsevier B.V. All rights reserved.)

Furan derivatives (synthesized and purified in organic laboratories) are a great interest as fluorescent emitters for peroxyoxalate chemiluminescence. Reaction of peroxyoxalates such as bis-(2,4,6-trichloro-phenyl) oxalate with H(2)O(2) can transfer energy to fluorophore via formation of dioxetanedione intermediate. Furan derivatives used as a novel fluorescer in this study which produces a blue light in the chemiluminescence systems. The relationship between the chemiluminescence intensity and concentrations of TCPO, sodium salicylate, hydrogen peroxide and the fluorescer has been investigated. The linear ranges for Furan derivatives were 0.25-5 × 10(-4) M and 0.1-5 × 10(-4) M (A and B compounds, respectively). Kinetic parameters for the peroxyoxalate-chemiluminescence were also calculated from the computer fitting of the corresponding chemiluminescence intensity/time profiles.

Complexation of a fluoroquinolone derivative (ciprofloxacin), L, and some amino acids has been studied using spectrofluorimetric method. Results indicated that ciprofloxacin have a greater tendency to form a 1:1 complex with aspartic acid and arginine than the other tested molecules. The fluorescence of ciprofloxacin exhibits quenching process while it has been titrated with these amino acids. Formation constant values (K(f)) for complex formed between ciprofloxacin and amino acids were also calculated. Thermodynamic parameters such as ΔG°, ΔH° and ΔS° were studied too. Possible reasons for the observed stability sequence were discussed based on the structures proposed for the resulting complexes. Besides the solution studies, solvatochromic properties of the ciprofloxacin are discussed by studying its spectra in a selection of different solvents., (Copyright © 2012 Elsevier B.V. All rights reserved.)

A novel glucose biosensor based on the chemiluminescence (CL) detection of enzymatically generated H(2)O(2) was constructed by the effective immobilization of glucose oxidase (GOD)/carbon-nanotubes (CNTs)/gold nanoparticles (GNPs) in nafion film on graphite support. The influences of various experimental parameters such as solution pH, the action time of the enzyme, interferents and the concentration of CL reagents were investigated. Carbon nanotubes and gold nanoparticles offer excellent catalytic activity toward hydrogen peroxide generation in enzymatic reaction between glucose oxidase and glucose, which would enable sensitive determination of glucose. Under the optimum condition, the linear response range of glucose was found to be 2.25 × 10(-6) to 1.75 × 10(-4 ) mol L(-1), and the detection limit (defined as the concentration that could be detected at the signal-to-noise ratio of 3) was 1.00 × 10(-6) mol L(-1). The CL biosensor exhibited good storage stability, i.e., 80% of its initial response was retained after 10 days storage at pH 7.0. The present CL biosensor has been used to determine the glucose concentrations in real serum and urine samples with satisfactory results., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Fourier transform infrared (FTIR) microspectroscopy can be considered to be a fast and non-invasive tool for distinguishing between normal and cancerous cells and tissues without the need for laborious and invasive sampling procedures. Gastric samples from four patients (age, 65±2 years) were analysed. Samples were obtained from the organs removed during gastrectomy and then classified as normal or cancerous. Classification was based on histopathological examinations at our institution. Formalin-fixed sections of gastric tissue were analysed by FTIR-microspectroscopy. To characterize differences between sections of normal and cancerous tissue, specific regions of the spectra were analysed to study variations in the levels of metabolites. To distinguish between two conditions (normal and cancerous), changes in the relative intensity of bands in the range 600-4000 cm⁻¹ were analysed. A FTIR spectral map of the bands in the region 2800-3100 cm⁻¹ and 900-1800 cm⁻¹ were created to analyse pathological changes in tissues. The limited data available showed that normal gastric tissue had stronger absorption than cancerous tissue over a wide region in the four patients. There was a significant decrease in total biomolecular components for cancerous tissue compared with normal tissue.

The adsorption of chromium compounds from solutions by a composite of polyaniline/poly ethylene glycol (PANi/PEG) was investigated in this study. Experiments were conducted in batch mode under various operational conditions including agitation time, solution pH, PANi/PEG dose and initial concentration of chromium salts. Results showed that concentration of PEG at synthesizing stage has a significant effect on the capacity of produced composite for removal of chromium. Morphologically, PANi/PEG composite is closely dependent on the concentration of PEG. Maximum removal of hexavalent chromium was experienced when 2g/L of PEG was used in synthesis of PANi/PEG. Removal of hexavalent chromium by PANi/PEG composite included surface adsorption and reduction reaction. The optimum pH was 5 and the equilibrium time for hexavalent chromium removal was about 30 min. Investigation of the isothermal characteristics showed that chromium adsorption by PANi/PEG composite was in high accordance with Langmuir's isotherm., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Quinoxaline derivatives are a great interest as fluorescent emitters for peroxyoxalate chemiluminescence. Reaction of peroxyoxalates such as bis-(2,4,6-trichlorophenyl) oxalate with H(2)O(2) can transfer energy to fluorophore via formation of dioxetanedione intermediate. Two quinoxaline derivatives used as a fluorophore in this study which produce a green light in the chemiluminescence systems. The relationship between the chemiluminescence intensity and concentrations of fluorophore, peroxyoxalate, sodium salicylate and hydrogen peroxide was investigated. Kinetic parameters for the peroxyoxalate-chemiluminescence were also calculated from the computer fitting of the corresponding chemiluminescence intensity/time profiles. It was found that the biphenylquinoxaline can be used as an efficient green fluorescent emitter.

The solvatochromism of dihydroxybenzene derivatives as probes in 18 solvents were investigated in the UV-vis spectra. The position, intensity and shape of absorption bands change with various solvent nature. These changes were rationalized by solvatochromic parameters such as alpha, beta, ET(30), DN and AN using multiple linear regression (MLR) method. The studied dihydroxibenzene derivatives show negative solvatochromism and the correlation coefficients of derived equations by MLR method were obtained in the range 0.974-0.996. The linear solvation energy relationship parameters of the backward regression were applied to the Kamlet and Taft equation for the interaction of these three probes and solvents. The best LSER equation for these three probes, and the LSER parameters of backward regression with their mean effects and the regression coefficient have been calculated.

The quenching effect of l-cysteine, l-methionine on strong chemiluminescence of bis(2,4,6-trichlorophenyl)oxalate-H(2)O(2) system in the presence of rhodamine 6G was studied. The chemiluminescence parameters were evaluated from computer fitting of the resulting intensity-time plots. These systems resulted in Stern-Volmer plots in the quencher concentration range of 4.0 x 10(-6) to 4.0 x 10(-5)M, with K(Q) values of 1.64 x 10(4) and 8.0 x 10(4)M(-1) for l-metionine and l-cysteine, respectively. Also, this study describes the employment of l-histidine as a highly potent signal enhancer in peroxyoxalate chemiluminescence in the presence of rhodamine 6G.

Zinc has antioxidative properties and plays an important role in scavenging reactive oxygen species. We hypothesized that in the absence of Zn, the possibility of increased oxidative damage exists that would contribute to poor sperm quality. Therefore, measurement of seminal Zn in the seminal plasma of males with a history of subfertility or idiopathic infertility is necessary and can be helpful in fertility assessment. The primary objective of the present study was to assess the relationship between Zn levels in seminal plasma with sperm quality in fertile and infertile men. Semen samples were provided by fertile (smoker [n = 17], nonsmoker [n = 19]) and infertile men (smoker [n = 15], nonsmoker [n = 21]). After semen analysis, concentrations of Zn, Mg, Ca, Na, and K in the seminal plasma of all groups were determined by atomic absorption spectroscopy. Element concentrations in seminal plasma of all groups were in the order Na > K > Ca > Zn > Mg. Fertile subjects, smoker or not, demonstrated significantly higher seminal Zn levels than any infertile group (P < .001). A trend was observed for a lower Zn levels in seminal plasma of smokers compared with nonsmokers. Seminal Zn in fertile and infertile (smokers or nonsmokers) males correlated significantly with sperm count (P < .01) and normal morphology of sperm (P < .001). There was a significantly positive correlation between seminal Zn with Ca (P < .01) and K (P < .01) levels in all specimens. In conclusion, poor Zn nutrition may be an important risk factor for low quality of sperm and idiopathic male infertility.

Effect of aliphatic amines and their concentration on fluorescence intensity of 4-methyl umbelliferone (4-MU) one of coumarin derivative were investigated. This compound has blue light emission under UV lamp in methanolic solution. Spectral investigation of 4-MU solution containing amine compounds showed lower intensity at 350-410 nm (quenching region) and higher intensity at 430-500 nm (enhancing region) as compared to pure methanolic solution of 4-MU. Fluorescence intensity at isoemitting point was independent from concentration of amines. The variation of fluorescence intensity could be used for determination of aliphatic amines in both quenching and enhancing region. Linear ranges for determination of amines in the quenching region were obtained from Stern-Volmer diagram of 4-MU. Determination of amines at fluorescence enhancing region using inverse fluorescence intensity against inverse amine concentration (bireciprocal plot) were investigated and related equations was also proposed.

The purpose of this study is to accesses the efficiency of removal of pesticide Mancozeb (Dithiocarbamates family) using different sorbents (synthetic zeolite type A, Humic Acid (HA) extracted from soil of Noshahr jungle in the north of Iran and mixture of them). The adsorption efficiency of the adsorbents was evaluated by Freundlich isotherms to select the best sorbent. The main effective parameters such as the amount of sorbents, pH, agitating time and concentrations of Mancozeb were tested. The results for 1.6 ppm of pesticide at pH=5 shows the optimum values 2, 0.75, 0.5 g for HA, zeolite NaA and mixture of them, respectively. The adsorption capacity decreases as pH increases and the adsorption effect for 0.1 g of sorbents at pH=5 were obtained in the order: (mixture of sorbents) > (synthetic zeolite type A) > (extracted Humic Acid).

The chemiluminescence arising from the reaction of bis(2,4,6-trichlorophenyl)oxalate (TCPO) with hydrogen peroxide in the presence of brightener 4,4'-bis{[4,6-bis(2-hydroxyethyl)amino-1,3,5-triazin-2-yl]amino}stilbene-2,2'-disulfonic acid-disodium salt (Triazinyl) has been studied. The influence of concentration of TCPO, hydrogen peroxide, Triazinyl, base catalysts and temperature on the resulting chemiluminescence was investigated. The kinetic parameters for the peroxyoxalate-chemiluminescence (PO-CL) of Triazinyl were evaluated from computer fitting of the resulting intensity-time plots. The activation energies, E(a), were evaluated from temperature dependence of the corresponding rise and fall rate constants.

The cDNA of a firefly luciferase from lantern mRNA of Lampyroidea maculata has been cloned, sequenced and functionally expressed. The cDNA has an open reading frame of 1647 bp and codes for a 548-residue-long polypeptide. Noteworthy, sequence comparison as well as homology modeling showed the highest degree of similarity with H. unmunsana and L. mingrelica luciferases, suggesting a close phylogenetic relationship despite the geographical distance separation. The deduced amino acid sequence of the luciferase gene of firefly L. maculata showed 93% identity to H. unmunsana. Superposition of the three-dimensional model of L. maculata luciferase (generated by homology modeling) and three dimensional structure of Photinus pyralis luciferase revealed that the spatial arrangements of Luciferin and ATP-binding residues are very similar. Putative signature of AMPbinding domain among the various firefly species and Lampyroidea maculata was compared and a striking similarity was found. Different motifs and sites have been identified in Lampyroidea maculata by sequence analysis. Expression and purification of luciferase from Lampyroidea maculata was carried out using Ni-NTA Sepharose. Bioluminescence emission spectrum was similar to Photinus pyralis luciferase.

The gene coding for beetle luciferase, the enzyme responsible for bioluminescence in over two thousand coleopteran species has, to date, only been characterized from one Palearctic species of Lampyridae. Here we report the characterization of the luciferase gene from a female beetle of an Iranian lampyrid species, Nyctophila cf. caucasica (Coleoptera:Lampyridae). The luciferase gene was composed of seven exons, coding for 547 amino acids, separated by six introns spanning 1976 bp of genomic DNA. The deduced amino acid sequences of the luciferase gene of N. caucasica showed 98.9% homology to that of the Palearctic species Lampyris noctiluca. Analysis of the 810 bp upstream region of the luciferase gene revealed three TATA boxes and several other consensus transcriptional factor recognition sequences presenting evidence for a putative core promoter region conserved in Lampyrinae from -190 through to -155 upstream of the luciferase start codon. Along with the core promoter region the luciferase gene was compared with orthologous sequences from other lampyrid species and found to have greatest identity to Lampyris turkistanicus and Lampyris noctiluca. The significant sequence identity to the former is discussed in relation to taxonomic issues of Iranian lampyrids.

The quenching effect of L-cysteine and L-methionine on strong chemiluminescence of bis-(2,4,6-trichlorophenyl)oxalate-H(2)O(2) system in the presence of 7-amino-4-trifluoromethylcumarin was studied. The chemiluminescence parameters were evaluated from computer fitting of the resulting intensity-time plots. Both systems resulted in Stern-Volmer plots in the quencher concentration range of 6.5 x 10(-5) to 5.2 x 10(-4)M with k(Q) values of 1.15 x 10(4) and 1.28 x 10(4)M(-1) for L-cysteine and L-methionine, respectively.

Oscillating chemical reactions are complex systems, involving a large number of chemical species. In oscillating chemical reaction, some species, usually a reaction intermediate, exhibit fluctuation in its concentration. In this report, visible oscillating chemiluminescence produced by the addition of luminol (3-aminophthalhydrazide) to the oscillating system of H2O2-KSCN-CuSO4-TMAOH was investigated using spectrofluorimetry method. The effects of ingredient concentration of the oscillating system and complexing agents like citric acid and cysteine on the behavior of the oscillating system were investigated. Moreover, the influence of nonaqueous solvents such as ethanol and ethylene glycol has been studied.