A facile and sensitive coprecipitation method coupled with flame atomic absorption spectrometry for quantification of Cu(II) ions in complex matrices

In the present investigation, the application of an organic coprecipitant, 2-[5,6-dichloro-2-(2-bromobenzyl)-1H-benzimidazole-1-yl]acetohydrazide (DIBBA), for separation and preconcentration of Cu(II) ions in fruit and water samples through a new carrier element free coprecipitation (CEFC) method was researched for the first time. Flame atomic absorption spectrometer (FAAS) was used for the analyses of Cu(II) ions. The main effective experimental factors such as solution pH, DIBBA quantity, waiting time, centrifuge speed and duration and volume of sample on the recovery efficiency of Cu(II) ions were explored in detail. Under the optimized conditions the preconcentration factor (PF), relative standard deviation (RSD), and limits of detection (LOD) was achieved as 50, 3.4 % and 0.44 µg L-1, respectively. No interference effects were detected by virtue of the presence of various foreign ions. Satisfactory recoveries (in the range of 94.4 to 103.0 %) in the environmental sample matrix were acquired. After being validated the recommended selective, low cost, simple and rapid CEFC method by spike/recovery tests, it was properly implemented for the low levels detection of Cu(II) ions in sour cherry, mulberry, apple, and peach as fruit samples and stream and sea water samples without any significant matrix effects

Natural and H2SO4 modified plane sawdust as a low-cost adsorbent: Removal of anionic and cationic dyes from aqueous solutions

Natural and H2SO4-modified plane (Platanus orientalis L.) sawdust were used for the adsorptive removal of cationic methylene blue (MB) and anionic indigo carmine (IC) dyes from aqueous media to suggest a new and cost-effective method for wastewater treatment applications. The influences of initial pH values, concentrations of MB and IC, period of contact, dosages of the natural and modified plane sawdust, and the presence of foreign ions on the adsorption of dyes were investigated in the experimental studies to describe the best conditions of the most efficient adsorption processes. Initial pH values were optimized to be between 6.0–8.0 for MB and 2.0 for IC. Optimum contact time to reach the equilibrium were determined as 120 and 240 min for the adsorption of MB onto NPS and MPS, respectively while IC adsorption onto both adsorbents reached the equilibrium in 240 min. By using the Langmuir isotherm model maximum MB adsorption capacities of NPS and MPS were calculated as 55.56 and 38.46 mg/g, respectively and the maximum IC adsorption capacities were 58.82 and 55.55 mg/g for NPS and MPS, respectively. Results showed that the natural and H2SO4-modified plane sawdust serve as low-cost and efficient materials in the adsorptive removal of MB and IC dyes for industrial wastewater treatment applications

Adsorption Of Methylene Blue from Aqueous Solution with Sulfuric Acid Activated Corn Cobs: Equilibrium, Kinetics, and Thermodynamics Assessment

Three adsorbents with different characteristics were produced in this study by activation of sulfuric acid with different concentrations, from corn Zea mays L. cobs, which is an agricultural waste by-product resulting from harvesting. After characterization by the parameters such as Boehm titration, determination of pH-pHpzc, and methylene blue – iodine number, and IR analysis, their methylene blue adsorption potentials from aqueous medium were investigated based on equilibrium, kinetics, and thermodynamics evaluations. This study aims to examine the effects of relatively dilute and concentrated acids on the activation process and to gain an economic value to waste materials through the production of a new adsorbent. It was observed that the initial solution pH did not have a significant effect on the adsorption efficiency. The adsorption process reached the equilibrium at the end of the first 120 minutes, and the kinetic data fit the pseudo-second-order kinetic model. Langmuir adsorption capacity 295.5 mg/g of the adsorbent produced by activating with 50% sulfuric acid was found higher than those produced with 75% and 98% acids. An increase in ambient temperature effected the adsorption positively. As a result, in this study, very low-cost adsorbents were produced from the waste by-product corn cobs, and a new approach was proposed for cleaning wastewater containing dyestuffs

Post-intervention Status in Patients With Refractory Myasthenia Gravis Treated With Eculizumab During REGAIN and Its Open-Label Extension

OBJECTIVE: To evaluate whether eculizumab helps patients with anti-acetylcholine receptor-positive (AChR+) refractory generalized myasthenia gravis (gMG) achieve the Myasthenia Gravis Foundation of America (MGFA) post-intervention status of minimal manifestations (MM), we assessed patients' status throughout REGAIN (Safety and Efficacy of Eculizumab in AChR+ Refractory Generalized Myasthenia Gravis) and its open-label extension. METHODS: Patients who completed the REGAIN randomized controlled trial and continued into the open-label extension were included in this tertiary endpoint analysis. Patients were assessed for the MGFA post-intervention status of improved, unchanged, worse, MM, and pharmacologic remission at defined time points during REGAIN and through week 130 of the open-label study. RESULTS: A total of 117 patients completed REGAIN and continued into the open-label study (eculizumab/eculizumab: 56; placebo/eculizumab: 61). At week 26 of REGAIN, more eculizumab-treated patients than placebo-treated patients achieved a status of improved (60.7% vs 41.7%) or MM (25.0% vs 13.3%; common OR: 2.3; 95% CI: 1.1-4.5). After 130 weeks of eculizumab treatment, 88.0% of patients achieved improved status and 57.3% of patients achieved MM status. The safety profile of eculizumab was consistent with its known profile and no new safety signals were detected. CONCLUSION: Eculizumab led to rapid and sustained achievement of MM in patients with AChR+ refractory gMG. These findings support the use of eculizumab in this previously difficult-to-treat patient population. CLINICALTRIALSGOV IDENTIFIER: REGAIN, NCT01997229; REGAIN open-label extension, NCT02301624. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that, after 26 weeks of eculizumab treatment, 25.0% of adults with AChR+ refractory gMG achieved MM, compared with 13.3% who received placebo

Minimal Symptom Expression' in Patients With Acetylcholine Receptor Antibody-Positive Refractory Generalized Myasthenia Gravis Treated With Eculizumab

The efficacy and tolerability of eculizumab were assessed in REGAIN, a 26-week, phase 3, randomized, double-blind, placebo-controlled study in anti-acetylcholine receptor antibody-positive (AChR+) refractory generalized myasthenia gravis (gMG), and its open-label extension

Development of a new and facile carrier element-free coprecipitation procedure for separation, preconcentration and sensitive determination of Cu(II) and Cd(II) Ions in water and vegetable samples

A facile and sensitive method predicated on carrier element free coprecipitation (CEFC) using 2-(2-(2-(4-bromobenzyl)-1H-benzo[d]imidazole-1-yl)acetyl)-N-ethylhydrazine-1-carbothioamide (BIMANEC) is reported for trace determination of Cu(II) and Cd(II) in vegetables and water. BIMANEC was used for the first time for the quantitative determination of these trace heavy metals. Flame atomic absorption spectrometer (FAAS) was used for quantitation. The preconcentration conditions were optimized with respect to pH (8.0), BIMANEC mass (4.0 mg), volume of sample (100 mL), standing time (5 min), and centrifugation time and rate (3 min and 2500 rpm). The influence of potentially interfering ions was scrutinized for the recovery of analyte ions. Under the optimum conditions, the limits of detection (LODs) were 0.51 and 2.28 mu g L-1 for Cu(II) and Cd(II), respectively. The relative standard deviations were < 5% for both. The recoveries from the spiked vegetable samples were from 94.9 to 102.8% and from the spiked water samples between 93.2 and 101.6%. Consequently the developed new, facile, rapid, and highly efficient CEFC process was employed for the trace determination of Cu(II) and Cd(II)

Application of carrier element free coprecipitation (cefc) method for determination of co(II), cu(II) and ni(II) Ions in food and water samples

OZDES, Duygu/0000-0002-8692-2676WOS: 000322040900006PubMed: 23878931A simple and highly sensitive separation and preconcentration procedure, which has minimal impact on the environment, has been developed. The procedure is based on the carrier element free coprecipitation (CEFC) of Co(II), Cu(II), and Ni(II) ions by using 2-{4-[2-(1H-indol-3-yl)ethyl]-3-(4-methylbenzyl)-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl}-N'-(pyridin-2-yl methylidene)acetohydrazide (IMOTPA), as an organic coprecipitant. The levels of analyte ions were determined by flame atomic absorption spectrometry (FAAS). The detection limits for Co(II), Cu(II) and Ni(II) ions were found to be 0.40, 0.16 and 0.17 mu g L-1, respectively, and the relative standard deviations for the analyte ions were lower than 3.0%. Spike tests and certified reference material analyses were performed to validate the method. The method was successfully applied for the determination of Co(II), Cu(II) and Ni(II) ions levels in sea and stream water as liquid samples and red pepper, black pepper, and peppermint as solid samples.Unit of the Scientific Research Projects of Karadeniz Technical UniversityKaradeniz Teknik University [1156]Authors wish to thank the Unit of the Scientific Research Projects of Karadeniz Technical University (Project No: 1156) for the financial support

Assessment of Heavy Metal Contents of Mulberry Samples (Fruit, Leaf, Soil) Grown in Gumushane Province

Baltaci, Cemalettin/0000-0002-4336-4002WOS: 000458550500013The present study aims to identify the heavy metal contents of white mulberry (Morus albaL.) and black mulberry (Morus nigraL.) that are grown in the city center of Gumushane province and its neighboring counties. Heavy metal analyzes were performed in the fruits, leaves and soils of the plants. the control samples, on the other hand, were collected from the mulberry trees located 3km away from the highway where the vehicle traffic and industrial activities are at their lowest. Sample collection was performed twice ayear, namely during the ripening period and fully ripening period of the fruits.The analyses of the heavy metals were performed by using inductively coupled plasma-mass spectrophotometry (ICP-MS). the obtained results were compared with the acceptable limits of heavy metal for humans as established by the World Health Organization (WHO), Turkish Food Codex (TFC) and the literature and an opinion was submitted as to whether they present any risk in terms of human health. When the available data is evaluated, the mulberries grown in Gumushane province, were found to have presented ahealth risk in terms of Pb, Cd, Ni, Cu, Zn, Mn and Co metals.Research Council of the Gumushane University [:16, B0110.02.01]The authors wish to thank the Research Council of the Gumushane University (Project No:16.B0110.02.01) for the financial support of this study

Methylene blue adsorption onto drinking water treatment plant’s sludge and modeling by artificial neural network

Bu çalışmada içme suyu arıtma tesislerinde arıtım aşamaları sonucu oluşan İçme Suyu Arıtma Tesisi Atık Çamurunun (İSATAÇ), atık sularda organik kökenli bir kirletici (boyar madde) olan Metilen Mavisinin uzaklaştırılmasında adsorban olarak kullanılabilirliği araştırılmıştır. Adsorpsiyon çalışmalarında kullanılan İSATAÇ fiziksel ya da kimyasal ön işleme tabi tutulmamıştır. Öncelikle İSATAÇ’ın nem, yoğunluk, uçucu madde, sabit karbon, kül tayini yanı sıra elementel, SEM, FT-IR, XRD, XRF ve TGA/DTA analiz gibi çeşitli analitik işlemlerle karakterize edilmiştir. Sonrasında adsorpsiyon deneyleri kesikli sistemle gerçekleştirilmiş ve İSATAÇ’ın sulu çözeltiden bu kirletici türü uzaklaştırma potansiyeli denge, kinetik ve termodinamik parametreler açısından incelenmiştir. Metilen mavisinin uzaklaştırılmasında Langmuir izoterm modelinden elde edilen maksimum adsorplama kapasitesi 62,50 mg g-1 olarak tespit edilmiştir. Bazı deneysel parametrelerin İSATAÇ üzerinde Metilen Mavisi adsorpsiyonuna etkileri göz önüne alınarak Yapay Sinir Ağı (YSA) modeli geliştirilmiş ve İSATAÇ’ın atık sulardan organik kirleticilerin uzaklaştırılmasında kullanılabileceği sonucuna varılmıştır.In this work, it was investigated usability of Drinking Water Treatment Sludge (DWTS), obtained as end product at the end of treatment stages, as an adsorbent for removal of Methylene Blue, the organic pollutant (dyestuff), present in wastewaters. DWTS used for the adsorption experiments were not subjected to physical or chemical pre-treatment. Firstly, DWTS was characterized employing various analytical procedures including determination of moisture, density, volatiles, fixed carbon, ash, as well as elemental, SEM, FT-IR, XRD, XRF and TGA/DTA analysis. Then, adsorption experiments were carried out in a batch system and DWTS’s removal potential of the pollutant specie from aqueous solution was investigated in terms of equilibrium, kinetics and thermodynamics. DWTS’s maximum adsorption capacity obtained from Langmuir model for Methylene Blue was 62.50 mg g-1. Artificial Neural Network (ANN) model was developed considering the effects of certain experimental parameters for adsorption of Methylene Blue on DWTS and it was concluded that DWTS can be used to remove organic pollutants from wastewaters