Trace determination of bisphenol-A in landfill leachate samples by dispersive liquid- liquid microextraction followed by high performance liquid chromatography

A simple, rapid and efficient sample pretreatment technique, termed dispersive liquid-liquid microextraction (DLLME), was developed as an extraction methodology to determine bisphenol-A (BPA), in landfill leachate samples prior to high performance liquid chromatography (HPLC)-ultraviolet detection. Some effective parameters, such as pH, extraction and disperser solvent type and their volumes, time of extraction and salt effect have been optimized using the one-factor-at-a-time approach. Under the optimum conditions, the preconcentration factor 25 was obtained from only 5 mL of the sample. The calibration graph was linear in the range of 5-500 µg L-1 with the detection limit of 1.5 µg L-1. The relative standard deviation (RSD) for ten replicate measurements of 20 µg L-1 of BPA was 2.5%. Finally, the method was successfully applied for the extraction and determination of BPA in some landfill leachate samples with a relative recovery of 98–109% and RSD less than 5%. KEY WORDS: Dispersive liquid-liquid microextraction, Bisphenol-A, Landfill leachate samples, High-performance liquid chromatography Bull. Chem. Soc. Ethiop. 2014, 28(3), 329-338.DOI: http://dx.doi.org/10.4314/bcse.v28i3.

Effect of pioglitazone therapy on high sensitive C-reactive protein and lipid profile in diabetic patients with renal transplantation; a randomize clinical trial

Background: Inflammation has a major role in disease lead to renal failure and diabetes mellitus, controlling inflammation in diabetic kidney receivers could decrease morbidity and mortality. Objectives: This study designed for evaluating the efficacy of pioglitazone on C-reactive protein and lipid profile in diabetic kidney transplant receivers. Patients and Methods: In this double blinded clinical trial, 58 diabetic renal transplant receivers, in first month after transplantation, randomized into two groups; receiving insulin and pioglitazone (15 mg tablet daily, group A); and insulin and placebo (group B). Blood pressure, weight, body mass index (BMI) and laboratory data compared in before and after 4-month treatment in two groups by SPSS. Results: Fifty-eight patients with mean age of 44.15 ± 2 years included. There were no significant difference between groups in demographic data and other baseline measured variables (P > 0.05).The mean weigh and BMI were slightly increased in group A and decreased in group B. The mean hs-CRP was decreased 4.82 mg/dL in group A and 1.93 mg/dL in group B (P = 0.007). The mean total serum cholesterol was significantly decreased 34 mg/dL in group A and 18.07 mg/dL in group B (P = 0.027). The mean serum HDL-C was significantly increased 13.31 mg/dL in group A and 5.89 mg/dl in group B (P < 0.001). Conclusions: Pioglitazone seems to be a safe drug for reducing serum lipids and CRP in kidney transplant receivers with diabetes mellitus in short term. Long term effect of this drug could be evaluated in future studies. Copyright © 2015 The Author(s)

Application of chitosan functionalized with 3,4-dihydroxy benzoic acid moiety for on-line preconcentration and determination of trace elements in water samples

Chitosan resin functionalized with 3,4-dihydroxy benzoic acid (CCTS-DHBA resin) was used as a packing material for flow injection (FI) on-line mini-column preconcentration in combination with inductively coupled plasma-atomic emission spectrometry (ICP-AES) for the determination of trace elements such as silver, bismuth, copper, gallium, indium, molybdenum, nickel, uranium, and vanadium in environmental waters. A 5-mL aliquot of sample (pH 5.5) was introduced to the minicolumn for the adsorption/preconcentration of the metal ions, and the collected analytes on the mini-column were eluted with 2 M HNO3, and the eluates was subsequently transported via direct injection to the nebulizer of ICP-AES for quantification. The parameters affecting on the sensitivity, such as sample pH, sample flow rate, eluent concentration, and eluent flow rate, were carefully examined. Alkali and alkaline earth metal ions commonly existing in river water and seawater did not affect the analysis of metals. Under the optimum conditions, the method allowed the determination of metal ions with detection limits of 0.08 ng mL(-1) (Ag), 0.9 ng mL(-1) (Bi), 0.07 ng mL(-1) (Cu), 0.9 ng mL(-1) (Ga), 0.9 ng mL(-1) (In), 0.08 ng mL(-1) (Mo), 0.09 ng mL(-1) (Ni), 0.9 ng mL(-1) (U), and 0.08 ng mL(-1) (V). By using 5 mL of sample solution, the enrichment factor and collection efficiency were 8-12 fold and 96-102%, respectively, whereas the sample throughput was 7 samples/hour. The method was validated by determining metal ions in certified reference material of river water (SLRS-4) and nearshore seawater (CASS-4), and its applicability was further demonstrated to river water and seawater samples.</p

The Effect of Chrysin Nanoparticles in Preventing the Growth of Mcf-7 Cancer Cells

BACKGROUND AND OBJECTIVE: Chrysin is a natural and biologically active compound extracted from plants, honey and propolis. Since chrysin has pharmacological activities such as antioxidant, anti-inflammatory and anti-cancer properties, this study was conducted to compare the effect of chrysin and its nanoparticle on breast cancer cells (Michigan Cancer Foundation-7). METHODS: In this study, chrysin nanoparticles were prepared using chitosan, and then the prepared nanoparticles were dissolved in water, and the cytotoxic effects of 20, 40 and 80 &#956;M chrysin and chrysin dissolved in dimethyl sulfoxide (at the same concentrations) on MCF7 cells were investigated. Cell viability was measured using MTT assay after 24, 48 and 72 hours, and was compared with viability of the control samples. FINDINGS: The results of this study showed that chrysin and chrysin nanoparticles prevented the growth and proliferation of MCF7 cell line. These effects depend on the concentration of chrysin and its nanoparticles, and it has been shown that the effect of chrysin nanoparticle on cells at a concentration of 40 &#956;M in 72 hours is significant with p&#60;0.001 while it is significant with p&#60;0.01 at the same concentration in 24 and 48 hours. The IC50 value of chrysin nanoparticle was approximately 40 &#956;M. CONCLUSION: The results of the study showed that the chrysin nanoparticle exhibits anti-proliferative activity in breast cancer cells in the laboratory and its effect is greater than that of chrysin

Clinical efficacy of convalescent plasma for treatment of COVID-19 infections: Results of a multicenter clinical study

Since Dec. 2019 the new coronavirus (SARS-CoV-2) has infected millions and claimed life of several hundred thousand worldwide. However, so far no approved vaccine or drug therapy is available for treatment of virus infection. Convalescent plasma has been considered a potential modality for COVID-19 infection. One hundred eighty-nine COVID-19 positive patients including 115 patients in plasma therapy group and 74 patients in control group, registered in the hospitals with confirmed COVID-19 infection, entered this multi-center clinical study. Comparison of outcomes including all-cause mortality, total hospitalization days and patients� need for intubation between the two patient groups shows that total of 98 (98.2 ) of patients who received convalescent plasma were discharged from hospital which is substantially higher compared to 56 (78.7 ) patients in control group. Length of hospitalization days was significantly lower (9.54 days) in convalescent plasma group compared with that of control group (12.88 days). Only 8 patients (7) in convalescent plasma group required intubation while that was 20 in control group. This clinical study provides strong evidence to support the efficacy of convalescent plasma therapy in COVID-19 patients and recommends this treatment for management of these patients. Clinical efficacy, immediate availability and potential cost effectiveness could be considered as main advantages of convalescent plasma therapy. © 2020 Elsevier Lt

Comparison of the performance of bromophenol blue and bromocresol green Sensors in determining the microbial spoilage of (Clupeonella cultriventris caspia) stored in the refrigerator

In this study, a sensor based on chitosan biofilm with bromophenol blue and bromocresol green sensors based on filter paper were used to determine the bacterial quality of common Kilka fish mince in refrigerated temperature. The total viable bacterial count (TVCs) on day zero was 3.473 log CFU / gr, which at the end of the storage period was changed to 6.497 log CFU / gr (p <0.05). The psychrotrophic bacterial counts (PTCs) at the beginning storage time was a 1.473 log CFU / gr and increased during the refrigerated storage time and achieved to 7.516 log CFU / gr (p <0.05). Total volatile basic nitrogen (TVB-N) at the beginning of the storage period was 7.01mg N/100g, which increased to 44.348 mg N/100g at the end of the storage (p <0.05). The pH during storage time changed from 6.105 to 6.827 (p <0.05). The correlation among microbial, chemical and color change values (ΔE) was different, and the highest correlation was observed in bromophenol blue indicator, which correlates with TVCs, The PTCs, TVB-N and pH were 0.941, 0.989, 0.912 and 0.779, respectively (p <0.05). Based on the results of this study, it was found which bacterial and chemical changes spoilage in the minced fish package was simultaneous with the sensors color change and they show a quality decrease as form color change.Publishe

Application of response surface methodology for optimization of trace amount of diazinon preconcentration in natural waters and biological samples by carbon mesoporous CMK-3

Preconcentration of trace amounts of diazinon by carbon mesoporous CMK-3 in water and biological samples and measurement by high-performance liquid chromatography were investigated. CMK-3 was prepared using hexagonal SBA-15 as the template. The synthesized materials were characterized by X-Ray diffraction (XRD), Fourier transform infrared spectroscopy, Brunaur–Emmet–Teller, transmission electron microscopy and Boehm titration method. The preconcentration procedure was optimized using a multivariate optimization approach following a two-stage process. The effect of analytical parameters including the amount of the CMK-3 as an adsorbent, pH, type and volume of eluent and flow rate of eluent and sample were studied by a screening project, then the effective parameters were optimized by response surface methodology based on central composite design. The average extraction efficiency of diazinon under optimal conditions (CMK-3 dosage = 25 mg, sample flow rate = 2.5 mL min−1, eluent flow rate = 1.25 mL min−1, volume of methanol as an eluent =3.5 mL and initial pH = 6) was 97.11, which agrees well with the predicted response value (97.93). The linearity of the method was in the range of 0.5–100 μg L−1 with a correlation coefficient of 0.997. Enrichment factor, limit of detection and limit of quantification were 285.7, 0.09 and 0.23 μg L−1, respectively. The relative standard deviation (RSD) under optimum conditions was 2.21 (n = 5). The proposed method was applied to determine diazinon in real water and biological samples. Recovery of diazinon from real samples was between 95.80 and 104.94 with an RSD of 0.19–4.65. Thus, this method is suitable for the preconcentration and determination of diazinon in real water and biological samples. Copyright © 2016 John Wiley & Sons, Ltd