18 research outputs found
Voltammetric Determination of Homocysteine Using Multiwall Carbon Nanotube Paste Electrode in the Presence of Chlorpromazine as a Mediator
We propose chlorpromazine (CHP) as a new mediator for the rapid, sensitive, and highly selective voltammetric determination of homocysteine (Hcy) using multiwall carbon nanotube paste electrode (MWCNTPE). The experimental results showed that the carbon nanotube paste electrode has a highly electrocatalytic activity for the oxidation of Hcy in the presence of CHP as a mediator. Cyclic voltammetry, double potential step chronoamperometry, and square wave voltammetry (SWV) are used to investigate the suitability of CHP at the surface of MWCNTPE as a mediator for the electrocatalytic oxidation of Hcy in aqueous solutions. The kinetic parameters of the system, including electron transfer coefficient, and catalytic rate constant were also determined using the electrochemical approaches. In addition, SWV was used for quantitative analysis. SWV showed wide linear dynamic range (0.1ā210.0āĪ¼M Hcy) with a detection limit of 0.08āĪ¼M Hcy. Finally, this method was also examined as a selective, simple, and precise electrochemical sensor for the determination of Hcy in real samples
Determination the optimal conditions of chemical modification on Poplar wood with Glutaraldehyde and physical properties of products
This research was conducted to determine the optimal conditions for chemical modification of poplar wood with glutaraldehyde and its effect on the physical properties of products. Test samples were prepared according to the standard ASTM-D1037 and impregnated in the laboratory cylinders with Glutaraldehyde at a concentration of 10% by using vacuum-pressure method. Modification reaction was done in two procedure. Heating first in the laboratory cylinder (Hydrothermal) for 4 hour and second in oven for 4 level 4,12,24,48 and 48hours. Weight percent gain of modified by hydrothermal and oven method was measured 2.10, 9.26, 10.02, 11.40 and 14.15% respectively. Chemical modification with glutaraldehyde by hydroxyl group's substitution, reduced the uptake of water and swelling of poplar wood. So that at the end of soaking in water the heating in the oven for 48 hours with minimum water absorption and dimensional changes in the 57.32 and 12.08 respectively, and highest bulking, ASE and ASEā² in 8.31,67 and 35.51% respectively was selected as the optimal level. This improvement compared to other modification levels demonstrates the forming of permanent Cross-linking of acetal that increased by Prolongation of the heating time
Methyldopa electrochemical sensor based on a glassy carbon electrode modified with Cu/TiO2 nanocomposite
A Cu/TiO2 nanocomposite modified glassy carbon electrode (Cu/ /TiO2/GCE) was fabricated to detect methyldopa by cyclic voltammetry (CV) and different pulse voltammetry (DPV) methods. Compared with bare GCE, the Cu/TiO2/GCE exhibited excellent electrochemical activity for the oxidation of methyldopa. Using DPV technique, the calibration curves for methyldopa were found linear in the concentration range of 0.5ā800.0 Ī¼M and the detection limit (S/N = 3) was calculated to be 0.23 Ī¼M. Additionally, the prepared electrochemical sensor of Cu/TiO2/GCE demonstrated a practical feasibility in methyldopa tablets and in urine samples analysis
Cytotoxicity Effect of Cold Atmospheric Plasma on Melanoma (B16-F10), Breast (MCF-7) and Lung (A549) Cancer Cell Lines Compared with Normal Cells
Background and purpose: Cancer is one of the major health challenges in the world. The efficacy of current treatments is low but their side effects are high. Cold atmospheric plasma (CAP) is a new modality for cancer treatment. This study aimed to compare the cytotoxicity effect of CAP on the cell line models of common cancers and normal cells.
Materials and methods: In this experimental study, argon based CAP was used to treat mouse melanoma (B16-F10), human breast cancer (MCF-7), human lung cancer (A549) cell lines, and compared with normal mouse fibroblast cells (L929), and human immortalized normal respiratory epithelial cell (Beas). We cultivated 4 groups in each cancer and normal cell lines: untreated cells; CAP exposed cellsĀ for 20 seconds, 30 seconds, and 40 seconds.The morphological alterations and proliferation rate of the cells were evaluated after 24 and 48 hours.
Results: The viability of CAP-treated cancer cells significantly decreased compared to that of the untreated cells. The viability of A549 and MCF-7 cell lines decreased to 33.9% and 49.5%, 24 hours after CAP therapy for 30 seconds. In addition, 40 seconds exposure to CAP reduced viability of B16-F10 melanoma cells to 37.9%. Whereas the CAP had no detrimental cytotoxic effect on normal L929 cells. The maintenance effect of CAP had a time dependent pattern and its cytotoxicity effect increased from 24 to 48 hour incubation.
Conclusion: This study showed that the effect of CAP on cancer cells is a selective effect that is largely dependent on the radiation dose and duration of exposure of cells to compounds produced by CAP. We can use CAP in treatment of cancer because of its cytotoxicity and selectivity on cancer cells
Seminal plasma total antioxidant capacity and vitamin- C levels in asthenozoospermia: a case- control study
"n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Defective sperm function is now recognized as one of the most important causes of male infertility. Seminal plasma possesses a rich source of different enzymatic and non-enzymatic antioxidants such as vitamin C (ascorbic acid) that protect spermatozoa against oxidative stress as one of the mediators of infertility causing sperm dysfunction and low sperm quality. The aim of this study was investigation of seminal total antioxidant capacity and determination of vitamin C effects on sperm motility. "n"nMethods: We designed a case-control study with a total subject of 62 males. Sperm parameters were analyzed according to World Health Organization guidelines (WHO, 1999). Total antioxidant capacity and vitamin C level of seminal plasma were measured in the 32 normozoospermic as the control group and 32 asthenospermic men as the case group using FRAP (Ferric Reducing of Antioxidants Powers) and RP-HPLC (Reverse Phase High Performance Liquid Chromatography) methods, respectively. "n"nResults: Our results indicated that total antioxidant capacity levels in the seminal plasma of asthenospermic men were significantly lower than healthy men (p=0.002). In addition, we found a positive correlation between reduced total antioxidant capacity levels and low sperm motility. Vitamin C levels of seminal plasma in asthenospermic men were statistically lower than control men (p=0.01)."n"nConclusions: It is suggested that asthenospermia could be related to an antioxidant deficiency or it's reduction
Combination effect of cold atmospheric plasma with green synthesized zero-valent iron nanoparticles in the treatment of melanoma cancer model.
Green synthesized zero-valent iron nanoparticles (nZVI) have high potential in cancer therapy. Cold atmospheric plasma (CAP) is also an emerging biomedical technique that has great potential to cure cancer. Therefore, the combined effect of CAP and nZVI might be promising in treatment of cancer. In this study, we evaluated the combined effect of CAP and nZVI on the metabolic activity of the surviving cells and induction of apoptosis in malignant melanoma in comparison with normal cells. Therefore, the effect of various time exposure of CAP radiation, different doses of nZVI, and the combined effect of CAP and nZVI were evaluated on the viability of malignant melanoma cells (B16-F10) and normal fibroblast cells (L929) at 24 h after treatment using MTT assay. Then, the effect of appropriate doses of each treatment on apoptosis was evaluated by fluorescence microscopy and flow cytometry with Annexin/PI staining. In addition, the expression of BAX, BCL2 and Caspase 3 (CASP3) was also assayed. The results showed although the combined effect of CAP and nZVI significantly showed cytotoxic effects and apoptotic activity on cancer cells, this treatment had no more effective compared to CAP or nZVI alone. In addition, evaluation of gene expression showed that combination therapy didn't improve expression of apoptotic genes in comparison with CAP or nZVI. In conclusion, combined treatment of CAP and nZVI does not seem to be able to improve the effect of monotherapy of CAP or nZVI. It may be due to the resistance of cancer cells to high ROS uptake or the accumulation of saturated ROS in cells, which prevents the intensification of apoptosis