A total survey upon L-histidine complexes of some toxic metal ions in DMSO-water mixtures
Publish place: National Conference on Nanotechnology and Green Chemistry
Publish Year: 1391
نوع سند: مقاله کنفرانسی
زبان: English
View: 864
This Paper With 6 Page And PDF Format Ready To Download
- Certificate
- من نویسنده این مقاله هستم
استخراج به نرم افزارهای پژوهشی:
شناسه ملی سند علمی:
IAUET01_060
تاریخ نمایه سازی: 9 تیر 1392
Abstract:
In This letter, A special study has been done upon some toxic metal ion complexes. these kind of researches are useful for understanding the role played by the active site cavities in biological molecules and the bonding behavior of protein residues with the metal ions. The species refined and their relative concentrations under the experimental conditions represent the possible forms of aminoacids in biofluids. In this letter, An Equilibrium study upon the complex formation of L-histidine with As(III), Cd(II), and Hg(II) has been investigated pH metrically in DMSO-water mixtures (0–60% v/v) at 303 K and 0.16 mol L(−1) ionic strength. The models containing different numbers of species were refined by using the computer program MINIQUAD75. The species distribution and the plausible equilibria for the formation of the species are also presented. The computer program SCPHD was used to calculate the correction factor. The following conclusions have been drawn from the modeling studies of the L-Histidine complexes of As(III), Cd(II) and Hg(II) in DMSO-water mixture:(1) L-Histidine forms both protonated and unprotonated complexes under pH range 2.0–9.0. The species detected for the toxic metals As(III) and Cd(II) are:ML(2) H(4) , ML(2) H(3) , ML(2) H(2) , ML(2) H, and ML(2) . ML(2) H(4) , ML(2) H(3) , ML(2) , and ML species are detected the case of Hg(II).(2) The linear variation of stability constants as a function of 1/D of the medium indicates the dominance of electrostatic forces over nonelectrostatic forces. The linear increasing trend with DMSO content supports the dominance of the structure forming nature of DMSO over its complexing ability.(3) The order of ingredients in affecting the magnitudes of stability constants due to incorporation of errors in their concentrations is alkali > acid > metal> ligand > volume > log F.(4) Some species are stabilized due to electrostatic interactions and some are destabilized due to the decreased dielectric constant.
Keywords:
Authors
Kourosh Motevalli
Department of Applied Chemistry, Islamic Azad University, South Tehran Branch, Tehran, Iran
Zahra Yaghoubi
Faculty of Industrial Engineering, Islamic Azad University, South Tehran Branch, Tehran, Iran
مراجع و منابع این Paper:
لیست زیر مراجع و منابع استفاده شده در این Paper را نمایش می دهد. این مراجع به صورت کاملا ماشینی و بر اساس هوش مصنوعی استخراج شده اند و لذا ممکن است دارای اشکالاتی باشند که به مرور زمان دقت استخراج این محتوا افزایش می یابد. مراجعی که مقالات مربوط به آنها در سیویلیکا نمایه شده و پیدا شده اند، به خود Paper لینک شده اند :