Abstract
Chemical speciation of binary complexes of Co(II), Ni(II), Cu(II) and Zn(II) with L-aspartic acid was investigated pH-metrically in acetonitrile- and ethylene glycol-water mixtures. The stability constants were calculated using the computer program MINIQUAD75. The best-fit chemical models were selected based on statistical parameters and residual analysis. The models for the binary species contained ML2H2, ML2H and ML2 for Co(II) and Zn(II), ML, ML2H2 and ML2 for Ni(II) and Cu(II) in acetonitrile- and ethylene glycol-water mixtures. The trend in variation of stability constants with change in the dielectric constant of the medium was explained on the basis of electrostatic and non-electrostatic forces. Distribution of the species with pH at different variations (0.0-60.0% v/v) in acetonitrile- and ethylene glycol-water mixtures was also presented. KEY WORDS: Complex equilibria, L-Aspartic acid, Acetonitrile, Ethylene glycol, MINIQUAD75 Bull. Chem. Soc. Ethiop. 2012, 26(2), 239-247.DOI: http://dx.doi.org/10.4314/bcse.v26i2.7
Highlights
A number of studies have been reported on chemical speciation of α-amino acids in different media in recent times [1,2,3]
L-aspartic acid is a non-essential amino acid found in abundance in plant proteins
The small values of Ucorr indicate that the experimental data can be represented by the model
Summary
A number of studies have been reported on chemical speciation of α-amino acids in different media in recent times [1,2,3]. Chemical speciation of a molecule is governed by its structure and solvent effects [4, 5]. L-aspartic acid is a non-essential amino acid found in abundance in plant proteins. It plays an important role in maintaining the solubility and ionic character of proteins [6]. It assists the liver in removing excess ammonia and other toxins from the blood stream. It is very important in the functioning of RNA and DNA, in immunoglobulin and antibody synthesis. Asp is popular as a drug for chronic fatigue as it plays crucial role in generating cellular energy, moves the coenzyme nicotinamide adenine dinucleotide molecules from the main body of the cell to its mitochondria, where it is used to generate adenosine triphosphate (ATP) [7]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
