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Updated: Jun 28, 2026
13:26
Determination of Protein-ligand Interactions Using Differential Scanning Fluorimetry
Published on: September 13, 2014
Microcomputer application of non-linear regression analysis to metal-ligand equilibria
P D Taylor1, I E Morrison, R C Hider
1Department of Chemistry and Biological Chemistry, University of Essex, Wivenhoe Park, Colchester, England.
Talanta
|July 1, 1988
Summary
A new PC-compatible program optimizes chemical analysis parameters using non-linear least-squares regression. It enhances the accuracy of determining stability constants and pK(a) values for complex chemical systems.
Area of Science:
- Computational Chemistry
- Analytical Chemistry
- Chemical Modeling
Background:
- Accurate determination of chemical parameters like stability constants and pK(a) values is crucial for understanding complex chemical systems.
- Existing computational methods may be limited by hardware or algorithmic constraints.
Purpose of the Study:
- To describe a versatile non-linear least-squares regression program for PC-compatible microcomputers.
- To enable efficient optimization of parameters for multi-component titrations and complex chemical equilibria.
Main Methods:
- Development of a GWBASIC program, compiled for Intel 8087 numeric processor.
- Implementation of the Gauss-Newton-Marquardt algorithm for parameter optimization.
- Simulation of multi-component potentiometric and spectrophotometric titrations.
- Utilizing both analytical and numerical partial derivatives for optimization.
- Incorporation of a "global analysis" feature for comprehensive parameter evaluation.
Main Results:
- The program successfully simulates and optimizes parameters for potentiometric and spectrophotometric titrations.
- Demonstrated application in determining pK(a) values and stability constants for a hydroxypyridinone ligand and its Fe(III) complexes.
- Visual display of experimental data, best fit curves, and speciation enhances data interpretation.
Conclusions:
- The developed program provides a powerful and accessible tool for chemical data analysis on microcomputers.
- It facilitates accurate determination of key chemical parameters, advancing research in coordination chemistry and chemical equilibrium studies.
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