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A computer-controlled potentiometric/spectrophotometric titrator
1Merck Sharp & Dohme Research Laboratories PO Box 2000 Rahway New Jersey 07065 USA.
The Journal of Automatic Chemistry
|January 1, 1988
Summary
A new computer-controlled potentiometric titrator interfaced with a spectrophotometer offers precise chemical analysis. This system demonstrates reliable performance for determining titres and acid dissociation constants (pKa).
Area of Science:
- Analytical Chemistry
- Instrumental Analysis
Background:
- Potentiometric and spectrophotometric titrations are essential analytical techniques.
- Integrating these methods can enhance analytical capabilities and efficiency.
Purpose of the Study:
- To describe a laboratory computer-controlled potentiometric titrator interfaced with a diode array spectrophotometer.
- To evaluate the system's performance and data handling capabilities.
Main Methods:
- Utilized widely available commercial components for system construction.
- Developed software for interconnection, data format, and system control.
- Performed replicate potentiometric titrations of glycines and spectrophotometric titrations of bromophenol blue.
Main Results:
- Potentiometric titrations of glycines yielded a relative standard deviation in titre of 1.035% and in pH of 0.745%.
- Spectrophotometric titrations of bromophenol blue determined pKa = 3.898 ± 0.075 (1.9% rsd).
Conclusions:
- The described system provides a reliable and accurate platform for combined potentiometric and spectrophotometric titrations.
- The developed software facilitates effective data presentation and manipulation for analytical applications.
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