Table of Contents Author Guidelines Submit a Manuscript
Journal of Analytical Methods in Chemistry
Volume 2012 (2012), Article ID 379724, 6 pages
http://dx.doi.org/10.1155/2012/379724
Research Article

Simple Modification of Karl-Fischer Titration Method for Determination of Water Content in Colored Samples

Faculty of Pharmacy, University of Ljubljana, Aškerčeva cesta 7, 1000 Ljubljana, Slovenia

Received 30 November 2011; Accepted 6 March 2012

Academic Editor: Alberto N. Araújo

Copyright © 2012 Eva Tavčar et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The most commonly used technique for water content determination is Karl-Fischer titration with electrometric detection, requiring specialized equipment. When appropriate equipment is not available, the method can be performed through visual detection of a titration endpoint, which does not enable an analysis of colored samples. Here, we developed a method with spectrophotometric detection of a titration endpoint, appropriate for moisture determination of colored samples. The reaction takes place in a sealed 4 ml cuvette. Detection is performed at 520 nm. Titration endpoint is determined from the graph of absorbance plotted against titration volume. The method has appropriate reproducibility ( R S D = 4 . 3 % ), accuracy, and linearity ( 𝑅 2 = 0 . 9 9 7 ).