Analytical Application of pH-Gradients in Flow Injection Analysis and Related Techniques

pH gradients in flow systems have proved useful for performing multiple analytical tasks. Although the reproducibility, sampling frequency and degree of automation makes these techniques highly attractive from an analytical point of view, data generated often suffer from poor selectivity. From a historical perspective, following their initial application at the end of the seventies, these methods fell into disuse as a consequence of interference problems. Today, the potentiality of pH-gradients has greatly increased, mainly in combination with mathematical procedures for data analysis addressed at improving the selectivity. This paper describes the existing systems for the generation of pH gradients and provides an overview of applications dealing with the study of pH-dependent processes, quantitative determinations and the calculation of stability constants. The characteristics, advantages and shortcomings of the

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