Abstract
Fluorescent indicators represent powerful tools for studying trace metal homeostasis and signaling events within live cells and tissues. Because trace metal ion concentrations are buffered at very low levels, fluorescent indicators must engage in competitive exchange equilibria with metalloproteins and other endogenous ligands. A meaningful interpretation of the fluorescence response requires therefore a detailed knowledge of the indicator properties and the underlying metal exchange equilibria. In this context, the rigorous characterization of the metal ion binding properties of the fluorescence indicator is of critical importance. After reviewing basic concepts of solution chemistry, this chapter offers an overview of various approaches that can be utilized for the determination of metal stability constants. Special consideration is given to common challenges encountered in the measurement of stability constants as well as to potential artifacts when employing fluorescence indicators within the complex chemical environment of live cells and tissues.
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Financial support from the National Institutes of Health under the award number R01GM067169 is gratefully acknowledged.
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Fahrni, C.J., Bourassa, D., Dikdan, R. (2017). Probing Biological Trace Metals with Fluorescent Indicators. In: White, A. (eds) Metals in the Brain. Neuromethods, vol 124. Humana Press, New York, NY. https://doi.org/10.1007/978-1-4939-6918-0_5
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DOI: https://doi.org/10.1007/978-1-4939-6918-0_5
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