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Fluorescent IEF Markers

IEF (Isoelectric Focusing) is a powerful analytical tool for the separation of ampholytes, mainly proteins. In order to ensure the high performance of analysis, standards of pI (pI markers) are needed. In addition to classical protein based standards, low molecular compounds were developed and successfully examined in capillary IEF and IEF-gel electrophoresis. An advantage for IEF-gel electrophoresis with fluorescent IEF markers is the possibility to directly observe the formation of the gradient.

Fluorescent IEF markers can also be detected by UV absorption at 280 nm (20 °C). The maximum absorbances of the individual markers are between 308 and 350 nm. For fluorescence detection an excitation wavelength of 310 nm (individual excitation maxima, 310 to 360 nm) is suggested; the emission maxima of the individual markers lies between 412 and 440 nm.