Combination of dezincification carbon anhydrase with dansylamide for zinc biosensing

Abstract

This work demonstrated quantitatively that DSA (dansylamide) and apo CA (dezincified carbon anhydrase) interacted with each other in the presence of Zn²⁺ (zinc ion). The fluorescence emission of DSA in the presence of Zn²⁺ and the intensity of fluorescence, which was proportional to the concentration of Zn²⁺, could be used in the measurement of Zn²⁺ concentration. Considering that Zn²⁺ was the active center of enzymes like CA (carbon anhydrase), two dezincification reagents were compared to ensure the validity of our method. A certain range concentration of Zn²⁺ could be measured by the reaction product of apo CA, DSA and Zn²⁺, where the measurement limitation was about 60 nmol/L. Interaction of CA with DSA was also studied with infrared spectrometry.

Keywords

fluorescence / dezincification / carbon anhydrase / dansylamide / zinc

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