Alkali metals biological systems containing

Probes based on macrocyclic amines include dansylamidoethylcyclen, which can detect zinc at sub-nanomolar concentrations and probes containing xanthene as the chromophore with an ideal wavelength range for intracellular studies.953,962 It is also important that the sensors can differentiate between the alkali metals, which are present at higher concentrations, and zinc. 2, 7-dichlorofluorescein-based sensors have been used in biological systems and reveal concentrations up to ca. 0.3 mM in hippocampal nerve synaptic vesicles.963... 

Macrolides of this group contain two or more lactones in a large system. An antibiotic of this group has a hydrophilic hole capable of binding an alkali metal cation and thus of transporting ion in biological systems. Nonactin 4 (Figure 6.2) and bafilomydn A1 [24] represent this class. 

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