ZIGIR enables the separation of heterogenous beta cells based on their insulin content and sorting of islets into pure alpha cells and beta cells. In human islets, ZIGIR facilitates the sorting of endocrine cells into highly enriched alpha and beta, revealing an unexpected high zinc(II) activity in the somatostatin granule of some delta cells and uncovering variation in the glucagon content among human alpha cells.
ZIMIR is a fluorescent zinc indicator for monitoring exocytosis of zinc containing granules. Its fluorescence intensity increases about 70-fold upon zinc(II) chelation. ZIMIR is an amphiphilic molecule containing four negative charges and a pair of lipophilic dodecyl chains. When added to cells at micromolar concentration, ZIMIR labels the outer leaflet of the cell membrane rapidly and non-invasively, and reports the local increase in zinc activity immediately adjacent to the plasma membrane at the sites of granule fusion. ZIMIR binds zinc(II) with a dissociation constant of 0.45 µM while maintaining excellent selectivity against calcium(II) (mM) and magnesium(II) (mM).
ZIMIR is provided as a solid in vials containing 0.1 mg or 1 mg.
CP027 is a zinc(II) selective MRI contrast agent that exhibits an extremely high T1 relaxivity in vivo upon zinc(II) complexation and binding to human serum albumin (HSA). Therefore, it represents a powerful sensor for zinc(II) rich tissues, e.g. pancreatic and prostatic tissue. CP027 is provided as a solid.
DPAS is a soluble and hydrophilic zinc chelator derived from dipicolylamine which binds zinc(II) with good selectivity against calcium(II) and magnesium(II). DPAS can be used to chelate residual zinc(II) commonly present in biological salines. In addition, during ZIMIR imaging of zinc granule release, DPAS promotes zinc(II) dissipation from the cell membrane into the bulk soution to facilitate revealing pulsatory releases of zinc granules.DPAS is provided as a solution also containing 50 mM HEPES buffer (pH 7.4).
Intercellular communication through gap junction channels is crucial for maintaining cell homeostasis and synchronizing physiological functions of tissues and organs. NPE-HCCC2/AM is a caged and cell permeable coumarin probe that can be locally photolyzed in one or a subpopulation of coupled cells and the cell–cell dye transfer can be monitored by digital fluorescence microscopy. Post-acquisition analysis can be used to quantify the rate of junction dye transfer using Fick’s equation. This local activation of a molecular fluorescent probe (LAMP) assay can be conveniently carried out in fully intact cells to assess the extent and degree of cell coupling, and is compatible with other fluorophores emitting at different wavelengths to allow multicolor imaging. Moreover, by carrying out multiple photo-activations in a coupled cell pair, the LAMP assay using NPE-HCCC2/AM can be used to track changes in cell coupling strength between coupled cells, hence providing a powerful method for investigating the regulation of junctional coupling by cellular biochemical changes.
