“…Other dyes, such as fluo‐3 and fluo‐4, do not have this shift in spectrum when binding Ca 2+ , but can be used for the detection of intracellular Ca 2+ concentrations because their fluorescence intensity increases in the Ca 2+ bound state. Ca 2+ mobilization is then estimated via the increase in fluorescence intensity after excitation at a single wavelength (Arunotayanun et al, 2013; Blough et al, 2014; Brandt et al, 2018; Cussac et al, 2008; Elmore et al, 2018; Flanagan et al, 2021; Halberstadt et al, 2019, 2020; Jensen et al, 2017; Jerman et al, 2001; Klein et al, 2021; Kolaczynska et al, 2019; Leth‐Petersen et al, 2016; Luethi et al, 2018, 2019; Marcher‐Rorsted et al, 2020; Minta et al, 1989; Nichols et al, 2015; Ray, 2010; Rickli et al, 2015; Rickli, Luethi, et al, 2015; Sullivan et al, 1999).…”