we can mainly loading glial cell sigh fluo4am. we wonder if there is any tip to make fluo4am loaded mainly into neuron cells. or if there is any other proper Ca2+ dye for neurons.
Apparently Fluo-4-AM preferentially gets into astrocytes when loading it on organotypic brain slices. Here's a very good post about it . A researcher there, recommended Oregeon-Green BAPTA https://www.researchgate.net/post/What_is_the_best_protocol_for_loading_Fluo-4_AM_in_hippocampal_slices
If you coupled your loading protocol with the recommended pluronic acid you might have a better shot to improve your loading. I don't like to think in "astrocyte" or "neuron" specific dyes, but more about the type of question you are trying to answer. Do you care more about [Ca2+]i or more about network dynamics? There are pros and cons of each of these dyes for those two types of questions/analysis.
Also this looks like a very helpful protocol Article Calcium Imaging of AM Dyes Following Prolonged Incubation in...