I need to develop a protocol to fix hemocyte extractions from Drosophila. The samples need to last at least two weeks since immediate analysis is not possible. Also, I will be using LacZ, so Beta-Gal activity must also be decently preserved. I will also be doing GFP analysis--if fluorescence is disrupted, I can use an antibody, but then the GFP antigenicity must also be decently preserved. I know Glutaraldehyde blocks Beta-Gal, but is better for long term fixing than paraformaldehyde. Any glutar:paraform ratio suggestions? Do I need to permeablize the cells?
Thank you so much,
Matt