Sorry dr M.Mahdy but i use most of these ways to try to isolate RNA from buffalo sperm cells , but always the results so weak cincentration or nothing, also i try to use fresh, freezing and sperm straws also try to isolate RNA from sample collected on RNA later.
Do you have aspecial protocol already gives good results. Of course you know that these type of work spent alot of money and so i cant overstand all of these chemicals lost.