ceridwan

hello everybody,
i have to isolate total rna of pancreatic islets for performing microarrays. my first trials with trizol (100 islets in 1ml) or nucleospin II RNA (100 islets) resulted in poor ratios (A260/A280 and A260/A230). for rna isolated with trizol i used the nucleospin II as clean up. thus i do not have a lot of experience with isolating rna i am asking myself, if one can use too much trizol reagent for sample homogenization, how i can improve my rna ratios and if there is something special to take in account isolating rna from murine pancreatic islets (isolated by common collagenase perifusion of the entire pancreas).
i would really appreciate your help,
have a nice evening,
ceridwan