i juz finished extract my RNA ...

but the problem is when im check the quality of my RNA, it shows that there are lot contamination of polysaccharides(A260/230 = below 1.0)..

the A260/280 is ok, i think...around 1.7-1.9...

 

actually i want to construct cDNA library..

so, how can i get a good quality RNA to synthesize cDNA???

my fren juz tell me that i can purify my RNA before synthesize cDNA..

is it right?????

 

and 1 more thing, if my RNA not so good , what happen if i continue to synthesize cDNA????

A260/230 does not necessarily mean polysaccharide contamination. Other contaminants absorbing at 230 include for instance guanidine thiocyanate and phenol. Also insufficient resuspension of RNA has an effect on this value.

 

For a simple cDNA it might be not that much of an issue, contamination might effect enzyme activity and are therefore really detrimental for quantitative assays (e.g. QPCR, Microarrays). Otherwise a normal cleanup is recommended. Either use columns or precipitate the RNA and wash with ethanol.

If you're sure the contamination is from polysaccharides I wouldn't worry much about it. I'd be amazed if some simple sugar chains interfered with what you're trying to do.

 

But if you're still concerned take charonY's advice and percipitate it.