I am working on some grape Vitis arizonica leaf extractions and after extraction they look great on nanodrop with 260/280 between 1.72 and 2.05 for all samples and 260/230 between 1.7 and 2.10 for all samples. All concentrations also looked good. Although on the gels there was a blob around or slightly less than 100bp which is RNA contamination. For this I was instructed to do an RNase A treatment (I had already done an rnase treatment during lysis). After doing another rnase A treatment post elution I re-precipitated the DNA using sodium acetate and ethanol to remove rnase (centrifuged @4c), then washed the pellet twice with 70% ethanol. Then I ran a gel and it looked good, high molecular weight gDNA (above 10000 bp) with no RNA blob at the bottom. However, the confusing part is my nanodrop now looks horrible on any sample that I treat with rnase A and re-precipitate. I get 260/280 of 1.4-1.7 and 260/230 under 1.0 for any of these samples. I am not sure what contaminant could be there?

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