when i faced such a problem i i repeated ethanol wash step. i worked for me. not sure though. but m pretty sure that treating with more RNase wont help resolving this issue.

Hi Alicia,

As Sansrity said, increase the number of washes with ethanol to get better ratio.

Prasad.

Hi Alicia,

Do the following,

1. use the recommended amount of plant material.

2. Check the color of the flow through of the ethanol wash before eluting the DNA. keep washing until the flow through is colorless.

I think it will help, even though, I've never tried them on DNeasy Plant Mini Kit.

Hi Alicia,

Absorption at 230 nm reflects impurities of e.g. carbohydrates, peptides,

phenols, or aromatic compounds.

The 260/230 should be above 2 for pure samples (around 2.2). Your sample seems to be fine since it has 260/230 ratio 2.3.You can proceed further with your samples.

Ashish

I agree with Ashish. You need proceed to the next steps and evaluate the obtained results. What 260/280 ratio do you have?

1. If you are using NanoDrop for measuring, this is the advice from its technical bulletin [see attachment]:

A high A260/A230 ratio may be the result of: 

• Making a Blank measurement on a dirty pedestal 

• Using an inappropriate solution for the Blank measurement. The blank solution should be the same pH and of a similar ionic strength as the sample solution.   Example: Using water for the Blank measurement for samples dissolved in TE may result in low 260/230 ratios.

2. What blank solution did you use?

Hi,

You may increase the number of washes with ethanol to get better ratio.

Alternatively, you can try CTAB method. Usually, the DNA yield is much better as well as the ratios.

Good luck.

Hi everyone, Thanks for all your advice.

Have you tried to obtain and obtained lower A260/A230 ratio since?