I used RNA DNA-STAT-60 for purification. The ratio 260/230 is very low. What can I do to improve this ratio? Some co-workers have the same problem. Why is that so and what can we do?
A low 260:230 ratio is indicative of an organic/solvent contamination. I am unfamiliar with the kit you mention. But I would assume it uses a phenol extraction maybe in the presence of guanidinium. If it does not include a chloroform back extraction you could add one. Also be especially careful when you separate your aqueous and organic layers. It is better to leave a bit of sample behind rather than caring over the organic.