I am using FFPE tumor samples that are used for laser microdissection (Leica). Prior to laser microdissection, the tissue is deparaffinized and stained with hemotoxylin. LMD samples are stored in Buffer RLT at -80C until RNA extraction.

RNA yield varies between:

2 - 20 ng/ul total RNA

260/280 numbers range from 1.45 - 2.2,

260/230 numbers range are less than 0.40.

I follow the Qiagen Micro Kit protocol as stated and have tried including extra Buffer RPE steps but did not achieve better results.

Any suggestions on how to improve 260/230 numbers? Or any suggestions on another kit to use for my samples?