RNA extraction - (Nov/27/2007 )
i am extracting the RNA from soy seeds and leaves, using trizol or phenol;cholorophorm methods. After getting the RNA pellet ,i used to dissolve it in water. Many times i am getting cloudy solution and sometimes viscosity. With spec reading the 260/280 around 1.55-1.75 and 260/230 is 1.95-2.7. are the cloudy and viscosity solutions normal. Is that RNA pure enough for microarray studies?
Your OD 260/280 suggests that there is still proteins/DNA present in your sample (OD260/280 >1.9 for RNA is ok).
What is the concentration of the "RNA", High concentrated DNA/RNA gets viscose.
When you collect the waterphase after trizol treatment make sure you do not touch the interphase and organic phase.
What you can do now is treat your solution with prot K and use an silica based column like Rneasy (Qiagen) to purify you sample,
thanks for your comments. the concentration of the RNA around 3000-6000 ug/ml, which i think high. am i right.
to get the waterphase i am using the Phase Lock Gel-Heavy, that elminate any interphase contamination.
i will try prot K step. is it proK and incubate samples for 30 mins at 60-65.