I have been having problem with the RNaseA lately (last two wks). I
prepare the 10mg/mL solution in 0.01M Tris,Cl, pH8, 0.015M NaCl and boil
for 15 min. After letting it cool to RT I spin for 10 min (15k) and collect
the sup which I subsequently pass through a 0.2u filter and store at -20 C.
This is the way I have done it always (for the last 15 yrs) and have never
had my plasmid preps disappear the way they are doing now. It is the same
Sigma bottle that I prepared my last stock from. What is the possible
answer? Can anybody suggest a solution and/or a foolproof preparation (no,
we can not buy the DNase-free stuff).
Dr. Hiranya Sankar Roychowdhury
Plant Genetic Engineering Lab.
New Mexico State University
Las Cruces, NM 88003
Ph. (505) 646-5785
hroychow at nmsu.edu