What is the stability of deprotected oligonucleotides in NH4OH?
RESPONSE:Q. Is it OK to store deprotected oligos in NH4OH untill ready to use. A. Its OK to store the oligo in NH4OH at -20°C especially if the DMT group has been retained for further purification. For DMT-OFF oligos its better If they are lyophilized and stored at -20°C. This is the most stable form for the oligo. Q. What is the best way to store a crude oligo if no further purification is to be used. A. For crude DMT off oligos it is better to do a quick EtOH ppt. before use. This will remove protecting groups and any other salts which might be present. After EtOH ppt. the oligo can again either be stored lyoplilized at -20°C or you can determine its concentration and store in solution at -20°C. A good buffer for storage is 10 mM Tris containing 1 mM EDTA to chelate any divalent cations which could activate any DNase which might be present. FAQs QUESTION: You say that the sulfurizing reagent, 40-4036, is stable for 1 month in solution “under ideal conditions”. What are ideal conditio
