How do you deprotect oligos containing O6-Me-dG and O4-Me-dT?
RESPONSE:1. Cleave the sequence from the synthesis column with ammonium hydroxide using the normal procedure. 2. Dry the ammonium hydroxide solution in a vacuum centrifuge. 3. Meanwhile make up a solution of 10% DBU in anhydrous methanol. DBU (1,8-Diazabicyclo[5.4.0]undec-7-ene) is available from Aldrich (13,900-9) as is anhydrous methanol (32,241-5). Mix 0.5mL DBU with 4.5mL methanol in a clean, dry 5mL septum-capped glass vial. 4. Dissolve the dried oligo pellet in 1mL of 10% DBU solution and transfer it to a clean, dry glass vial. Cap the vial tightly. 5. Place the vial in a dry dark place and leave it for 5 days. Transfer the contents to a micro centrifuge tube and lyophilize to a small volume. 6. Add 1mL of 10mM aqueous sodium hydroxide solution and desalt or purify the oligonucleotide using standard procedures. FAQs QUESTION: What is the best method to deprotected thio-modified oligos (10-1926)? RESPONSE:The trityl group used to protect the thiol is not acid labile and therefore
