Does AMA or methylamine cause any degradation to fluorescein or fluorescein-type dyes such as FAM or FITC?
RESPONSE:Response: While AMA (Ammonium hydroxide/40% Methylamine 1:1 v/v) is considered compatible with fluorescein, the use of methylamine when deprotecting a Fluorescein-labeled oligo does lead to a small amount of degradation, which is characterized by a the appearance of a late-eluting peak by RP HPLC that shows no visible fluorescein absorbance. With standard deprotection conditions (AMA 10 minutes at 65 C) the amount of degradation is approximately 5%. The impurity is not detected with AMA at RT for 2 hours.
