Can I dissolve PNA oligomers in 0.1% trifluoroacetic acid in order to increase solubility?
Acidic conditions do facilitate the dissolving of PNA oligomers. PNAs supplied by Applied Biosystems are purified by reverse phase HPLC in the presence of trifluoroacetic acid, therefore, dissolving the lyophillisate in water results in a solution with a pH < 3. Addition of extra trifluoroacetic acid should not be necessary and is not recommended because performance of reverse transcription can be affected (potentially resulting in low yield and shorter cDNA fragments).