Modification of PNAs for specific uses
PNAs may need to be modified for specific applications. They can be modified either during synthesis or after synthesis. For instance, during synthesis, PNA can be modified either by coupling amino acids during solid phase synthesis or by attachment of compounds, that contain carboxylic group to the exposed N-terminal amine. After synthesis, a PNA can be modified by coupling to an introduced lysine or cysteine. Once synthesized and modified, the identity of a PNA can be confirmed by mass spectrometry.