I am trying to covalently attach the RGD peptide sequence to PNIPAM-co-AAc microgels already coated on different substrates (Si, Glass and Polyurethane). I am going to use the common carboxylic acid group (of AAc) activation by EDC and NHS. In this particular case, what would be the best procedure to follow? Should I buy a protected RGD sequence or free RGD is would also be okay? What would be the best characterisation technique to ensure the covalent attachment? ATR-FTIR?
Thank you.