In solid-phase peptide synthesis, the resin is the polymeric support to which the growing peptide is attached. The linker is the chemical structure connecting the substrate to the resin and helps determine how the final peptide will be released.
The resin is the polymer backbone used as the solid support during synthesis. Different resins behave differently depending on the solvent system.
The linker joins the peptide precursor to the resin and influences the final functional group exposed after cleavage.
Different resins and linkers are selected depending on solvent compatibility, cleavage conditions, and the desired final peptide format.