PEG-NovaTag^TM resins:

allow direct synthesis of peptides with
   C-terminal PEG spacer
lead to improved solubility of peptides and
   biotinylated peptides by introduction of
   PEG spacer
compatible with standard Fmoc peptide
   synthesis protocols

Novabiochem's PEG-based building blocks for solid phase peptide synthesis can be introduced using standard coupling methods, such as PyBOP or TBTU and are compatible with standard TFA cleavage protocols.
Applications in peptide and protein chemistry are numerous:
as flexible spacers to link peptides
to separate peptides from reporter groups such as fluorophores and biotin
to increase peptide solubility both in aqueous and organic solvents
to delay enzymatic digestion in biological systems

For a comprehensive survey on NovaTag^TM resins see:
Letters 1/04

For a summary of Novabiochem PEG reagents see:
Letters 3/06

Letters 1/07