The PEC-Linker RC+
The PEC-Linker RC+ generation reflects the latest advancements in catch-and-release methodologies (Figure 1). All three construction blocks are optimized and tailored to allow general applicability as well as reliable and highly efficient purification and modification experience for the user.
Figure 1. Molecular structure of the PEC-LInker RC+.
- Remove the Boc protecting group during the acid treatment for cleavage from the SPPS resin. The activated amino-oxy function serves as the anchor to the activated filter material.
- A Bromo-substituted para azido-benzyl carbamate acts a the cleavable unit and represents the heart of the PEC-Linker RC+. The construction enables a well-balanced stability behavior, depending on the pH of the medium: Reducing the azide to an amine sensitizes the linker to cleavage. However, the fracture does not occur at neutral pH enabling wash out of by-products formed during reduction. Finally, the treatment of the safety-release system with weak acids liberates the peptide through an acid-catalyzed 1,6-elimination.
- The para-nitrophenol represents an ideal leaving group with precisely tuned reactivity and storage stability.
PEC-Linker RC+ in action
The general scheme of PEC purification by catch-and-release consists of six steps shown in Figure 2.
Figure 2. Detailed scheme of the PEC process using the PEC-Linker RC+.
- Couple the PEC-Linker to the target peptide at the end of the solid-phase peptide synthesis (SPPS). Capping after each amino acid coupling cycle to ensures the selective coupling on the target full-length sequence.
- Cleave the peptide from the SPPS resin using respective TFA-cocktails.
- Immobilize through covalent capture ("Catch ") on the activated filter material in an oxime ligation.
- The covalent capture allows the washing out of unbound substances such as truncated sequences and additionally enables you to modify the bound, unprotected peptide selectively.
- Precipitate and dissolve the peptide
- a) The subsequent reduction of the PEC-Linker sensitizes the system for-safety release of the peptide.
b) Liberate the purified peptide via weak acidic induced 1,6-elimination and elution ("Release").
The activated filter material
Aldehyde-modified agarose reflects the state-of-the-art solid-phase equipment for catch-and-release methodologies. We offer an optimized agarose material (Agarose100) with high stability, and a high loading capacity of 100 µmol per mL settled resin in our current kit products.
Figure 3. Microscopy image of the activated agarose filter material.