Description

Bis-dPEG®5, half benzyl half NHS ester, product number QBD-10237, is a short, discrete PEG (dPEG®) modification reagent designed for stepwise reactions with amines. Both ends of the single molecular weight PEG linker terminate with propionic acid groups. One end is functionalized as the N-hydroxysuccinimidyl (NHS) ester, while the other acid end is protected as the benzyl ester. The benzyl ester can be removed using hydrogen with a palladium catalyst.

The dPEG®5 linker increases conjugates’ hydrodynamic volume and hydrophilicity. QBD-10237 is useful for crosslinking amines under controlled conditions, modifying peptides at N-termini or amine-functionalized side chains, and building supramolecular constructs that require flexible, hydrophilic spacers.

Specifications

Documents

References

1. Greg T. Hermanson, Bioconjugate Techniques, 3rd Edition, Elsevier, Waltham, MA 02451, 2013, ISBN 978-0-12-382239-0; See Chapter 18, Discrete PEG Reagents, pp. 787-821, for a full overview of the dPEG® products.

Description

Bis-dPEG®5-acid, product number QBD-10230, is a short, monodisperse, homobifunctional polyethylene glycol (PEG) compound designed for crosslinking amines. Two propionic acid groups terminate either end of a discrete PEG (dPEG®) chain. These two end groups can be coupled directly to amines using a carbodiimide such as EDC. Alternatively, the carboxylate ends can be functionalized as active esters. Reactive groups such as NHS, TFP, PFP, and HOBt are suitable for this purpose. Reaction with various amines follows the activation step.

The hydrophilic dPEG® spacer imparts water solubility and flexibility to molecules to which it is conjugated. Moreover, conjugates containing dPEG® moieties have increased hydrodynamic volume. Also, the non-immunogenic crosslinker reduces or eliminates the antigenicity of the resulting conjugates.

Peptides, proteins, amine-containing biomolecules, and small molecules with primary or secondary amine groups can all be crosslinked with Bis-dPEG®5-acid. It may also be useful for peptide stapling or as a building block for macromolecular constructs.

Specifications

Documents

References

1. Greg T. Hermanson, Bioconjugate Techniques, 3rd Edition, Elsevier, Waltham, MA 02451, 2013, ISBN 978-0-12-382239-0; See Chapter 18, Discrete PEG Reagents, pp. 787-821, for a full overview of the dPEG® products.

Description

Acid-dPEG®5-NHS ester, product number QBD-10109, is an amine-reactive crosslinker that is designed to facilitate intermolecular crosslinking with free amines at each end of the crosslinker through a single molecular weight, discrete polyethylene glycol (dPEG®) backbone. Because one end of the chain terminates in a propionic acid group while the other end terminates as the N-hydroxysuccinimidyl (NHS) ester of propionic acid, this product can effectively overcome the problems typically afflicting homobifunctional crosslinkers. Moreover, the carboxylic acid end can remain unmodified, allowing the carboxylic acid to be used as a charge modifier in supramolecular and bioconjugate construction. Furthermore, the amphiphilic dPEG® backbone imparts water solubility to conjugate molecules.

Specifications

Documents

References

1. Greg T. Hermanson, Bioconjugate Techniques, 3rd Edition, Elsevier, Waltham, MA 02451, 2013, ISBN 978-0-12-382239-0; See Chapter 18, Discrete PEG Reagents, pp. 787-821, for a full overview of the dPEG® products.

Description

Fmoc-N-amido-dPEG®5-acid, product number QBD-10053, is one of a broad line of products designed for use in peptide synthesis. The short (19 atoms), discrete PEG (dPEG®) spacer is functionalized with a propionic acid group on one end and Fmoc-protected amine on the other. The product can be added to the N-terminus of a growing peptide chain or to a primary-amine-functionalized side chain of an amino acid such as lysine. The dPEG®5 spacer imparts water solubility to the peptide to which it is conjugated.

QBD-10053 permits our customers to insert a dPEG® spacer into a peptide chain using familiar Fmoc chemistry using solid phase or solution phase chemistry. The dPEG® compound can be inserted at either end of the peptide chain or in the middle of two amino acid sequences to provide a flexible linker between distinct functional peptides. Additionally, the dPEG® spacer can be used to provide spacing in a synthetic construct where steric hindrance is a problem. The amphiphilic nature of dPEG® products means that the construct gains hydrodynamic volume and water solubility while remaining soluble in organic solvent. The Fmoc protecting group removes easily with a solution of piperidine in N,N-dimethylformamide (DMF).

Specifications

Documents

References

1. Greg T. Hermanson, Bioconjugate Techniques, 3rd Edition, Elsevier, Waltham, MA 02451, 2013, ISBN 978-0-12-382239-0; See Chapter 18, Discrete PEG Reagents, pp. 787-821, for a full overview of the dPEG® products.

2. Design of a modular tetrameric scaffold for the synthesis of membrane-localized D-peptide inhibitors of HIV-1 entry. J. Nicholas Francis, Joseph S Redman, Debra M Eckert, and Michael S. Kay. Bioconjugate Chemistry. 2012, 23 (6), pp 1252-1258. May 1, 2012. DOI: 10.1021/bc300076f.

3. Enhanced Cellular Uptake of Peptide-Targeted Nanoparticles through Increased Peptide Hydrophilicity and Optimized Ethylene Glycol Peptide-Linker Length. Jared F. Stefanick, Jonathan D. Ashley, and Basar Bilgicer. ACS Nano. 2013, 7 (9) pp 8115–8127. August 29, 2013. DOI: 10.1021/nn4033954.