PEG Conjugated Peptide
PEGylated peptides have high solubility and bioavailability, and can enhance the therapeutic effect of peptides by camouflaging the peptide and fooling the host cell's immune system. BOC Sciences is committed to providing comprehensive peptide PEGylation services to our customers and assisting them in peptide design & development.
PEGylated Peptides
PEGylated peptides are produced by chemically modifying peptide molecules with polyethylene glycol (PEG), in order to alter the properties of the peptide and to improve its stability and drug delivery properties in organisms. Peptides have many potential therapeutic benefits as drug candidate molecules, but there are some limitations. For example, peptides are susceptible to enzymatic degradation in vivo, leading to a decrease in their biological activity or their removal within a short period of time. In addition, peptides typically have low solubility and short circulatory half-lives, limiting their use in therapy. To overcome these limitations, the PEGylation technique has been developed, whereby PEGylated peptides are obtained by covalently linking PEG to peptide molecules. Polyethylene glycol is a polymer with high stability, biocompatibility and low immunogenicity, which is why it is widely used in peptide modification.
Peptide PEGylation Services
BOC Sciences has extensive experience in PEGylation and custom synthesis of peptides to meet our customers' unique needs for peptide PEGylation.
PEG Conjugated Peptide
Peptides can be PEGylated at a variety of different sites. Their N-terminal PEG derivatization can be achieved either by direct PEG acid coupling or by NCL reaction (if the N-terminal is Cys). PEG derivatization of the C-terminus of a peptide is more complicated. One method is achieved by first modifying its C-terminus to a sulfhydryl-substituted acid and then reacting it with a sulfone azide PEG reagent. Another method is achieved by first modifying the C-terminus of the peptide to a hydrazide and then reacting it with an acetonyl PEG reagent. In addition, by embedding non-natural amino acids containing specific functional groups within the peptide chain, the peptide chain can achieve PEGylation at almost any site.
The most common used reagents in the study of PEG modification of peptide compounds is mPEG. First, a carboxyl group, an amino group, or other active group is introduced into the terminal of mPEG, or an amino acid derivative modified by mPEG is prepared, and then they are coupled to the peptide sequence by solid or liquid phase method to realize the PEGylation of N-terminal, C-terminal and some amino acid side chains of the peptide.
PEGylation Method Development
Depending on the needs of the customer's project, BOC Sciences can identify suitable high-quality PEG derivatives and provide the PEGylation samples as well as the complete method development documentation, including custom-developed analytical methods, to support the customer's needs for screening of PEG derivatives as a full range of reagents.
Functional Validation of PEG Conjugated Peptide
a. Stability Assessment
PEGylated peptides typically have enhanced stability, and the effect of PEGylation on peptide stability can be assessed using appropriate conditions (e.g., enzyme digestion, acid-base treatment, thermal stability testing).
b. Bioactivity Analysis
If the target peptide has biological activity, such as antibacterial, antitumor, enzyme activity, the effect of PEGylation on the peptide's biological activity can be evaluated. The appropriate bioactivity analysis methods include cytotoxicity assay, enzyme activity analysis, etc.
Our Advantages
- Deep knowledge and rich experience in PEGylation
- Patented reagents and processes for PEGylation
- Process development and optimization of PEG conjugated peptide production
- Multiple methods for characterization of PEG conjugated peptide
- Quality one-stop service
Project Workflow
Frequently Asked Questions (FAQ)
The PEGylation of peptides typically involves chemical conjugation techniques such as amide bond formation, thiol-reactive coupling, or click chemistry. These methods enable precise attachment of PEG to the peptide's amino acid residues, such as lysine, cysteine, or the N-terminus, ensuring optimal modification for desired properties.
Yes, PEGylated peptides are used in the development of functional coatings for various applications, including medical devices, sensors, and environmental monitoring tools. The PEGylation process enhances the peptide's resistance to biofouling and reduces protein adsorption, making these coatings more durable and effective in diverse environmental conditions.
The degree of PEGylation can be controlled by adjusting reaction conditions such as the concentration of PEG reagent, the reaction time, and the pH level. Additionally, using PEG reagents with different molecular weights or functional groups allows for fine-tuning the conjugation, ensuring that the peptide maintains its activity while gaining the desired solubility and stability.
PEGylation often simplifies the purification process of peptides by increasing their size and altering their charge, making them easier to separate from impurities. Techniques such as size-exclusion chromatography, dialysis, and affinity chromatography can be employed to isolate PEGylated peptides from unreacted reagents or by-products.
