Custom Synthesis
Modified and Specialized Peptides
Common Modifications
N-Terminal Modifications
| Modification | Application |
| Acetylation (Ac-) | Increases stability, mimics natural N-terminus |
| Myristoylation | Membrane targeting |
| PEGylation | Prolonged half-life |
| Biotinylation | Affinity purification, detection |
| Fluorescent labels | Imaging, tracking |
C-Terminal Modifications
| Modification | Application |
| Amidation (-NH₂) | Most common, mimics natural peptides |
| Esterification | Prodrug strategies |
| C-terminal tags | Purification handles |
Side-Chain Modifications
- Phosphorylation (Ser, Thr, Tyr)
- Glycosylation
- Palmitoylation
- Statine analogs (protease inhibitors)
Specialty Peptide Types
Cyclic Peptides
- Head-to-tail cyclization
- Side-chain to side-chain
- Disulfide-constrained
D-Amino Acid Substitution
- Enhanced metabolic stability
- Often retains activity
Peptidomimetics
- Non-natural backbone modifications
- Improved bioavailability
Isotope Labeling
| Label | Application |
| ¹⁵N | NMR studies |
| ¹³C | Metabolic tracing |
| ²H (deuterium) | MS quantification |
Synthesis Considerations for Modified Peptides
| Modification | Challenge | Recommendation |
| Phosphorylation | Acid-labile (may cleave during TFA) | Use protected building blocks, careful cleavage |
| PEGylation | Large conjugate, heterogeneity | Purify post-modification |
| Cyclization | Dimerization risk | High dilution conditions |
| Label incorporation | Cost of specialty building blocks | Minimum excess, validated coupling |
- Modified and Specialized Peptides — Review the section above for key parameters, methods, and quality criteria.
- Common Modifications — Review the section above for key parameters, methods, and quality criteria.
- Specialty Peptide Types — Review the section above for key parameters, methods, and quality criteria.
- Isotope Labeling — See the section for detailed parameters and specifications.
Key Takeaways
- Modified and Specialized Peptides — Review the section above for key parameters, methods, and quality criteria.
- Common Modifications — Review the section above for key parameters, methods, and quality criteria.
- Specialty Peptide Types — Review the section above for key parameters, methods, and quality criteria.
- Isotope Labeling — See the section above for detailed parameters and specifications.
🔗 Related: SPPS Process | Peptide Folding | Fmoc Amino Acids | Custom Peptide Synthesis & OEM