Custom Peptide Labeling

Fluorescence and dye labeling

Fluorescent and dyes labeled peptides are commonly used in protein binding or localization studies. These labels can be incorporated into fluorescent peptides or labeled peptides at many locations. Usually, they are incorporated into the N-terminal or Cys/Lys side chain. We can construct any feasible fluorescent peptides according to your requirements.

Biotinylated peptides

Biotin is usually attached to the N-terminal or C-terminal, and the N-terminal biotinylation can be carried out directly on the primary amino group, while the biotinylation is usually carried out on the ε-amino group of C-terminal lysine. Creative Peptides routinely synthesizes peptides with the biotin tags.

Peptide tags (Flag\HA\His\Myc)

Tags fused into the target protein can increase the expression level, solubility, folding, purification, and detection of the recombinant protein. The most commonly used small peptide tags are Flag, HA, His, Myc.

Radioactive labeling

Radioactive isotopes, such as 3H (tritium) or 125I (iodine-125), can be incorporated into peptides for various research purposes including receptor binding studies, ligand-receptor interaction assays, and radioimmunoassays.

Phosphorylation labeling

Phosphorylation is a critical post-translational modification that regulates many cellular processes. Peptides can be labeled with phosphate groups (e.g., phospho-tyrosine, phospho-serine, phospho-threonine) to mimic phosphorylated proteins and study signaling pathways or kinase activity.

Acetylation/methylation labeling

Acetylation and methylation are common modifications on lysine and arginine residues, respectively. Peptides can be labeled with acetyl or methyl groups to mimic these modifications and investigate their effects on protein function, localization, and interactions.

Glycosylation labeling

Glycosylation is a common post-translational modification that plays crucial roles in protein folding, stability, and function. Peptides can be labeled with glycans or glycosaminoglycans to study glycoprotein interactions, receptor-ligand binding, and immune responses.

PEGylation

PEG (polyethylene glycol) can be attached to peptides to increase their solubility, stability, and circulating half-life in vivo. Pegylated peptides are used in drug delivery systems, diagnostics, and therapeutic applications.

Metal chelation labeling

Peptides can be labeled with metal chelators such as EDTA or DOTA for chelating metal ions like copper, gadolinium, or technetium. These metal-labeled peptides are employed in molecular imaging, MRI contrast agents, and targeted therapy.

Click chemistry labeling

Click chemistry reactions, like copper-catalyzed azide-alkyne cycloaddition (CuAAC) or strain-promoted azide-alkyne cycloaddition (SPAAC), can be used to label peptides with various functional groups or fluorophores with high specificity and efficiency.