Peptide Conjugation Service: Click Chemistry

Peptide Conjugation by Click Chemistry and Site-Specific Ligation

Click Chemistry CuAAC reactions

DBCO azide click chemistry

LifeTein provides peptide conjugation services for projects that require selective, efficient linkage between peptides and other functional components such as PEGs, oligonucleotides, lipids, fluorophores, small-molecule payloads, nanoparticles, or proteins. Depending on the project, we use maleimide–thiol ligation, azide–alkyne click chemistry, copper-free SPAAC, tetrazine–TCO chemistry, and related site-selective strategies.

In practice, the most appropriate chemistry depends on the molecule pair, the desired site of attachment, the stability requirements, and whether the conjugation must occur under copper-free or highly orthogonal conditions. For many routine peptide conjugations, maleimide–thiol chemistry remains the simplest and most direct method when a defined cysteine is available. Click chemistry becomes especially useful when orthogonality, multifunctional assembly, or oligonucleotide compatibility is important.

Conjugation Strategy Overview

Maleimide–thiol	Often the most straightforward route for cysteine-containing peptides and PEG-, lipid-, or payload-bearing maleimide reagents
CuAAC	Useful for azide–alkyne ligation in well-controlled synthetic settings
SPAAC	Copper-free azide–cyclooctyne ligation for sensitive systems and bioorthogonal workflows
Tetrazine–TCO	Fast bioorthogonal ligation suitable for specialized dual-functional or in situ labeling concepts
Project types	PEGylation, oligonucleotide conjugation, peptide drug conjugates, peptide-lipid conjugates, and multifunctional research constructs

How We Position the Different Conjugation Routes

Maleimide–thiol chemistry is often the preferred first option when a single cysteine attachment point is available and a PEG, lipid, or payload maleimide reagent is suitable.
Click chemistry is especially useful when orthogonality matters, when the partner molecule is an oligonucleotide or complex scaffold, or when multifunctional assembly is required.
SPAAC and tetrazine–TCO are particularly useful for copper-free or highly bioorthogonal workflows.

Conjugation Services Supported by This Platform

Peptide PEGylation Service: Site-selective PEGylation using maleimide or click-compatible routes, including larger PEGs such as PEG2000 and PEG4000.
Peptide–Oligonucleotide Conjugates: DNA–peptide, RNA–peptide, PMO–peptide, PNA–peptide, and related conjugates.
Peptide Drug Conjugation: Peptide–payload and linker–payload conjugation strategies for targeted drug research.
Peptide–Lipid and LNP-Related Conjugation: Peptide-functionalized lipids, PEG-lipids, and related nanoparticle-facing chemistries.

Peptide conjugates for screening

Representative Applications

Peptide–PEG conjugates for improved pharmacokinetic or formulation behavior
Peptide–oligonucleotide conjugates for delivery, uptake, and intracellular targeting studies
Peptide–drug conjugates for targeted therapeutic research
Peptide-functionalized lipids or PEG-lipids for LNP and nanomedicine studies
Multifunctional constructs containing a peptide, a payload, and a reporter or click handle

Which chemistry is right for your project?

If you already know your preferred chemistry, we can work from that. If not, we can usually help decide whether a cysteine–maleimide route, PEG-linker route, SPAAC, CuAAC, or tetrazine–TCO strategy is the better fit for your construct.

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