Custom incorporation of non-proteinogenic residues for SAR optimization, stability engineering, and advanced peptide design.
Non-proteinogenic (unnatural) amino acids are residues beyond the 20 canonical amino acids. In peptide design, they enable precise tuning of sterics, polarity, charge, hydrogen bonding, and chemical functionality to meet specific performance goals (e.g., stability, binding, selectivity, permeability).
In practice, unnatural amino acid incorporation is a core strategy for structure–activity relationship (SAR) optimization and stability engineering. Substitutions can improve protease resistance, stabilize or disrupt secondary structure, and introduce functional handles for downstream conjugation or detection.
Related: D-amino acid peptides · N-methyl peptides · Peptide cyclization · Macrocyclic peptides
Reduce enzymatic recognition and improve stability in serum, lysates, or long incubations.
Analog substitutions to map tolerance and tune potency/selectivity at key positions.
Stabilize or disrupt helices/turns using constrained residues and backbone variants.
Selected substitutions can support physicochemical optimization in suitable scaffolds.
Combine non-proteinogenic residues with cyclization strategies for constrained scaffolds.
Introduce clickable/reactive residues for labeling, enrichment, and engagement studies.
Crude to high-purity options (e.g., ≥ 95% / ≥ 98%) depending on sequence and use case.
HPLC/UPLC purity profile plus LC-MS intact mass confirmation (when feasible).
Single-position scans, multi-variant SAR panels, and project-defined libraries.
If you need specific length/scale/QC specs listed on-page, add your exact ranges and we’ll format them to match this template.
Site-specific analog insertion to test tolerance, improve stability, or tune binding at key positions.
Multi-variant panels (single position or multi-position) designed for efficient iteration.
Unnatural residues combined with cyclization, conjugation, or labels (feasibility confirmed during review).
Fluorinated amino acids, N-methylated residues, lipid-like analogs, proprietary building blocks, and project-specific residues can be evaluated upon request. Provide your residue name (or structure), position(s), and intended use.
Analytical HPLC/UPLC purity profile and LC-MS intact mass confirmation (when feasible).
SAR substitution panels, matched controls, and multi-variant sets for iteration.
Additional characterization and custom documentation (project-defined).
Stereochemical L→D substitutions and full D-peptides for protease resistance.
Head-to-tail, side-chain cyclization, disulfide and lactam options.
Backbone tuning to support permeability and stability in select scaffolds.
Azide/alkyne handles and probe-ready peptide designs.
Stable isotope labeling for LC–MS/MS quantification and standards.
PEGylation, lipidation, biotinylation, and other functional conjugates.
Any residue beyond the 20 canonical amino acids, including constrained residues, side-chain analogs, backbone variants, and functional handles.
Often yes. Compatibility depends on residue chemistry and sequence context; feasibility is confirmed during quote review.
Yes. We support single-position and multi-position panels. Share your design intent and constraints so we can propose a practical set.
D-amino acids are stereochemical variants (L→D). Unnatural amino acids are non-proteinogenic residues used to tune stability, conformation, and functionality.
For the fastest quote, send your peptide sequence(s), the substitution(s) and positions (or “recommend”), desired quantity/purity, and intended use (therapeutic discovery, assay standard, probe, etc.). We’ll recommend a practical synthesis route plus purification/QC aligned to your application.
If you’re unsure which residues to use, share the goal (e.g., “increase stability” or “optimize affinity”) and any constraints. We’ll propose practical substitution options and a synthesis + QC plan.
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