Custom synthesis of linear, cyclic and modified peptides, with flexible purity options and HPLC/MS quality control for research applications.
Alan Scientific provides custom peptide synthesis for academic laboratories, biotechnology companies, and pharmaceutical research teams, including small companies advancing early-stage discovery projects. We support linear, cyclic, and modified peptides for a broad range of research applications.
Peptides are supplied as lyophilized powders with quality control documentation in both printed and electronic formats. Each project is reviewed according to the sequence, modifications, required quantity, purity, and intended use before specifications and delivery timelines are agreed.
Our capabilities include peptides up to 140 amino acids, synthesis scales from µg to kg, and purity options from desalted material to ≥99%. These ranges describe the overall service scope; their availability in combination depends on the sequence and project requirements. Requests involving long or difficult sequences, large quantities, TFA reduction, counterion exchange or endotoxin specifications require project-specific evaluation. Applicable specifications, analytical methods and acceptance criteria are agreed during quotation.

| Specification | Available Options |
|---|---|
| Peptide Types | Linear, cyclic, modified, and specialty peptides |
| Peptide Length | Up to 140 amino acids |
| Synthesis Scale | µg to kg |
| Purity Options | Desalted, ≥75%, ≥80%, ≥85%, ≥90%, ≥95%, ≥98%, ≥99% |
| D-Amino Acids | Partial and all-D peptide synthesis available |
| Non-Natural Amino Acids | Available |
| Peptide Cyclization | Disulfide and head-to-tail cyclization |
| Fluorescent Labeling | Available |
| Biotinylation | Available |
| Protein Conjugation | KLH and BSA conjugation |
| Stable Isotope Labeling | Available |
| Solubility Testing | Available upon request |
| TFA Removal & Counterion Exchange | Reduced TFA (<1% when specified); acetate and hydrochloride (HCl) salt forms available upon request |
| Endotoxin Control | Available; <0.01 EU/µg when specified |
| Quality Control | Analytical HPLC, mass spectrometry, and COA |
| Delivery Form | Lyophilized Powder |
Alan Scientific supports both routine peptide synthesis and projects involving difficult sequences, specialized building blocks, cyclization, labeling, or conjugation.
Custom linear peptides can be synthesized across a broad range of sequence lengths, quantities, and purity specifications for biochemical, cellular, pharmaceutical, and life science research.
Cyclic peptide synthesis is available using strategies including disulfide-bond formation and head-to-tail cyclization. The appropriate cyclization method depends on peptide sequence, reactive-group positioning, and the desired molecular structure.
Peptides up to 140 amino acids can be evaluated for custom synthesis.
Long, hydrophobic, aggregation-prone, or otherwise difficult peptide sequences may require additional synthesis and purification optimization. Sequence feasibility can be reviewed before production.
For background on route selection, read our comparison of direct SPPS and fragment ligation. The appropriate approach remains subject to sequence-specific feasibility review.
Alan Scientific supports incorporation of individual D-amino acids as well as synthesis of peptides composed entirely of D-amino acids.
A broad range of chemical modifications can be incorporated during or after peptide synthesis, depending on sequence design, modification site, and project requirements.
Peptide conjugation to carrier proteins such as KLH and BSA is available for antibody production, immunological studies, and other research applications.
Chemical modification allows synthetic peptides to be adapted for specific biological, analytical, imaging, binding, and drug-discovery applications.
Alan Scientific supports a broad range of peptide modifications and specialty amino acid building blocks.
| Modification Category | Common Options | Typical Applications |
|---|---|---|
| N-Terminal Modifications | Acetylation, formylation, fatty-acid modification and other terminal groups | Stability, charge adjustment, structural studies |
| C-Terminal Modifications | Amidation and other C-terminal modifications | Charge adjustment, peptide stability, native peptide mimicry |
| Fluorescent Labeling | FITC, 5-FAM, Dansyl and other fluorescent dyes | Imaging, cellular uptake, binding assays, localization studies |
| Fluorescent Reporters | MCA, AMC, pNA and related reporter groups | Enzyme assays, protease studies, substrate analysis |
| Fluorophore–Quencher Pairs | Quenched fluorescent peptide designs | Protease assays, enzyme activity studies |
| Biotinylation | N-terminal biotin, side-chain biotin and spacer-assisted biotinylation | Pull-down assays, affinity studies, detection and immobilization |
| Phosphorylation | Phosphoserine, phosphothreonine, phosphotyrosine | Cell signaling, kinase studies, protein interaction research |
| D-Amino Acids | D-Ala, D-Arg, D-Asp, D-Cys, D-Leu and other D-amino acids | Stereochemical studies, stability and peptide optimization |
| All-D Peptides | Peptides composed entirely of D-amino acids | Peptide stability, protease-resistance and research applications |
| Non-Natural Amino Acids | Nle, Nva, Aib, Abu, Ornithine and other specialty residues | Structure–activity studies, peptide optimization |
| N-Methyl Amino Acids | N-methylated amino acid building blocks | Conformational control and peptide optimization |
| Stable Isotope Labeling | Stable isotope-labeled amino acids | Quantitative analysis, MS studies, metabolic and structural research |
| Lipid & Fatty-Acid Modification | Fatty-acid and lipid-related conjugation | Membrane association, peptide delivery and pharmacology research |
| Chelator / Functional Groups | DTPA, HYNIC and related functional groups | Imaging, labeling and specialized research applications |
| Disulfide Cyclization | Intramolecular disulfide-bond formation | Structural stabilization and cyclic peptide studies |
| Head-to-Tail Cyclization | N-to-C terminal cyclization | Conformational restriction and cyclic peptide development |
| KLH Conjugation | Peptide–KLH conjugates | Antibody production and immunization studies |
| BSA Conjugation | Peptide–BSA conjugates | Antibody characterization, assay development and research |
| Multiple Antigenic Peptides (MAPs) | Branched multiple-antigen peptide systems | Immunological studies and antigen presentation |
| Custom Modifications | Project-specific chemical groups and specialty building blocks | Application-dependent peptide research |
Modification feasibility can depend on peptide sequence, modification position, peptide length, purification requirements, and compatibility between functional groups. For specialized projects, modification strategy can be evaluated together with the peptide sequence before synthesis. For guidance on modification sites, labeling options, linkers, and the information needed for a quotation, see our Peptide Modifications service page.
Alan Scientific provides peptide purity specifications ranging from desalted material to ≥99% purity.
Purification requirements depend on the peptide sequence, synthesis complexity, modification, and intended downstream application. More challenging peptides may require additional purification method development to achieve the requested purity and recovery.
For application-specific guidance, see our Recommended Peptide Purity page.
For detailed technical information about RP-HPLC and peptide purification strategy, visit the Peptide Purification & Quality Control Knowledge Center.
| Research Application | What Usually Matters |
|---|---|
| Epitope Mapping | overlapping sequences, library design, purity, plate format |
| Antibody Production | antigen design, terminal accessibility, carrier conjugation |
| Enzyme Substrate Studies | cleavage site, fluorescent/chromogenic reporter, purity |
| PTM Research | modification site, phosphorylation/acetylation/methylation |
| Binding & Interaction Studies | purity, labeling position, biotin/fluorescent tags |
| Functional Studies | sequence, purity, counterion, endotoxin requirements |
Your peptides are delivered as lyophilized powders, accompanied by printed and electronic quality control documentation.
The documentation includes analytical HPLC results, mass spectrometry results, and a Certificate of Analysis (COA). HPLC assesses chromatographic purity, while mass spectrometry supports identity assessment by comparing the observed and expected molecular mass.
Any additional testing and acceptance criteria are agreed during quotation. Please specify requirements such as peptide content determination, residual TFA analysis, or endotoxin testing before the project begins.
Representative analytical data are available on our Peptide Quality Control Report page.
Alan Scientific supports additional peptide services for projects requiring specialized synthesis, purification, or downstream specifications.
Custom peptide library synthesis is available for peptide screening, epitope mapping, alanine scanning, structure–activity studies, target validation, and immunological research.
Available library strategies include overlapping, positional, alanine-scanning, truncated, T-cell, and scrambled peptide libraries.
TFA reduction and exchange to acetate or hydrochloride salts can be evaluated for projects with specific assay or counterion requirements. The appropriate option depends on the peptide sequence, experimental conditions and required analytical specification; exchange is not necessary for every peptide.
Reduced TFA levels (<1% when specified) may be requested, subject to project assessment. The reporting basis, analytical method and acceptance criteria should be agreed during quotation. Routine HPLC purity and mass confirmation do not independently verify residual TFA.
Please include your intended application, working concentration, preferred salt form and any residual-TFA limit with your inquiry.
For help deciding whether to retain the TFA salt, reduce residual TFA or request another counterion, read our guide to peptide TFA removal and acetate versus hydrochloride salt selection.
Controlled-endotoxin peptide preparation is available for projects with specific biological requirements. Endotoxin specifications below 0.01 EU/µg can be requested.
Peptide solubility testing is available upon request, particularly for hydrophobic or modified peptides and projects requiring a defined solvent or peptide concentration.
Additional practical information about peptide handling and reconstitution is available in our Peptide Protocols & Technical Guides.
Alan Scientific peptides have been used in published research across areas including chemical biology, cancer research, immunology, molecular biology, and biomedical research.
These publications provide examples of synthetic peptides used in peptide–protein interaction studies, cellular assays, immunological research, molecular recognition, mechanistic studies, and other experimental applications.
Explore our Publications & Research References for published research involving peptides supplied or synthesized by Alan Scientific.
Our Knowledge Center provides technical information covering peptide synthesis, purification, modifications, building blocks, handling, and experimental applications.
Peptide Purification & Quality Control
Peptide Modifications & Applications
Amino Acids & Peptide Building Blocks
Peptide Protocols & Technical Guides
For common questions about peptide synthesis, purity, conjugation, D-amino acids, solubility, storage, purification, and SPPS, visit our Peptide Synthesis Q&A.
To request a quotation, send us:
Your peptide sequence, including terminal groups and modification sites
Required quantity per peptide and target purity
Intended research application
Any preferred salt form or additional testing requirements
Your requested delivery date
Our U.S.-based sales team can assist with project inquiries, while our U.S. warehousing operations support product supply. If you are unsure about a specification, describe your experimental needs so the requirements can be reviewed before synthesis.
For projects that also require sequence design or optimization, AI-guided peptide design and synthesis support is available as an additional service.
Request a Peptide Quote or email [email protected]