What are research peptides?
Peptides sit between single amino acids and full proteins — typically 2 to 50 residues. For a research supplier, a peptide is defined by three properties a certificate can confirm: identity (the correct sequence and mass), purity (the proportion of target peptide versus process-related impurities), and stability (how the material holds up under defined storage). The full primer covers peptide bonds, structure, SPPS, and how each property is measured.
| Property | Peptide | Protein |
|---|---|---|
| Length | 2–50 residues | 50+ residues |
| Structure | Short chains / motifs | Folded three-dimensional |
| Made by | Solid-phase synthesis (SPPS) | Recombinant expression |
| Identity by | ESI-MS + RP-HPLC | MS + chromatography |
Research classes
Beyond the proprietary Lineará Series, individual compounds are grouped by mechanistic research class. The classes describe how a peptide is studied — not any outcome. Each hub covers the class chemistry and lists every member.
Signaling & Neuroactive
Compounds studied in relation to neuropeptide and melanocortin signaling.
Regenerative & Cytoprotective
Compounds studied in the context of tissue repair, cytoprotection, and wound-healing pathways.
Secretagogue & Regulatory
Compounds studied in relation to endocrine signaling and metabolic regulation.
Featured compounds
The most-referenced compounds in the library — each links straight to its full characterization monograph, with the molecular weight from the verified record.
Browse the research
Every compound and every article lives on its own indexable directory — filter, sort, and compare from there. The hub is the doorway.
Compound directory
Every peptide, protein, and reference compound Lineará characterizes, in one A–Z index — filterable by class, type, molecular weight, and certificate.
Compare compounds
Every peptide side by side — molecular weight, chain length, class, and form, with animated metric bars and class filters.
Glossary
Plain, characterization-only definitions for every compound, research class, and analytical method — CAS, HPLC, ESI-MS, lyophilization, RUO, and more.
From the research library
Characterization-first articles, each built from one template and indexed for search.
Data & analytical tools
Concentration & molarity calculator
Compute concentration and molar concentration for laboratory preparation — the analytical prep math behind dissolving a lyophilized peptide in solvent. Characterization arithmetic only; no administration, dosing, or use guidance.
Compare
Structural comparisons across the formulary — molecular weight, chain length, class, and form. Characterization only.
Frequently asked questions
What is the difference between a peptide and a protein?
How is the identity of a peptide determined?
How is peptide purity measured?
What is a certificate of analysis (COA)?
How should lyophilized peptides be stored?
What does “Research Use Only” mean?
References & sources
- Compound identity & physical-property data — public chemical databases (PubChem, ChemSpider). Profiles →
- Solid-phase peptide synthesis — methodology overview. Method notes →
- Reversed-phase HPLC purity determination — analytical standards. Standards →
- Peptide stability & storage — handling literature. Reference index →
- Third-party identity & purity methods — Lineará COA library. COA library →