Evidence, not personal-use guidance
This page explains research terminology and documentation. It does not provide medical advice, dosing, injection, administration or a recommendation to obtain or use any substance.
What is LL-37?
LL-37 is the 37-residue human cathelicidin-derived peptide studied in innate immunity, membrane interactions and inflammatory biology.
Search results often combine research papers, supplier descriptions and personal claims. Those sources answer different questions. A paper can describe a mechanism or study outcome; only a batch-specific analytical record can describe the tested sample.
Identity and naming
The name reflects the two N-terminal leucines and 37-residue length. Sequence, terminal form, charge state and aggregation behaviour are material to laboratory interpretation.
Useful records state the exact material, expected molecular characteristics, batch code, sample identifier and form. See peptide sequence and molecular weight for why a familiar name is not enough.
What the research base shows
Research spans antimicrobial assays, immunology, wound models and disease associations. Activity can vary greatly with salt, matrix, concentration and assay design, limiting simple cross-study comparisons.
Evidence should be sorted by level: biochemical or cell studies, animal models, observational human data, controlled trials and regulatory evidence. A result at one level should not be silently rewritten as a conclusion at another.
Analytical and COA questions
Identity, purity, aggregation, adsorption and microbial or endotoxin controls may be relevant depending on the experiment. A purity number alone does not make biological assays comparable.
- Does the report name this exact molecular form?
- Does the sample or batch code match the container?
- Are identity, peak-area purity and quantitative content reported separately?
- Can the laboratory and report number be independently traced?
Use the field-by-field COA guide before relying on a headline percentage.
What this page cannot establish
It cannot establish that any commercial material is genuine, sterile, safe, legally supplied or suitable for a particular purpose. Regulatory status and authorised uses can change and vary by country; consult the MHRA Products registry and other relevant official sources.
Frequently asked questions
What kind of peptide is LL-37?
It is a human cathelicidin-derived host-defence peptide.
Why can assay conditions change results?
Ionic strength, matrix, surfaces and aggregation can alter measured peptide activity.
Related external reading:
- independent testing overviewexternal · supplier educational page
External links are editorial references, not endorsements.
Research sources
- PubMed literature search: LL-37.
- ClinicalTrials.gov search: LL-37.
- IUPAC peptide terminology.
- ICH Q2(R2): analytical procedure validation.
Search links are provided because the literature and regulatory status can change. Sources were checked on 19 September 2026.