LL-37 Peptide in Felm — Antimicrobial Research Guide
LL-37 research guide for Felm. Human cathelicidin antimicrobial peptide — covers immune modulation, purity testing, COA verification, and sourcing guidance.
For anyone in Felm searching for LL-37, the first thing to know is that this compound is available only through an online research supply market. The benefit of this online-only market is that serious vendors are judged entirely by their analytical documentation, giving researchers better verification tools than any physical store could provide. The primary quality indicators for LL-37 are HPLC purity ≥98%, molecular identity verified through mass spectrometry, and a bacterial endotoxin panel — all documented in a lot-traced Certificate of Analysis. The sections below cover what Felm researchers need to know about purchasing, testing, and working with LL-37 for scientific research use.
Understanding LL-37 — Biology & Evidence
The melanocortin receptor family (MC1R through MC5R) mediates a diverse range of physiological functions, and research peptides like Melanotan-2 and PT-141 (Bremelanotide) act on different receptor subtypes with different research applications. MT-2 has broad melanocortin receptor activity and has been studied for pigmentation (MC1R), appetite suppression (MC4R), and other endpoints. PT-141 is a more specific MC3R/MC4R agonist studied primarily for CNS-mediated effects. For researchers in Felm designing experiments with LL-37, the specific receptor binding profile determines which outcomes are mechanistically attributable to the compound and which require additional explanation.
How to Source LL-37 — Vendor Guide
Quality LL-37 sourcing begins with a useful first test: does this vendor publish batch-specific COAs proactively? Vendors who do are demonstrating research-grade standards. When reviewing a LL-37 COA, verify: the batch number traces to your order, HPLC purity is ≥98%, mass spec establishes identity, and endotoxin levels are within acceptable research limits. The combination of peer feedback and direct document verification is the most reliable sourcing approach — community feedback surfaces recurring issues no single purchase reveals, and vice versa. Bacteriostatic water is the correct reconstitution medium for LL-37 — it contains 0.9% benzyl alcohol that prevents microbial contamination and extends reconstituted shelf life to 30 days refrigerated.
Order LL-37 — ships to Felm
COA-verified · International tracking · Research grade
As a research compound, LL-37 has not completed the clinical trial process required for pharmaceutical approval — its safety profile is characterised by preclinical data and restricted human research data. Reconstitute LL-37 with bacteriostatic water at a concentration matched to your dosing requirements; a standard 5mg reconstituted in 2mL produces 2.5mg/mL — or 25mcg per insulin syringe unit. Endotoxin testing in the LL-37 COA is absolutely required — gram-negative bacterial endotoxins can trigger severe inflammatory responses at trace quantities, and no cost saving makes omitting this acceptable. Researchers running multi-compound protocols with LL-37 should examine published studies for potential interaction data before beginning combination research.
Frequently Asked Questions
How long can reconstituted peptide be stored?
Reconstituted peptide in bacteriostatic water should be stored refrigerated at 2-8°C and used within 30 days. Some peptides have shorter stability windows once reconstituted. For longer storage, freeze aliquots of reconstituted peptide at −20°C, though repeated freeze-thaw cycles should be avoided.
How do I reconstitute a lyophilized peptide?
Add bacteriostatic water slowly to the vial, directing it against the side wall rather than directly onto the lyophilized cake. Use a standard concentration appropriate for your dosing (e.g., 2mL bac water per 5mg vial = 2.5mg/mL). Gently swirl — never shake — to dissolve. Store reconstituted peptide at 2-8°C.
What is bacteriostatic water and why is it used?
Bacteriostatic water is sterile water containing 0.9% benzyl alcohol as a preservative. It inhibits bacterial growth in the vial, allowing multi-use over 30 days when kept refrigerated. It is the standard reconstitution medium for research peptides. Do not use tap water, saline, or plain sterile water for multi-use reconstitution.
Are research peptides legal?
Research peptides are generally legal to purchase and possess for research purposes in most countries. They are not approved pharmaceuticals, not scheduled controlled substances (in most jurisdictions), and importable for legitimate research use. Regulatory status varies by country and evolves over time — verify current status in your jurisdiction.
What is a Certificate of Analysis (COA) for research peptides?
A COA is a quality document from a third-party analytical laboratory showing the results of testing for a specific product batch. For research peptides, it should include HPLC purity, mass spectrometry identity confirmation, bacterial endotoxin levels, and a residual solvent panel. The batch number should match your specific vial.