LL-37 Peptide in Junction — Antimicrobial Research Guide
LL-37 research guide for Junction. Human cathelicidin antimicrobial peptide — covers immune modulation, purity testing, COA verification, and sourcing guidance.
LL-37 isn't stocked on pharmacy shelves in Junction or virtually any local market — it's a research-grade peptide distributed through a dedicated online market. This matters because LL-37 quality ranges widely across the market — from verified research-grade material to products with serious contamination — and the vendor is the entire quality system. Vendors worth sourcing from openly share batch-matched Certificates of Analysis showing HPLC purity data, mass spec identity confirmation, endotoxin levels, and residual solvent results — all for the exact batch you are purchasing. The sections below cover what Junction researchers need to know about sourcing, verifying, and handling LL-37 for research purposes.
LL-37: What the Research Shows
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 Junction designing experiments with LL-37, the specific receptor binding profile determines which outcomes are mechanistically attributable to the compound and which require additional explanation.
LL-37 Purchasing Guide
Quality LL-37 sourcing begins with a straightforward question: does this vendor make batch-matched COAs available before purchase? Suppliers that publish proactively are signalling genuine quality commitment. When reviewing a LL-37 COA, verify: the batch number corresponds to your vial, HPLC purity is ≥98%, mass spec establishes identity, and endotoxin levels are at acceptable levels for the intended application. Community reputation in research forums is a valuable complement to COA verification — vendors with sustained positive community feedback have earned that standing through repeat quality delivery. Store lyophilised LL-37 at −20°C until ready to use; reconstitute only the amount needed for the near-term protocol and store the rest at −20°C.
Order LL-37 — ships to Junction
COA-verified · International tracking · Research grade
LL-37 is sold for research purposes only and is not approved for human use by the FDA or equivalent regulatory bodies — all information here is for educational purposes only. Storage requirements for LL-37: lyophilised powder at minus 20°C, reconstituted solution stored refrigerated at 2-8°C and used within 30 days; reconstitute only with sterile bacteriostatic water. Verify the endotoxin level in your LL-37 batch COA before use in any in-vivo protocol — look for results reported in endotoxin units per mg or mL and confirm they fall within appropriate thresholds. Researchers running multi-compound protocols with LL-37 should review the available literature for documented interactions before running stacked compound experiments.
Frequently Asked Questions
What purity should research peptides be?
Research-grade peptides should be ≥98% pure as confirmed by HPLC chromatography. Some vendors offer 99%+ purity for applications requiring higher specification material. Purity below 95% is generally considered inadequate for reliable research use.
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.
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.
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.
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.
