LL-37 is the only human-derived cathelicidin cationic antimicrobial peptide, CAS 154947?66?7. It is a 37?amino?acid amphipathic α?helical peptide cleaved from precursor protein hCAP-18. Amino?acid sequence: LLGDFFRKSKEKIGKEFKRIVQRIKDFLRNLVPRTES, molecular formula C???H???N??O??, molecular weight 4493.34 g/mol. Supplied as white lyophilized powder with HPLC purity ≥98%.

LL?37 is the only mature cationic cathelicidin peptide generated from human hCAP?18 precursor protein. Rich in positively charged amino?acid residues, this amphipathic molecule can interact with negatively charged membrane structures, making it a widely?studied target within innate immunity research. Unlike most short regulatory peptides, LL?37 features a relatively long full?length sequence, which imposes higher requirements for synthesis fidelity and impurity removal.

Sequence truncations, amino?acid deletion products and partial oxidation are common by?products during manufacturing. Each lot is subjected to mass spectrometry full?scan detection to confirm complete target sequence, while HPLC analysis monitors impurity content. This research material is widely adopted for microbial membrane interaction assays, host?pathogen co?culture models, inflammatory response observation and epithelial cell related mechanism exploration.

Special attention should be paid when preparing working solutions. High?salt environment may interfere with the electrostatic properties of LL?37 and change its experimental performance. The lyophilized form maintains good stability under frozen dark conditions. After reconstitution, do not store aqueous solution for extended periods. Aliquot stock solution for single?use to reduce performance variation brought by repeated freeze?thaw cycles.