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Peptide Therapy GuideClear peptide education

Understand the source comparison

LL-37 COA: Analytical Method Comparison

HPLC Purity (Area %) Percentage of target peptide vs impurities by chromatographic separation ≥98% by area under curve Confirms synthesis completion and purification efficacy. Values below 95% indicate significant truncated sequences or side products Non-negot

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This page preserves a source comparison for education. It does not add a rating, recommendation or clinical judgment.

  • HPLC Purity (Area %)
  • Percentage of target peptide vs impurities by chromatographic separation
  • ≥98% by area under curve
  • Confirms synthesis completion and purification efficacy. Values below 95% indicate significant truncated sequences or side products
  • Non-negotiable quality threshold; sub-98% material compromises reproducibility
  • Mass Spectrometry (MALDI or ESI)
  • Molecular weight confirmation to verify correct amino acid sequence
  • 4493.3 Da ±0.5 Da
  • Detects amino acid deletions, substitutions, or oxidation. Errors >1 Da indicate structural defects
  • Single most definitive structural verification; variance >0.5 Da = reject batch
  • Endotoxin (LAL Assay)
  • Bacterial lipopolysaccharide contamination from synthesis or handling
  • <1.0 EU/mg (in vitro); <0.1 EU/mg (in vivo)
  • LPS activates TLR4 pathways LL-37 also modulates. Contamination confounds immune response data
  • Critical for immune studies; absence of numeric LAL result = unverifiable quality
  • Peptide Content (Quantitative Amino Acid Analysis)
  • Actual peptide mass per vial vs label claim
  • ≥95% of stated mass
  • Accounts for counterion mass (acetate, TFA) and residual water. Prevents under-dosing in protocols
  • Often omitted by low-grade suppliers; explains why '5mg' vials deliver inconsistent results