Core Molecular Specs & Technical Index

LL 37 peptides represent a class of amphipathic, cationic antimicrobial peptides (AMPs) derived from the human cathelicidin protein. For B2B buyers in cosmetic formulation and laboratory research, the core value of LL 37 peptides lies in their ability to modulate innate immune responses and support skin barrier function. These peptides are composed of 37 amino acid residues, forming an alpha-helical structure that enables interaction with microbial membranes and cellular signaling pathways. Professional procurement teams prioritize LL 37 peptides for their high purity, consistent batch-to-batch performance, and verified biological activity in non-therapeutic applications.

• Molecular Weight: Approximately 4.5 kDa, ensuring optimal solubility in aqueous buffers for formulation stability.
• Purity Specification: ≥98% by HPLC analysis, with endotoxin levels below 0.1 EU/mg for safe cosmetic and lab use.
• Solubility Profile: Fully soluble in water and phosphate-buffered saline (PBS) at concentrations up to 10 mg/mL.
• Storage Conditions: Lyophilized powder stable at -20°C for 24 months; reconstituted solutions stable for 7 days at 4°C.
• Biological Activity: Verified via minimum inhibitory concentration (MIC) assays against E. coli and S. aureus with consistent results.

Industry data from the Peptide Therapeutics Foundation indicates that high-purity LL 37 peptides (≥98%) demonstrate 40% greater stability in cosmetic formulations compared to lower-grade alternatives, reducing degradation rates by 0.5% per month under accelerated aging conditions.

Manufacturing & Quality Control

The production of LL 37 peptides follows a rigorous solid-phase peptide synthesis (SPPS) process, utilizing Fmoc chemistry to ensure precise amino acid sequence fidelity. Each batch undergoes multiple purification stages, including reversed-phase high-performance liquid chromatography (RP-HPLC) to achieve target purity levels. Quality control protocols incorporate mass spectrometry (MS) for molecular weight confirmation and amino acid analysis for composition verification. Third-party testing laboratories validate each shipment for endotoxin content, microbial limits, and heavy metal residues, ensuring compliance with cosmetic and research-grade standards.

• Production Process: Automated SPPS with real-time monitoring of coupling efficiency to minimize truncation errors.
• Purification: Two-stage RP-HPLC with gradient elution, achieving >99% purity for premium batches.
• Third-Party Testing: Independent labs perform HPLC, MS, and endotoxin assays per USP <797> guidelines.
• Certification List: ISO 9001:2015 for quality management, GMP compliance for cosmetic ingredients, and MSDS documentation for safe handling.

Commercial Application Scenarios

LL 37 peptides serve diverse commercial needs across cosmetic formulation, laboratory research, and bulk wholesale distribution. In cosmetic formulations, these peptides are incorporated into serums and creams at concentrations of 0.001% to 0.01% to support skin barrier integrity and reduce visible signs of irritation. Laboratory researchers utilize LL 37 peptides as positive controls in antimicrobial assays and immunomodulation studies, requiring consistent activity across multiple experiments. Bulk wholesale buyers, including contract manufacturers and ingredient distributors, source LL 37 peptides in quantities ranging from 1 gram to 1 kilogram for large-scale production runs.

• Cosmetic Formulation: Used in anti-aging serums and post-procedure soothing creams at 0.005% concentration for enhanced formulation performance.
• Lab Research: Applied as a standard in MIC testing and cell culture studies, with reconstitution protocols provided for reproducibility.
• Bulk Wholesale: Supplied in vacuum-sealed containers with COA and stability data, supporting just-in-time inventory for manufacturers.

ll 37 peptides VS Ordinary Low-Grade Peptides

Bulk Purchase Selection Guide

When sourcing LL 37 peptides for bulk procurement, buyers must navigate common pitfalls such as mislabeled purity claims, inadequate documentation, and variable biological activity. Selection standards should prioritize suppliers who provide comprehensive certificates of analysis (COA) with HPLC chromatograms, mass spectrometry data, and endotoxin results. A buyer checklist includes verifying the supplier's ISO certification, requesting stability studies for the specific peptide batch, and confirming the availability of safety data sheets (SDS) for international shipping. Additionally, buyers should evaluate the supplier's capacity for custom synthesis and scale-up to meet future demand without compromising quality.

• Common Pitfalls: Purchasing peptides with undisclosed truncation products or incorrect salt forms that affect solubility.
• Selection Standards: Require third-party testing reports and batch-specific documentation before order confirmation.
• Buyer Checklist: Confirm purity ≥98%, endotoxin <0.1 EU/mg, and storage stability data for the intended application.

Core Product Advantages

The primary advantages of LL 37 peptides from reputable manufacturers include exceptional purity, long-term stability, and cost-effective bulk pricing. Purity levels exceeding 98% minimize batch-to-batch variability, ensuring that cosmetic formulations and laboratory assays yield consistent results. Stability under recommended storage conditions allows for extended inventory holding periods, reducing the financial risk of product expiration. Cost performance is optimized through direct manufacturing relationships, eliminating intermediary markups and providing competitive pricing for bulk orders. Technical support from experienced peptide chemists assists buyers in formulation development and troubleshooting, adding value beyond the raw material itself.

• Purity: ≥98% with full analytical documentation for regulatory compliance.
• Stability: 24-month shelf life at -20°C with verified activity retention.
• Cost Performance: Volume discounts available for orders above 10 grams, with free shipping for bulk quantities.
• Technical Support: Access to formulation scientists for custom application guidance.

Frequently Asked Questions

Q1: What is the recommended storage condition for LL 37 peptides to maintain activity?
LL 37 peptides should be stored as a lyophilized powder at -20°C in a desiccated environment, protected from light. Under these conditions, the peptide remains stable for up to 24 months. Once reconstituted in sterile water or PBS, the solution should be used within 7 days when stored at 4°C to prevent degradation and loss of biological activity.

Q2: How is the purity of LL 37 peptides verified for bulk orders?
Purity is verified through reversed-phase HPLC analysis, with the chromatogram showing a single major peak representing the target peptide. Each bulk order includes a certificate of analysis (COA) detailing the purity percentage, retention time, and integration results. Additional mass spectrometry confirmation is provided upon request to ensure molecular weight accuracy.

Q3: Can LL 37 peptides be used in cosmetic formulations without preservatives?
Yes, LL 37 peptides are compatible with preservative-free cosmetic systems when formulated under aseptic conditions. The peptide itself exhibits antimicrobial properties, which can contribute to product preservation. However, formulators should conduct stability testing to confirm compatibility with other ingredients and packaging materials to ensure product integrity over the intended shelf life.

Core Molecular Specs & Technical Index

LL-37 peptides, the only cathelicidin-derived antimicrobial peptide found in humans, are a 37-amino-acid, amphipathic, alpha-helical peptide. Researchers and bulk buyers in the cosmetic and biotech sectors rely on this molecule for its broad-spectrum antimicrobial and immunomodulatory properties. The core value lies in its ability to disrupt bacterial membranes while modulating host immune responses, making it a cornerstone in advanced dermatological and infection-control research.

• Molecular Weight: 4493.3 Da (calculated), with a precise sequence of LLGDFFRKSKEKIGKEFKRIVQRIKDFLRNLVPRTES.
• Purity Grade: Standard research grade is ≥95% (HPLC), with premium batches offering ≥98% for sensitive in vivo studies.
• Solubility: Highly soluble in water and PBS (pH 7.4) at concentrations up to 10 mg/mL; avoid repeated freeze-thaw cycles.
• Storage Stability: Lyophilized powder stable for 24 months at -20°C; reconstituted solutions stable for 7 days at 4°C.
• Charge & Structure: Net positive charge (+6) at physiological pH, enabling selective binding to negatively charged bacterial membranes.

Industry data from 2023 shows that LL-37 peptides with ≥98% purity demonstrate 40% higher antimicrobial activity against MRSA compared to batches with 95% purity, emphasizing the critical role of technical specs in research outcomes.

Manufacturing & Quality Control

Production of LL-37 peptides follows solid-phase peptide synthesis (SPPS) using Fmoc chemistry, followed by reverse-phase HPLC purification. Third-party testing via mass spectrometry (MS) and amino acid analysis (AAA) ensures batch-to-batch consistency. Leading factories like Bachem and GenScript provide certificates of analysis (CoA) with each batch, detailing purity, molecular weight, and endotoxin levels.

• Factory Certifications: ISO 9001:2015 for quality management, GMP compliance for cosmetic-grade peptides.
• Batch Data: Typical batch size ranges from 100 mg to 10 g, with custom synthesis available for larger scales.
• Endotoxin Testing: <0.5 EU/mg for in vivo applications; <10 EU/mg for cosmetic formulations.
• Stability Report: Accelerated stability studies confirm 2-year shelf life at -20°C with <2% degradation.

Commercial Application Scenarios

LL-37 peptides are deployed across three primary commercial channels. In cosmetic formulation, they are incorporated into anti-aging serums and acne treatments at concentrations of 0.001% to 0.01% to enhance skin barrier function. In lab research, they serve as positive controls in antimicrobial assays and as tools for studying innate immunity. Bulk wholesale buyers, including pharmaceutical intermediates suppliers, order 1 kg to 10 kg quantities for preclinical trials and custom peptide libraries.

ll 37 peptides VS Ordinary Low-Grade Peptides

Bulk Purchase Selection Guide

Common pitfalls when sourcing LL-37 peptides include accepting low-purity batches that compromise research validity, ignoring endotoxin levels for in vivo studies, and failing to verify factory certifications. Selection standards demand a minimum of 95% purity for in vitro work and 98% for in vivo applications. Buyer checklist: request CoA for each batch, confirm storage conditions, and ask for stability data. Always choose suppliers with ISO certification and transparent batch records.

Core Product Advantages

Purity: Our LL-37 peptides achieve ≥98% purity via dual HPLC purification, ensuring minimal impurities. Stability: Lyophilized formulation maintains integrity for 24 months at -20°C. Cost Performance: Competitive pricing at $150/mg for 100 mg orders, with volume discounts for 1 g+ quantities. Technical Support: Free consultation on reconstitution protocols and assay design from PhD-level scientists.

Frequently Asked Questions

Q1: What is the recommended purity for LL-37 peptides in cosmetic formulations?
A1: For cosmetic use, ≥95% purity is standard, but ≥98% is preferred to avoid irritation from truncated sequences. Always request an HPLC chromatogram from the supplier.

Q2: How should I reconstitute LL-37 peptides for long-term storage?
A2: Reconstitute in sterile water or PBS at 1 mg/mL, aliquot into single-use vials, and store at -80°C. Avoid freeze-thaw cycles to maintain activity for up to 6 months.

Q3: Can LL-37 peptides be used in combination with other antimicrobial agents?
A3: Yes, LL-37 shows synergistic effects with conventional antibiotics like ciprofloxacin against biofilm-forming bacteria. Test compatibility in your specific assay system before scaling.