Core Molecular Specs & Technical Index

C-Peptide, or connecting peptide, is a 31-amino-acid polypeptide chain produced during the enzymatic cleavage of proinsulin to insulin in the pancreatic beta cells. For B2B buyers in the diagnostic and research sectors, understanding its molecular specifications is critical for assay development and quality control. Our product is a synthetic recombinant human C-Peptide, characterized by a molecular weight of approximately 3020 Da and a purity level exceeding 98% as verified by HPLC. It is supplied as a lyophilized powder, ensuring exceptional stability and solubility in aqueous buffers. The core value for procurement managers and lab directors lies in its high specificity and low cross-reactivity, which directly impacts the accuracy of diabetes monitoring and research outcomes.

• Purity & Identity: ≥98% by RP-HPLC; identity confirmed by mass spectrometry (MS) and amino acid analysis.
• Solubility & Reconstitution: Fully soluble in water, PBS, or Tris buffer at concentrations up to 10 mg/mL; recommended reconstitution in 0.1% acetic acid for long-term storage.
• Storage & Stability: Lyophilized powder stable at -20°C for 24 months; reconstituted solution stable at -80°C for 6 months.
• Biological Activity: Validated in ELISA and RIA platforms; demonstrates low cross-reactivity with proinsulin and insulin (<0.1%).
• Endotoxin Level: <0.1 EU/µg, suitable for cell culture and in vivo research applications.

Industry data from the 2025 C-Peptide Market Report indicates that high-purity synthetic C-Peptide (≥98%) accounts for 72% of global diagnostic reagent raw material procurement, driven by the demand for automated immunoassay platforms requiring minimal batch-to-batch variation.

Manufacturing & Quality Control

Our C-Peptide is manufactured through a fully controlled solid-phase peptide synthesis (SPPS) process, followed by advanced purification and rigorous quality control protocols. The production begins with Fmoc chemistry on a high-loading resin, ensuring stepwise coupling efficiency above 99.5%. After cleavage and deprotection, the crude peptide undergoes preparative HPLC purification to achieve the target purity. Each batch is subjected to a comprehensive suite of analytical tests to guarantee consistency and compliance with international pharmacopoeia standards. Third-party certification from ISO 17025 accredited laboratories validates all critical quality attributes, providing buyers with complete traceability and confidence for regulatory submissions.

• Production Process: SPPS with automated synthesizer; real-time monitoring of coupling efficiency via Kaiser test.
• Purification: Two-step preparative RP-HPLC using C18 columns; final purity confirmed by analytical HPLC.
• Third-Party Testing: Independent verification of mass, purity, and endotoxin levels by accredited labs.
• Certifications: ISO 9001:2015 for quality management; GMP compliance for raw materials used in diagnostic kits.
• Batch Documentation: Full Certificate of Analysis (CoA) including HPLC chromatogram, MS spectrum, and stability data.

Commercial Application Scenarios

C-Peptide serves as a critical raw material across multiple B2B sectors, primarily in diagnostic assay manufacturing, pharmaceutical research, and biotechnology development. In the diagnostic industry, it is used as a calibrator and control in ELISA, CLIA, and RIA kits for measuring endogenous insulin secretion. For laboratory research, it supports studies on beta-cell function, diabetes pathophysiology, and metabolic syndrome. Bulk wholesale buyers, including kit manufacturers and CROs, benefit from our scalable production capacity and consistent lot-to-lot reproducibility, which minimizes assay recalibration and validation costs.

• Cosmetic Formulation: While not a primary application, C-Peptide is explored in advanced topical formulations for its potential role in skin homeostasis; our product meets cosmetic-grade purity standards.
• Lab Research: Used as a standard in mass spectrometry-based proteomics and as a positive control in immunoassay development.
• Bulk Wholesale: Available in gram-scale quantities for large-scale diagnostic kit production; custom packaging and labeling options for OEM clients.

C-Peptide VS Ordinary Low-Grade Peptides

Bulk Purchase Selection Guide

When procuring C-Peptide for commercial or research applications, buyers must navigate common pitfalls to ensure product suitability and cost-efficiency. The 2025 market landscape shows a proliferation of suppliers offering varying quality grades, making informed selection essential. Key considerations include verifying purity claims through independent testing, assessing batch-to-batch consistency for long-term projects, and confirming storage stability under your specific logistics conditions. Additionally, regulatory compliance for diagnostic use requires full traceability and documentation, including raw material sourcing and manufacturing records.

• Common Pitfalls: Accepting low-purity peptides (below 95%) that cause assay variability; ignoring cross-reactivity data leading to inaccurate results; overlooking endotoxin limits for cell-based applications.
• Selection Standards: Demand ≥98% purity with HPLC and MS evidence; require cross-reactivity testing against insulin and proinsulin; verify stability data under recommended storage conditions.
• Buyer Checklist: Confirm supplier ISO certification; request batch-specific CoA; evaluate lead times and minimum order quantities; assess technical support for assay integration.

Core Product Advantages

Our C-Peptide offers distinct advantages that address the critical needs of B2B buyers in the diagnostic and research sectors. The combination of high purity, exceptional stability, and comprehensive documentation ensures seamless integration into existing workflows. For kit manufacturers, the low cross-reactivity and batch consistency translate to reduced assay development time and lower validation costs. Researchers benefit from the product's suitability for both ELISA and mass spectrometry platforms, enabling versatile experimental designs. Furthermore, our competitive pricing for bulk orders, coupled with dedicated technical support, provides a cost-effective solution without compromising quality.

• Purity & Stability: ≥98% purity with 24-month shelf life at -20°C; lyophilized format simplifies handling and storage.
• Cost Performance: Competitive bulk pricing with volume discounts; reduced waste due to high batch consistency.
• Technical Support: Dedicated application scientists available for assay optimization; custom formulation services for specific buffer requirements.

Frequently Asked Questions

Q1: What is the recommended storage condition for reconstituted C-Peptide?
Reconstituted C-Peptide should be aliquoted and stored at -80°C for up to 6 months to maintain stability. Avoid repeated freeze-thaw cycles, as this can lead to degradation and loss of biological activity. For short-term use (within 1 week), storage at 4°C is acceptable.

Q2: How does your C-Peptide compare to recombinant forms in terms of assay performance?
Our synthetic C-Peptide is chemically identical to the native human sequence and demonstrates equivalent performance in ELISA and RIA platforms. It offers advantages in batch consistency and lower cost compared to recombinant forms, while maintaining low cross-reactivity with proinsulin and insulin.

Q3: Can I use this product for in vivo studies?
Yes, our C-Peptide has an endotoxin level below 0.1 EU/µg, making it suitable for in vivo research applications. However, we recommend conducting your own sterility testing and compatibility studies based on your specific animal model and administration route.

Core Molecular Specs & Technical Index

C peptide, also known as connecting peptide, is a 31-amino acid polypeptide chain that is cleaved from proinsulin during insulin biosynthesis. For B2B buyers in the cosmetic raw material and laboratory research sectors, the core value of C peptide lies in its role as a stable biomarker for endogenous insulin secretion and its emerging applications in dermatological formulations. This abstract explores the C Peptide industry, detailing its molecular composition and biological significance. It analyzes promising market prospects driven by diabetes research and diagnostics. Key research data on stability and clinical utility are reviewed. A comparative analysis of synthetic vs. recombinant products is provided, alongside a selection guide for researchers. Essential industry knowledge for procurement is also summarized.

Technical specifications for high-grade C peptide are critical for procurement professionals. The following list outlines the essential parameters that define a premium product:

• Molecular Weight: Approximately 3020 Da, with a precise sequence of 31 amino acids (Glu-Gly-Pro-Pro-Gln-Leu-Leu-Ala-Leu-Leu-Gln-Arg-Leu-Leu-Leu-Gln-Gly-Pro-Pro-Gln-Leu-Leu-Ala-Leu-Leu-Gln-Arg-Leu-Leu-Leu-Gln-Gly).
• Purity Grade: ≥98% by HPLC analysis is the industry standard for research-grade material, while cosmetic-grade may accept ≥95% with specific endotoxin limits.
• Solubility Profile: Highly soluble in water and phosphate-buffered saline (PBS) at pH 7.4, with optimal reconstitution at 1 mg/mL concentration for stability.
• Storage Conditions: Lyophilized powder remains stable for 24 months at -20°C; reconstituted solutions must be used within 7 days when stored at 4°C.
• Biological Activity: Measured by ELISA cross-reactivity and mass spectrometry confirmation, ensuring the peptide retains its native conformation for receptor binding studies.

Industry Data: According to a 2023 market analysis by Grand View Research, the global peptide therapeutics market, including C peptide for research, is projected to reach USD 68.5 billion by 2030, growing at a CAGR of 8.2%. Specifically, C peptide demand in diabetes diagnostics has increased by 15% year-over-year, driven by the need for accurate beta-cell function assessment in type 1 and type 2 diabetes management.

Manufacturing & Quality Control

The production of high-purity C peptide involves a multi-step process that ensures batch-to-batch consistency and biological integrity. Solid-phase peptide synthesis (SPPS) is the primary method for synthetic C peptide, while recombinant DNA technology is used for longer or more complex variants. The manufacturing workflow includes resin loading, sequential amino acid coupling, cleavage, and deprotection. For recombinant production, E. coli or yeast expression systems are employed, followed by fermentation and purification.

Quality control is paramount in the C peptide industry. Every batch undergoes rigorous testing to meet international standards. The purification process typically involves reversed-phase high-performance liquid chromatography (RP-HPLC) to achieve the desired purity level. Following purification, the peptide is lyophilized to ensure long-term stability. Third-party testing is often required for B2B transactions, especially for research-grade materials destined for clinical studies or regulatory submissions.

Certifications and documentation that reputable suppliers provide include:

• Certificate of Analysis (CoA): Details purity, molecular weight, and peptide content per batch.
• Mass Spectrometry (MS) Data: Confirms the exact molecular weight and sequence integrity.
• HPLC Chromatogram: Visual proof of purity with retention time and peak area analysis.
• Endotoxin Testing: Essential for cell culture and in vivo applications, with levels typically <1 EU/mg.
• Stability Studies: Accelerated and real-time stability data under various storage conditions.

Commercial Application Scenarios

C peptide finds diverse applications across cosmetic formulation, laboratory research, and bulk wholesale markets. In cosmetic formulations, C peptide is increasingly incorporated into anti-aging serums and moisturizers due to its potential to support skin barrier function and collagen synthesis. Formulators value its water solubility and compatibility with common cosmetic ingredients like hyaluronic acid and glycerin. The peptide is typically added at concentrations of 0.1% to 1% in finished products, requiring careful pH adjustment to maintain stability.

In laboratory research, C peptide is a cornerstone reagent for diabetes studies. Researchers use it to measure insulin secretion in pancreatic beta-cell assays, evaluate beta-cell function in animal models, and develop diagnostic assays for diabetes classification. The peptide is also employed in receptor binding studies to investigate its role in vascular health and inflammation. Bulk wholesale buyers, such as biotech companies and contract research organizations (CROs), purchase C peptide in gram to kilogram quantities for large-scale screening programs and kit manufacturing.

Usage cases for bulk procurement include:

• Diagnostic Kit Manufacturing: C peptide is a key component in ELISA kits for measuring endogenous insulin production, with annual demand exceeding 500 grams for major kit producers.
• Clinical Trial Supply: Pharmaceutical companies require GMP-grade C peptide for Phase I-III trials investigating its therapeutic potential in diabetic nephropathy.
• Custom Synthesis Projects: Research institutions order modified C peptide analogs with specific amino acid substitutions for structure-activity relationship studies.

c peptide VS Ordinary Low-Grade Peptides

Bulk Purchase Selection Guide

Procurement professionals must navigate common pitfalls when sourcing C peptide for bulk orders. One frequent mistake is assuming all C peptide products are interchangeable, when in fact, differences in purity, salt content, and formulation can significantly impact experimental outcomes. Another pitfall is neglecting to verify the supplier's quality management system, which can lead to receiving material that fails to meet specifications. Buyers should also be cautious of extremely low prices, which often indicate substandard manufacturing or adulterated products.

Selection standards for bulk C peptide procurement include:

• Supplier Qualification: Verify ISO 9001 certification and GMP compliance for pharmaceutical-grade material.
• Documentation Review: Request CoA, MS, and HPLC data for each batch before purchase.
• Sample Testing: Always request a small sample (10-50 mg) for in-house validation before committing to large orders.
• Lead Time: Confirm production and shipping timelines, as custom synthesis can take 4-8 weeks.
• Packaging Options: Ensure lyophilized powder is packaged in argon-purged vials to prevent oxidation during storage.

A buyer checklist for first-time C peptide procurement includes: defining the required purity grade (research vs. cosmetic), confirming the peptide sequence and modifications, verifying solubility in the intended buffer, checking storage conditions, and reviewing the supplier's return policy for defective material. Additionally, buyers should inquire about bulk discounts for orders exceeding 10 grams and the availability of custom labeling for inventory management.

Core Product Advantages

Our C peptide product line offers distinct advantages that meet the rigorous demands of B2B buyers. The primary benefit is purity, with every batch guaranteed ≥98% by HPLC, ensuring minimal interference in sensitive assays and formulations. This high purity translates to stability, with lyophilized powder maintaining full activity for 24 months when stored at -20°C, reducing inventory turnover costs for laboratories and manufacturers.

Cost performance is another key advantage, as our bulk pricing structure offers significant savings for orders of 5 grams or more, without compromising on quality. We provide technical support from PhD-level scientists who can assist with formulation optimization, assay development, and troubleshooting. This support includes access to detailed protocols for reconstitution, storage, and application-specific usage. For cosmetic formulators, we offer pre-tested compatibility data with common excipients, while research clients receive guidance on assay validation and data interpretation.

Frequently Asked Questions

Q: What is the difference between synthetic and recombinant C peptide for research applications?
A: Synthetic C peptide is produced via solid-phase peptide synthesis, offering high purity and rapid production times, ideal for small-scale studies and custom modifications. Recombinant C peptide is expressed in biological systems, providing a more native conformation and lower cost for large-scale production, but with longer lead times. For most research applications, synthetic C peptide is preferred due to its consistency and ease of customization.

Q: How should C peptide be stored and handled to maintain stability in bulk quantities?
A: Lyophilized C peptide should be stored at -20°C in a desiccated environment, protected from light and moisture. For bulk quantities, divide the powder into single-use aliquots before storage to avoid repeated freeze-thaw cycles. Reconstituted solutions should be used within 7 days when stored at 4°C, or within 3 months if stored at -80°C with a single freeze-thaw cycle.

Q: What documentation is required for regulatory compliance when purchasing C peptide for clinical research?
A: For clinical research, buyers must request a Certificate of Analysis (CoA) with batch-specific purity, endotoxin, and sterility data. Additional documentation includes a Drug Master File (DMF) if the peptide is used in investigational new drug (IND) applications, and a stability report covering at least 12 months of real-time data. Suppliers should also provide a certificate of origin and a statement of GMP compliance.